Title: | Thermodynamic Calculations and Diagrams for Geochemistry |
---|---|
Description: | An integrated set of tools for thermodynamic calculations in aqueous geochemistry and geobiochemistry. Functions are provided for writing balanced reactions to form species from user-selected basis species and for calculating the standard molal properties of species and reactions, including the standard Gibbs energy and equilibrium constant. Calculations of the non-equilibrium chemical affinity and equilibrium chemical activity of species can be portrayed on diagrams as a function of temperature, pressure, or activity of basis species; in two dimensions, this gives a maximum affinity or predominance diagram. The diagrams have formatted chemical formulas and axis labels, and water stability limits can be added to Eh-pH, oxygen fugacity- temperature, and other diagrams with a redox variable. The package has been developed to handle common calculations in aqueous geochemistry, such as solubility due to complexation of metal ions, mineral buffers of redox or pH, and changing the basis species across a diagram ("mosaic diagrams"). CHNOSZ also implements a group additivity algorithm for the standard thermodynamic properties of proteins. |
Authors: | Jeffrey Dick [aut, cre] (0000-0002-0687-5890) |
Maintainer: | Jeffrey Dick <[email protected]> |
License: | GPL-3 |
Version: | 2.1.0-18 |
Built: | 2024-10-05 05:58:36 UTC |
Source: | https://github.com/r-forge/chnosz |
CHNOSZ is a package for thermodynamic calculations, primarily with applications in geochemistry and compositional biology. It can be used to calculate the standard molal thermodynamic properties and chemical affinities of reactions relevant to geobiochemical processes, and to visualize the equilibrium activities of species on chemical speciation and predominance diagrams.
To view the manual, run help.start()
then select ‘Packages’ and ‘CHNOSZ’. Examples in the function help pages can be run by pasting the code block into the R console.
Also check out the vignette anintro (An Introduction to CHNOSZ).
Run the command examples()
to run all of the examples provided in CHNOSZ. This should take about a minute.
Each help page (other than this one) has been given one of the following “concept index entries”:
Main workflow: info
, subcrt
, basis
, species
, affinity
, equilibrate
, diagram
Extended workflow: swap.basis
, buffer
, mosaic
, EOSregress
Thermodynamic calculations: util.formula
, makeup
, util.units
, Berman
, nonideal
, util.misc
Water properties: water
, util.water
, DEW
, IAPWS95
Protein properties: protein.info
, add.protein
, util.protein
, util.seq
, ionize.aa
Utility functions: util.expression
, util.plot
, util.array
, util.list
, palply
These concept entries are visible to help.search
(aka ??
).
For example, help pages related to thermodynamic data can be listed using ??"thermodynamic data"
.
All thermodynamic data and examples are provided on an as-is basis.
It is up to you to check not only the accuracy of the data, but also the suitability of the data AND computational techniques for your problem.
By combining data taken from different sources, it is possible to build an inconsistent and/or nonsensical calculation.
An attempt has been made to provide a default database (OBIGT) that is internally consistent, but no guarantee can be made.
If there is any doubt about the accuracy or suitability of data for a particular problem, please consult the primary sources (see thermo.refs
).
This package would not exist without the scientific influence and friendship of the late Professor Harold C. Helgeson. The ‘src/H2O92D.f’ file with Fortran code for calculating the thermodynamic and electrostatic properties of H2O is modified from the SUPCRT92 package (Johnson et al., 1992).
Work on CHNOSZ at U.C. Berkeley from ca. 2003 to 2008 was supported in part by research grants to HCH from the U.S. National Science Foundation and Department of Energy. In 2009–2011, development of this package was partially supported by NSF grant EAR-0847616 to JMD.
Johnson, J. W., Oelkers, E. H. and Helgeson, H. C. (1992) SUPCRT92: A software package for calculating the standard molal thermodynamic properties of minerals, gases, aqueous species, and reactions from 1 to 5000 bar and 0 to 1000°C. Comp. Geosci. 18, 899–947. doi:10.1016/0098-3004(92)90029-Q
Add or modify species in the thermodynamic database.
add.OBIGT(file, species = NULL, force = TRUE) mod.OBIGT(..., zap = FALSE)
add.OBIGT(file, species = NULL, force = TRUE) mod.OBIGT(..., zap = FALSE)
file |
character, path to a file |
species |
character, names of species to load from file |
force |
logical, force replacement of already existing species? |
... |
character or numeric, properties of species to modify in the thermodynamic database |
zap |
logical, clear preexisting parameters? |
Note: change made to OBIGT are lost if you reload the database by calling reset
or OBIGT
or if you quit the R session without saving it.
add.OBIGT
is used to update the thermodynamic database (thermo$OBIGT
) in the running session.
The format (column names) of the specified file must be the same as the extdata/OBIGT/*.csv
files provided with CHNOSZ.
Note that this includes both the E_units
and model
columns, which were added in versions 1.3.3 and 2.0.0.
file
is first matched against the names of files in the extdata/OBIGT
directory packaged with CHNOSZ.
In this case, the file suffixes are removed, so ‘DEW’, ‘organic_aq’, and ‘organic_cr’ are valid names.
If there are no matches to a system file, then file
is interpreted as the path a user-supplied file.
If species
is NULL (default), all species listed in the file are used.
If species
is given and matches the name(s) of species in the file, only those species are added to the database.
By default, species in the file replace any existing species having the same combination of name and state.
Set force
to FALSE to avoid replacing species that are present in (thermo()$OBIGT
).
When adding (not replacing) species, there is no attempt made to keep the order of physical states in the database (aq-cr-liq-gas); the function simply adds new rows to the end of thermo
$OBIGT.
As a result, retrieving the properties of an added aqueous species using info
requires an explicit state="aq"
argument to that function if a species with the same name is present in one of the cr, liq or gas states.
mod.OBIGT
changes one or more of the properties of species or adds species to the thermodynamic database.
The name of the species to add or change must be supplied as the first argument of ...
or as a named argument (named ‘name’).
Additional arguments to mod.OBIGT
refer to the name of the property(s) to be updated and are matched to any part of compound column names in thermo()$OBIGT
.
For instance, either ‘z’ or ‘T’ matches the ‘z.T’ column.
The values provided should also include order-of-magnitude scaling of HKF and DEW model parameters (see thermo
).
When adding new species, a chemical formula should be included along with the values of any of the thermodynamic properties.
The formula is taken from the ‘formula’ argument, or if that is missing, is taken to be the same as the ‘name’ of the species.
An error occurs if the formula is not valid (i.e. can not be parsed by makeup
).
For new species, properties that are not specified become NA, except for ‘state’ and ‘E_units’, which take default values from thermo()$opt
.
These defaults can be overridden by giving a value for ‘state’ or ‘E_units’ in the arguments.
‘model’, if missing, is set to ‘HKF’ for state == "aq"
or ‘CGL’ otherwise.
When modifying some existing minerals in OBIGT, model = "CGL"
should be explicitly given in order to override the Berman model.
When modifying species, the parameters indicated by the named arguments of mod.OBIGT
are updated.
Use zap = TRUE
to replace all prexisting parameters (except for state
and model
) with NA values.
The values returned (invisible
-y) are the indices of the added and/or modified species.
Apps, J. and Spycher, N. (2004) Data qualification for thermodynamic data used to support THC calculations. DOC.20041118.0004 ANL-NBS-HS-000043 REV 00. Bechtel SAIC Company, LLC.
Bazarkina, E. F., Zotov, A. V., and Akinfiev, N. N. (2010) Pressure-dependent stability of cadmium chloride complexes: Potentiometric measurements at 1-1000 bar and 25°C. Geology of Ore Deposits 52, 167–178. doi:10.1134/S1075701510020054
Kitadai, N. (2014) Thermodynamic prediction of glycine polymerization as a function of temperature and pH consistent with experimentally obtained results. J. Mol. Evol. 78, 171–187. doi:10.1007/s00239-014-9616-1
Shock, E. L., Helgeson, H. C. and Sverjensky, D. A. (1989) Calculation of the thermodynamic and transport properties of aqueous species at high pressures and temperatures: Standard partial molal properties of inorganic neutral species. Geochim. Cosmochim. Acta 53, 2157–2183. doi:10.1016/0016-7037(89)90341-4
Stefánsson, A. (2001) Dissolution of primary minerals of basalt in natural waters. I. Calculation of mineral solubilities from 0°C to 350°C. Chem. Geol. 172, 225–250. doi:10.1016/S0009-2541(00)00263-1
Sverjensky, D. A., Shock, E. L., and Helgeson, H. C. (1997) Prediction of the thermodynamic properties of aqueous metal complexes to 1000 °C and 5 kbar. Geochim. Cosmochim. Acta 61, 1359–1412. doi:10.1016/S0016-7037(97)00009-4
thermo
(description of OBIGT), mod.buffer
(modify buffer definitions), logB.to.OBIGT
(fit thermodynamic parameters to formation constants)
## Modify an existing species (not real properties) ialanine <- mod.OBIGT("alanine", state = "cr", G = 0, H = 0, S = 0) # We have made the values of G, H, and S inconsistent # with the elemental composition of alanine, so the following # now produces a message about that info(ialanine) ## Add an aqueous species (default) with Gibbs energy given in J/mol ## (the same as the default) and today's date date <- as.character(Sys.Date()) iCl2O <- mod.OBIGT("Cl2O", date = date, E_units = "J", G = 87738) info(iCl2O) ## Add a solid species with a name that is different from the formula mod.OBIGT("lorem-ipsum", formula = "C123", state = "cr", G = -12345678) # Retrieve the data for this species using either name or formula info(info("lorem-ipsum")) info(info("C123")) # Reset database OBIGT() ## Using add.OBIGT(): # Compare stepwise stability constants of cadmium chloride complexes # using data from Sverjensky et al., 1997 and Bazarkina et al., 2010 Cdspecies <- c("Cd+2", "CdCl+", "CdCl2", "CdCl3-", "CdCl4-2") P <- c(1, seq(25, 1000, 25)) SSH97 <- lapply(1:4, function(i) { subcrt(c(Cdspecies[i], "Cl-", Cdspecies[i+1]), c(-1, -1, 1), T=25, P=P)$out$logK }) file <- system.file("extdata/adds/BZA10.csv", package="CHNOSZ") add.OBIGT(file) BZA10 <- lapply(1:4, function(i) { subcrt(c(Cdspecies[i], "Cl-", Cdspecies[i+1]), c(-1, -1, 1), T=25, P=P)$out$logK }) matplot(P, do.call(cbind, SSH97), type="l") matplot(P, do.call(cbind, BZA10), type="l", add=TRUE, lwd=2) legend("topleft", legend=c("", "", "Sverjensky et al., 1997", "Bazarkina et al., 2010"), lwd=c(0, 0, 1, 2), bty="n") # Make reaction labels y <- c(1.8, 0.2, -0.5, -1) invisible(lapply(1:4, function(i) { text(800, y[i], describe.reaction(subcrt(c(Cdspecies[i], "Cl-", Cdspecies[i+1]), c(-1, -1, 1), T=25, P=1)$reaction)) })) # Restore default database OBIGT() # Another use of add.OBIGT() # Compare Delta G of AABB = UPBB + H2O # (Figure 9 of Kitadai, 2014) # Default database has values from Kitadai, 2014 Kit14 <- subcrt(c("[AABB]", "[UPBB]", "H2O"), c(-1, 1, 1), T = seq(0, 300, 10)) # Load superseded parameters for [UPBB] from Dick et al., 2006 mod.OBIGT("[UPBB]", G = -21436, H = -45220, S = 1.62) DLH06 <- subcrt(c("[AABB]", "[UPBB]", "H2O"), c(-1, 1, 1), T = seq(0, 300, 10)) xlab <- axis.label("T"); ylab <- axis.label("DG", prefix="k") plot(Kit14$out$T, Kit14$out$G/1000, type = "l", ylim = c(10, 35), xlab = xlab, ylab = ylab) lines(DLH06$out$T, DLH06$out$G/1000, lty = 2) legend("topleft", c("Dick et al., 2006", "Kitadai, 2014"), lty = c(2, 1)) title(main = "AABB = UPBB + H2O; after Figure 9 of Kitadai, 2014") # Restore default database OBIGT() # Another use of add.OBIGT(): calculate Delta G of # H4SiO4 = SiO2 + 2H2O using various sources of data for SiO2. # First, get H4SiO4 from Stefansson, 2001 add.OBIGT("AS04", "H4SiO4") T <- seq(0, 350, 10) s1 <- subcrt(c("H4SiO4", "SiO2", "H2O"), c(-1, 1, 2), T = T) # Now, get SiO2 from Apps and Spycher, 2004 add.OBIGT("AS04", "SiO2") s2 <- subcrt(c("H4SiO4", "SiO2", "H2O"), c(-1, 1, 2), T = T) # Plot logK from the first and second calculations plot(T, s1$out$G, type = "l", xlab = axis.label("T"), ylab = axis.label("DG"), ylim = c(-500, 2500)) lines(T, s2$out$G, lty = 2) # Add title and legend title(main = describe.reaction(s1$reaction)) stxt <- lapply(c("H4SiO4", "SiO2", "SiO2"), expr.species) legend("top", c("Shock et al., 1989", "Apps and Spycher, 2004"), title = as.expression(expr.species("SiO2")), lty = c(1, 2)) legend("topright", "Stef\u00e1nsson, 2001", title = as.expression(expr.species("H4SiO4"))) abline(h = 0, lty = 3, col = 8) # Take-home message: SiO2 from Ste01 is compatible with H4SiO4 from Ste01 # at low T, but SiO2 from Shock et al., 1989 (the default in OBIGT) isn't OBIGT()
## Modify an existing species (not real properties) ialanine <- mod.OBIGT("alanine", state = "cr", G = 0, H = 0, S = 0) # We have made the values of G, H, and S inconsistent # with the elemental composition of alanine, so the following # now produces a message about that info(ialanine) ## Add an aqueous species (default) with Gibbs energy given in J/mol ## (the same as the default) and today's date date <- as.character(Sys.Date()) iCl2O <- mod.OBIGT("Cl2O", date = date, E_units = "J", G = 87738) info(iCl2O) ## Add a solid species with a name that is different from the formula mod.OBIGT("lorem-ipsum", formula = "C123", state = "cr", G = -12345678) # Retrieve the data for this species using either name or formula info(info("lorem-ipsum")) info(info("C123")) # Reset database OBIGT() ## Using add.OBIGT(): # Compare stepwise stability constants of cadmium chloride complexes # using data from Sverjensky et al., 1997 and Bazarkina et al., 2010 Cdspecies <- c("Cd+2", "CdCl+", "CdCl2", "CdCl3-", "CdCl4-2") P <- c(1, seq(25, 1000, 25)) SSH97 <- lapply(1:4, function(i) { subcrt(c(Cdspecies[i], "Cl-", Cdspecies[i+1]), c(-1, -1, 1), T=25, P=P)$out$logK }) file <- system.file("extdata/adds/BZA10.csv", package="CHNOSZ") add.OBIGT(file) BZA10 <- lapply(1:4, function(i) { subcrt(c(Cdspecies[i], "Cl-", Cdspecies[i+1]), c(-1, -1, 1), T=25, P=P)$out$logK }) matplot(P, do.call(cbind, SSH97), type="l") matplot(P, do.call(cbind, BZA10), type="l", add=TRUE, lwd=2) legend("topleft", legend=c("", "", "Sverjensky et al., 1997", "Bazarkina et al., 2010"), lwd=c(0, 0, 1, 2), bty="n") # Make reaction labels y <- c(1.8, 0.2, -0.5, -1) invisible(lapply(1:4, function(i) { text(800, y[i], describe.reaction(subcrt(c(Cdspecies[i], "Cl-", Cdspecies[i+1]), c(-1, -1, 1), T=25, P=1)$reaction)) })) # Restore default database OBIGT() # Another use of add.OBIGT() # Compare Delta G of AABB = UPBB + H2O # (Figure 9 of Kitadai, 2014) # Default database has values from Kitadai, 2014 Kit14 <- subcrt(c("[AABB]", "[UPBB]", "H2O"), c(-1, 1, 1), T = seq(0, 300, 10)) # Load superseded parameters for [UPBB] from Dick et al., 2006 mod.OBIGT("[UPBB]", G = -21436, H = -45220, S = 1.62) DLH06 <- subcrt(c("[AABB]", "[UPBB]", "H2O"), c(-1, 1, 1), T = seq(0, 300, 10)) xlab <- axis.label("T"); ylab <- axis.label("DG", prefix="k") plot(Kit14$out$T, Kit14$out$G/1000, type = "l", ylim = c(10, 35), xlab = xlab, ylab = ylab) lines(DLH06$out$T, DLH06$out$G/1000, lty = 2) legend("topleft", c("Dick et al., 2006", "Kitadai, 2014"), lty = c(2, 1)) title(main = "AABB = UPBB + H2O; after Figure 9 of Kitadai, 2014") # Restore default database OBIGT() # Another use of add.OBIGT(): calculate Delta G of # H4SiO4 = SiO2 + 2H2O using various sources of data for SiO2. # First, get H4SiO4 from Stefansson, 2001 add.OBIGT("AS04", "H4SiO4") T <- seq(0, 350, 10) s1 <- subcrt(c("H4SiO4", "SiO2", "H2O"), c(-1, 1, 2), T = T) # Now, get SiO2 from Apps and Spycher, 2004 add.OBIGT("AS04", "SiO2") s2 <- subcrt(c("H4SiO4", "SiO2", "H2O"), c(-1, 1, 2), T = T) # Plot logK from the first and second calculations plot(T, s1$out$G, type = "l", xlab = axis.label("T"), ylab = axis.label("DG"), ylim = c(-500, 2500)) lines(T, s2$out$G, lty = 2) # Add title and legend title(main = describe.reaction(s1$reaction)) stxt <- lapply(c("H4SiO4", "SiO2", "SiO2"), expr.species) legend("top", c("Shock et al., 1989", "Apps and Spycher, 2004"), title = as.expression(expr.species("SiO2")), lty = c(1, 2)) legend("topright", "Stef\u00e1nsson, 2001", title = as.expression(expr.species("H4SiO4"))) abline(h = 0, lty = 3, col = 8) # Take-home message: SiO2 from Ste01 is compatible with H4SiO4 from Ste01 # at low T, but SiO2 from Shock et al., 1989 (the default in OBIGT) isn't OBIGT()
Functions to get amino acid compositions and add them to protein list for use by other functions.
add.protein(aa, as.residue = FALSE)
add.protein(aa, as.residue = FALSE)
aa |
data frame, amino acid composition in the format of |
as.residue |
logical, normalize by protein length? |
A ‘protein’ in CHNOSZ is defined by its identifying information and the amino acid composition, stored in thermo$protein
.
The names of proteins in CHNOSZ are distinguished from those of other chemical species by having an underscore character ("_") that separates two identifiers, referred to as the protein
and organism
.
An example is ‘LYSC_CHICK’.
The purpose of the functions described here is to identify proteins and work with their amino acid compositions.
From the amino acid compositions, the thermodynamic properties of the proteins can be estimated by group additivity.
Given a data frame of amino acid compositions in the format of thermo()$protein
, add.protein
adds them to thermo()$protein
for use by other functions in CHNOSZ.
The amino acid compositions of proteins in aa
with the same name as one in thermo()$protein
are replaced.
Set as.residue
to TRUE to normalize by protein length; each input amino acid composition is divided by the corresponding number of residues, with the result that the sum of amino acid frequencies for each protein is 1.
For add.protein
, the rownumbers of thermo()$protein
that are added and/or replaced.
read_fasta
for reading amino acid compositions from FASTA files.
pinfo
for protein-level functions (length, chemical formulas, reaction coefficients of basis species).
# Read a file with the amino acid compositions of several poliovirus protein subunits file <- system.file("extdata/protein/POLG.csv", package = "CHNOSZ") aa <- read.csv(file) # Add the proteins to CHNOSZ iprotein <- add.protein(aa) # Calculate length and elemental formula protein.length(iprotein) protein.formula(iprotein)
# Read a file with the amino acid compositions of several poliovirus protein subunits file <- system.file("extdata/protein/POLG.csv", package = "CHNOSZ") aa <- read.csv(file) # Add the proteins to CHNOSZ iprotein <- add.protein(aa) # Calculate length and elemental formula protein.length(iprotein) protein.formula(iprotein)
Calculate the chemical affinities of formation reactions of species.
affinity(..., property = NULL, sout = NULL, exceed.Ttr = FALSE, exceed.rhomin = FALSE, return.buffer = FALSE, return.sout = FALSE, balance = "PBB", iprotein = NULL, loga.protein = 0, transect = NULL)
affinity(..., property = NULL, sout = NULL, exceed.Ttr = FALSE, exceed.rhomin = FALSE, return.buffer = FALSE, return.sout = FALSE, balance = "PBB", iprotein = NULL, loga.protein = 0, transect = NULL)
... |
numeric, zero or more named arguments, used to identify the variables of interest in the calculations. For argument recall, pass the output from a previous calculation of |
property |
character, the property to be calculated. Default is ‘A’, for chemical affinity of formation reactions of species of interest |
sout |
list, output from |
exceed.Ttr |
logical, allow |
exceed.rhomin |
logical, allow |
return.buffer |
logical. If |
return.sout |
logical, return only the values calculated with |
balance |
character. This argument is used to identify a conserved basis species (or ‘PBB’) in a chemical activity buffer. Default is ‘PBB’. |
iprotein |
numeric, indices of proteins in |
loga.protein |
numeric, logarithms of activities of proteins identified in |
transect |
logical, force a transect calculation, even for three or fewer values of the variables? |
affinity
calculates the chemical affinities of reactions to form the species of interest from the basis species.
The equation used to calculate chemical affinity (A), written for base-10 (decimal) logarithms, is =
, where
is the equilibrium constant of the reaction,
is the activity product of the species in the reaction, and 2.303 is the conversion factor from natural to decimal logarithms.
The calculation of chemical affinities relies on the current definitions of the
basis
species and species
of interest.
Calculations are possible at single values of temperature, pressure, ionic strength and chemical activities of the basis species, or as a function of one or more of these variables.
The argument property
can be changed to calculate other thermodynamic properties of formation reactions.
Valid properties are ‘A’ or NULL for chemical affinity, ‘logK’ or ‘logQ’ for logarithm of equilibrium constant and reaction activity product, or any of the properties available in subcrt
except for ‘rho’.
The properties returned are those of the formation reactions of the species of interest from the basis species.
It is also possible to calculate the properties of the species of interest themselves (not their formation reactions) by setting the property
to ‘G.species’, ‘Cp.species’, etc.
Except for ‘A’, the properties of proteins or their reactions calculated in this manner are restricted to nonionized proteins.
Zero, one, or more leading arguments to the function identify which of the chemical activities of basis species, temperature, pressure and/or ionic strength to vary.
The names of each of these arguments may be the formula of any of the basis species of the system, or ‘T’, ‘P’, ‘pe’, ‘pH’, ‘Eh’, or ‘IS’ (but names may not be repeated).
The names of charged basis species such as ‘K+’ and ‘SO4-2’ should be quoted when used as arguments.
The value of each argument is of the form c(min, max)
or c(min, max, res)
where min
and max
refer to the minimimum and maximum values of variable identified by the name of the argument, and res
is the resolution, or number of points along which to do the calculations; res
is assigned a default value of 256 if it is missing.
For any arguments that refer to basis species, the numerical values are the logarithms of activity (or fugacity for gases) of that basis species.
If ‘T’, ‘P’, and/or ‘IS’ are not among the var
s, their constant values can be supplied in T
, P
, or IS
(in mol kg).
The units of ‘T’ and ‘P’ are those set by
T.units
and P.units
(on program start-up these are °C and bar, respectively).
sout
, if provided, replaces the call to subcrt
, which can greatly speed up the calculations if this intermediate result is stored by other functions.
exceed.Ttr
is passed to subcrt
so that the properties of mineral phases beyond their transition temperatures can optionally be calculated.
If one or more buffers are assigned to the definition of basis
species, the logarithms of activities of these basis species are taken from the buffer (see buffer
).
The iprotein
and loga.protein
arguments can be used to compute the chemical affinities of formation reactions of proteins that are not in the current species
definition.
iprotein
contains the indices (rownumbers) of desired proteins in thermo$protein
.
This uses some optimizations to calculate the properties of many proteins in a fraction of the time it would take to calculate them individually.
When the length(s) of the variables is(are) greater than 3, the function enters the ‘transect’ mode of operation.
In this mode of operation, instead of performing the calculations on an -dimensional grid, the affinities are calculated on a transect of changing T, P, and/or chemical activity of basis species.
Argument recall is invoked by passing a previous result of affinity
as the first argument.
The function then calls itself using the settings from the previous calculation, with additions or modifications indicated by the remaining arguments in the current function call.
A list, elements of which are fun
the name of the function (‘affinity’), args
all of the arguments except for ‘sout’ (these are used for argument recall), sout
output from subcrt
, property
name of the calculated property (‘A’ for chemical affinity), basis
and species
definition of basis species and species of interest in effect at runtime, T
and P
temperature and pressure, in the system units of Kelvin and bar, set to numeric()
(length=0) if either one is a variable, vars
the names of the variables, vals
the values of the variables (a list, one element for each variable), values
the result of the calculation (a list, one element for each species, with names taken from the species index in thermo$OBIGT
).
The elements of the lists in vals
and values
are arrays of dimensions, where
is the number of variables.
The values of chemical affinity of formation reactions of the species are returned in dimensionless units (for use with decimal logarithms, i.e., A/
).
Names other than ‘T’ or ‘P’ in vars
generally refer to basis species, and the corresponding vals
are the logarithms of activity or fugacity.
However, if one or more of pe
, Eh
or pH
is among the variables of interest, vals
holds the values of the those variables as indicated.
Helgeson, H. C., Richard, L, McKenzie, W. F., Norton, D. L. and Schmitt, A. (2009) A chemical and thermodynamic model of oil generation in hydrocarbon source rocks. Geochim. Cosmochim. Acta 73, 594–695. doi:10.1016/j.gca.2008.03.004
ionize.aa
, activated if proteins are among the species of interest, ‘H+’ is in the basis and thermo()$opt$ionize.aa
is TRUE.
equilibrate
for using the results of affinity
to calculate equilibrium activities of species, and diagram
to plot the results.
demo("saturation")
for an example using the argument recall feature.
## Set up a system and calculate ## chemical affinities of formation reactions basis(c("SiO2", "MgO", "H2O", "O2"), c(-5, -5, 0, 999)) species(c("quartz","enstatite","forsterite")) # Chemical affinities (A/2.303RT) at 25 deg C and 1 bar affinity() # At higher temperature and pressure affinity(T = 500, P = 2000) # At 25 temperatures and pressures, # some are in the low-density region so we suppress warnings suppressWarnings(affinity(T = c(500, 1000, 5), P = c(1000, 5000, 5))) # Equilibrium constants of formation reactions affinity(property = "logK") # Standard molal Gibbs energies of species, # in units set by E.units() (default: J/mol) affinity(property = "G.species") # Standard molal Gibbs energies of reactions affinity(property = "G") # A T,P-transect # (fluid pressure from Helgeson et al., 2009 Fig. 7) affinity(T = c(25, 110, 115, 215), P = c(11, 335, 500, 1450))
## Set up a system and calculate ## chemical affinities of formation reactions basis(c("SiO2", "MgO", "H2O", "O2"), c(-5, -5, 0, 999)) species(c("quartz","enstatite","forsterite")) # Chemical affinities (A/2.303RT) at 25 deg C and 1 bar affinity() # At higher temperature and pressure affinity(T = 500, P = 2000) # At 25 temperatures and pressures, # some are in the low-density region so we suppress warnings suppressWarnings(affinity(T = c(500, 1000, 5), P = c(1000, 5000, 5))) # Equilibrium constants of formation reactions affinity(property = "logK") # Standard molal Gibbs energies of species, # in units set by E.units() (default: J/mol) affinity(property = "G.species") # Standard molal Gibbs energies of reactions affinity(property = "G") # A T,P-transect # (fluid pressure from Helgeson et al., 2009 Fig. 7) affinity(T = c(25, 110, 115, 215), P = c(11, 335, 500, 1450))
Define the basis species of a chemical system.
basis(species = NULL, state = NULL, logact = NULL, delete = FALSE, add = FALSE)
basis(species = NULL, state = NULL, logact = NULL, delete = FALSE, add = FALSE)
species |
character, names or formulas of species, or numeric, indices of species |
state |
character, physical states or names of buffers |
logact |
numeric, logarithms of activities or fugacities |
delete |
logical, delete the current basis definition? |
add |
logical, add species to the current basis definition? |
The basis species represent the possible range of chemical compositions for all the species of interest. As used here, a set of basis species is valid only if it satisifes two conditions: 1) the number of basis species is the same as the number of chemical elements (including charge) in those species and 2) the square matrix representing the elemental stoichiometries of the basis species has a real inverse.
To create a basis definition, call basis
with the names or formulas of the basis species in the species
argument, or all numeric values as species indices (rownumbers in thermo()$OBIGT
).
The special names ‘pH’, ‘pe’ and ‘Eh’ can also be used; they get translated into the names of the proton (‘H+’) and electron (‘e-’) as appropriate.
If desired, include the state
for the named species and the logarithms of activity (fugacity for gases) in logact
.
The latter defaults to zero (unit activity) if not specified.
To modify an existing basis definition, the physical states or logarithms of activities of species can be changed by calling basis
with a species
argument that has the formulas (not names) or indices of species in the existing basis.
If either of the second or third arguments to basis
is of type character, it refers to the physical state (if present in thermo()$OBIGT$state
) or a chemical activity buffer
(if present in thermo()$buffers$name
).
If either of these arguments is numeric it specifies the logarithms of activities (or fugacities for gases) of the basis species.
In case ‘pH’, ‘pe’ or ‘Eh’ is named, the logarithm of activity of the basis species is converted from these values.
For example, a value of 7 for pH is stored as a logarithm of activity of -7.
If add
is TRUE, then the function attempts to add the indicated species
to the basis definition.
This only works if the enlarged set of species is a valid basis set as described above.
If the formed species
are currently defined, their formation reactions are modified accordingly (with zeroes for the newly added basis species).
If add
is FALSE, and if basis
is called with NULL values of both state
and logact
, the new set of species, if they are a valid basis set, completely replaces any existing basis definition.
When this occurs, any existing species definition (created by the species
function) is deleted.
Call basis
with delete
set to TRUE or species
set to ‘""’ to clear the basis definition and that of the species
, if present.
If the value of basis
is one of the keywords in the following table, the corresponding set of basis species is loaded, and their activities are given preset values.
The basis species identified by these keywords are aqueous except for H2O (liq), O2 (gas) and Fe2O3 (hematite).
CHNOS |
CO2, H2O, NH3, H2S, O2 |
CHNOS+ |
CO2, H2O, NH3, H2S, O2, H+ |
CHNOSe |
CO2, H2O, NH3, H2S, e-, H+ |
CHNOPS+ |
CO2, H2O, NH3, H3PO4, H2S, O2, H+ |
CHNOPSe |
CO2, H2O, NH3, H3PO4, H2S, e-, H+ |
MgCHNOPS+ |
Mg+2, CO2, H2O, NH3, H3PO4, H2S, O2, H+ |
MgCHNOPSe |
Mg+2, CO2, H2O, NH3, H3PO4, H2S, e-, H+ |
FeCHNOS |
Fe2O3, CO2, H2O, NH3, H2S, O2 |
FeCHNOS+ |
Fe2O3, CO2, H2O, NH3, H2S, O2, H+ |
QEC4 |
cysteine, glutamic acid, glutamine, H2O, O2 |
QEC |
cysteine, glutamic acid, glutamine, H2O, O2 |
QEC+ |
cysteine, glutamic acid, glutamine, H2O, O2, H+ |
QCa |
glutamine, cysteine, acetic acid, H2O, O2 |
QCa+ |
glutamine, cysteine, acetic acid, H2O, O2, H+ |
The logarithms of activities of amino acids in the ‘QEC4’ basis are -4 (i.e., basis II in Dick, 2016); those in ‘QEC’ and ‘QEC+’ are set to approximate concentrations in human plasma (see Dick, 2017).
Returns the value of thermo()$basis
after any modifications; or, if delete
is TRUE, its value before deletion (invisibly).
Dick, J. M. (2016) Proteomic indicators of oxidation and hydration state in colorectal cancer. PeerJ 4:e2238. doi:10.7717/peerj.2238
Dick, J. M. (2017) Chemical composition and the potential for proteomic transformation in cancer, hypoxia, and hyperosmotic stress. PeerJ 5:e3421 doi:10.7717/peerj.3421
info
to query the thermodynamic database in order to find what species are available.
makeup
is used by basis
to generate the stoichiometric matrix from chemical formulas.
swap.basis
is used to change the chemical compounds (species formulas) used in the basis definition while keeping the chemical potentials of the elements unaltered.
species
for setting up the formation reactions from basis species.
## Define basis species # with one, two or three elements basis("O2") basis(c("H2O", "O2")) basis(c("H2O", "O2", "H+")) ## Clear the basis species basis("") ## Not run: ## Marked dontrun because they produce errors # Fewer species than elements basis(c("H2O", "H+")) # More species than elements basis(c("H2O", "O2", "H2", "H+")) # Non-independent species basis(c("CO2", "H2O", "HCl", "Cl-", "H+")) ## End(Not run) ## Specify activities and states basis(c("H2O", "O2", "CO2"), c(-2, -78, -3), c("liq", "aq", "aq")) # Change logarithms of activities/fugacities basis(c("H2O", "O2"), c(0, -80)) # Change state of CO2 basis("CO2", "gas")
## Define basis species # with one, two or three elements basis("O2") basis(c("H2O", "O2")) basis(c("H2O", "O2", "H+")) ## Clear the basis species basis("") ## Not run: ## Marked dontrun because they produce errors # Fewer species than elements basis(c("H2O", "H+")) # More species than elements basis(c("H2O", "O2", "H2", "H+")) # Non-independent species basis(c("CO2", "H2O", "HCl", "Cl-", "H+")) ## End(Not run) ## Specify activities and states basis(c("H2O", "O2", "CO2"), c(-2, -78, -3), c("liq", "aq", "aq")) # Change logarithms of activities/fugacities basis(c("H2O", "O2"), c(0, -80)) # Change state of CO2 basis("CO2", "gas")
Calculate thermodynamic properties of minerals using the equations of Berman (1988).
Berman(name, T = 298.15, P = 1, check.G = FALSE, calc.transition = TRUE, calc.disorder = TRUE)
Berman(name, T = 298.15, P = 1, check.G = FALSE, calc.transition = TRUE, calc.disorder = TRUE)
name |
character, name of mineral |
T |
numeric, temperature(s) at which to calculate properties (K) |
P |
numeric, pressure(s) at which to calculate properties (bar) |
check.G |
logical, check consistency of G, H, and S? |
calc.transition |
logical, include calculation of polymorphic transition properties? |
calc.disorder |
logical, include calculation of disordering properties? |
This function calculates the thermodynamic properties of minerals at high P and T using equations given by Berman (1988).
These minerals should be listed in thermo()$OBIGT
with the state ‘cr’ and chemical formula, and optionally an abbreviation and references, but all other properties set to NA.
The standard state thermodynamic properties and parameters for the calculations are stored in data files under extdata/Berman
, or can be read from a user-created file specified by thermo()$opt$Berman
.
The equation used for heat capacity is CP = k0 + k1*T-0.5 + k2*T-2 + k3*T-3 + k4*T-1 + k5*T + k6*T2.
This is an extended form Eq. 4 of Berman (1988) as used in the winTWQ program (Berman, 2007).
The equation used for volume is V(P, T) / V(1 bar, 298.15 K) = 1 + v1 * (T - 298.15) + v2 * (T - 298.15)2 + v3 * (P - 1) + v4 * (P - 1)2 (Berman, 1988, Eq. 5, with terms reordered to follow winTWQ format).
The equations used for lambda transitions follow Eqs. 8-14 of Berman (1988).
The equation used for the disorder contribution between Tmin and Tmax is CP[dis] = d0 + d1*T-0.5 + d2*T-2 + d3*T + d4*T2 (Berman, 1988, Eq. 15).
The parameters correspond to Tables 2 (GfPrTr
, HfPrTr
, SPrTr
, VPrTr
), 3a (k0
to k3
), 4 (v1
to v4
), 3b (transition parameters: Tlambda
to dTH
), and 5 (disorder parameters: Tmax
, Tmin
, d1
to d4
and Vad
) of Berman (1988).
Following the winTWQ data format, multipliers are applied to the volume parameters only (see below).
Note that VPrTr
is tabulated in J bar-1 mol-1, which is equal to 10 cm3 mol-1.
A value for GfPrTr
is not required and is only used for optional checks (see below).
Numeric values (possibly 0) should be assigned for all of HfPrTr
, SPrTr
, VPrTr
, k0
to k6
and v1
to v4
.
Missing (or NA) values are permitted for the transition and disorder parameters, for minerals where they are not used.
The data files have the following 30 columns:
name |
mineral name (must match an entry with a formula but NA properties in thermo()$OBIGT ) |
GfPrTr |
standard Gibbs energy at 298.15 K and 1 bar (J mol-1) (Benson-Helgeson convention) |
HfPrTr |
standard enthalpy at 298.15 K and 1 bar (J mol-1) |
SPrTr |
standard entropy at 298.15 K and 1 bar (J mol-1 K-1) |
VPrTr |
standard volume at 298.15 K and 1 bar (J bar-1) [1 J bar-1 = 10 cm3] |
k0 ... k6 |
k0 (J mol-1 K-1) to k6 |
v1 |
v1 (K-1) * 105 |
v2 |
v2 (K-2) * 105 |
v3 |
v3 (bar-1) * 105 |
v4 |
v4 (bar-2) * 108 |
Tlambda |
Tλ (K) |
Tref |
Tref (K) |
dTdP |
dT / dP (K bar-1) |
l1 |
l1 ((J/mol)0.5 K-1) |
l2 |
l2 ((J/mol)0.5 K-2) |
DtH |
ΔTtH (J mol-1) |
Tmax |
temperature at which phase is fully disordered (TD in Berman, 1988) (K) |
Tmin |
reference temperature for onset of disordering (t in Berman, 1988) (K) |
d0 ... d4 |
d0 (J mol-1 K-1) to d4 |
Vad |
constant that scales the disordering enthalpy to volume of disorder (d5 in Berman, 1988) |
The function outputs apparent Gibbs energies according to the Benson-Helgeson convention (ΔG = ΔH - TΔS) using the entropies of the elements in the chemical formula of the mineral to calculate ΔS (cf. Anderson, 2005).
If check.G
is TRUE, the tabulated value of GfTrPr
(Benson-Helgeson) is compared with that calculated from HfPrTr
- 298.15*DSPrTr
(DSPrTr
is the difference between the entropies of the elements in the formula and SPrTr
in the table).
A warning is produced if the absolute value of the difference between tabulated and calculated GfTrPr
is greater than 1000 J/mol.
If the function is called with missing name
, the parameters for all available minerals are returned.
A data frame with T
(K), P
(bar), G
, H
, S
, and Cp
(energetic units in Joules), and V
(cm3 mol-1).
Anderson, G. M. (2005) Thermodynamics of Natural Systems, 2nd ed., Cambridge University Press, 648 p. https://www.worldcat.org/oclc/474880901
Berman, R. G. (1988) Internally-consistent thermodynamic data for minerals in the system Na2O-K2O-CaO-MgO-FeO-Fe2O3-Al2O3-SiO2-TiO2-H2O-CO2. J. Petrol. 29, 445-522. doi:10.1093/petrology/29.2.445
Berman, R. G. and Aranovich, L. Ya. (1996) Optimized standard state and solution properties of minerals. I. Model calibration for olivine, orthopyroxene, cordierite, garnet, and ilmenite in the system FeO-MgO-CaO-Al2O3-TiO2-SiO2. Contrib. Mineral. Petrol. 126, 1-24. doi:10.1007/s004100050233
Berman, R. G. (2007) winTWQ (version 2.3): A software package for performing internally-consistent thermobarometric calculations. Open File 5462, Geological Survey of Canada, 41 p. doi:10.4095/223425
Helgeson, H. C., Delany, J. M., Nesbitt, H. W. and Bird, D. K. (1978) Summary and critique of the thermodynamic properties of rock-forming minerals. Am. J. Sci. 278-A, 1–229. https://www.worldcat.org/oclc/13594862
# Other than the formula, the parameters aren't stored in # thermo()$OBIGT, so this shows NAs info(info("quartz", "cr")) # Properties of alpha-quartz (aQz) at 298.15 K and 1 bar Berman("quartz") # Gibbs energies of aQz and coesite at higher T and P T <- seq(200, 1300, 100) P <- seq(22870, 31900, length.out = length(T)) G_aQz <- Berman("quartz", T = T, P = P)$G G_Cs <- Berman("coesite", T = T, P = P)$G # That is close to the univariant curve (Ber88 Fig. 4), # so the difference in G is close to 0 DGrxn <- G_Cs - G_aQz all(abs(DGrxn) < 100) # TRUE # Make a P-T diagram for SiO2 minerals (Ber88 Fig. 4) basis(c("SiO2", "O2"), c("cr", "gas")) species(c("quartz", "quartz,beta", "coesite"), "cr") a <- affinity(T = c(200, 1700, 200), P = c(0, 50000, 200)) diagram(a) ## Getting data from a user-supplied file ## Ol-Opx exchange equilibrium, after Berman and Aranovich, 1996 species <- c("fayalite", "enstatite", "ferrosilite", "forsterite") coeffs <- c(-1, -2, 2, 1) T <- seq(600, 1500, 50) Gex_Ber88 <- subcrt(species, coeffs, T = T, P = 1)$out$G # Add data from BA96 datadir <- system.file("extdata/Berman/testing", package = "CHNOSZ") add.OBIGT(file.path(datadir, "BA96_OBIGT.csv")) thermo("opt$Berman" = file.path(datadir, "BA96_Berman.csv")) Gex_BA96 <- subcrt(species, coeffs, T = seq(600, 1500, 50), P = 1)$out$G # Ber88 is lower than BA96 at low T (Gex_BA96 - Gex_Ber88)[1] > 0 # TRUE # The curves cross at about 725 deg C (BA96 Fig. 8) # (actually, in our calculation they cross closer to 800 deg C) T[which.min(abs(Gex_BA96 - Gex_Ber88))] # 800 # Reset the database (thermo()$OBIGT, and thermo()$opt$Berman) reset()
# Other than the formula, the parameters aren't stored in # thermo()$OBIGT, so this shows NAs info(info("quartz", "cr")) # Properties of alpha-quartz (aQz) at 298.15 K and 1 bar Berman("quartz") # Gibbs energies of aQz and coesite at higher T and P T <- seq(200, 1300, 100) P <- seq(22870, 31900, length.out = length(T)) G_aQz <- Berman("quartz", T = T, P = P)$G G_Cs <- Berman("coesite", T = T, P = P)$G # That is close to the univariant curve (Ber88 Fig. 4), # so the difference in G is close to 0 DGrxn <- G_Cs - G_aQz all(abs(DGrxn) < 100) # TRUE # Make a P-T diagram for SiO2 minerals (Ber88 Fig. 4) basis(c("SiO2", "O2"), c("cr", "gas")) species(c("quartz", "quartz,beta", "coesite"), "cr") a <- affinity(T = c(200, 1700, 200), P = c(0, 50000, 200)) diagram(a) ## Getting data from a user-supplied file ## Ol-Opx exchange equilibrium, after Berman and Aranovich, 1996 species <- c("fayalite", "enstatite", "ferrosilite", "forsterite") coeffs <- c(-1, -2, 2, 1) T <- seq(600, 1500, 50) Gex_Ber88 <- subcrt(species, coeffs, T = T, P = 1)$out$G # Add data from BA96 datadir <- system.file("extdata/Berman/testing", package = "CHNOSZ") add.OBIGT(file.path(datadir, "BA96_OBIGT.csv")) thermo("opt$Berman" = file.path(datadir, "BA96_Berman.csv")) Gex_BA96 <- subcrt(species, coeffs, T = seq(600, 1500, 50), P = 1)$out$G # Ber88 is lower than BA96 at low T (Gex_BA96 - Gex_Ber88)[1] > 0 # TRUE # The curves cross at about 725 deg C (BA96 Fig. 8) # (actually, in our calculation they cross closer to 800 deg C) T[which.min(abs(Gex_BA96 - Gex_Ber88))] # 800 # Reset the database (thermo()$OBIGT, and thermo()$opt$Berman) reset()
Calculate values of activity or fugacity of basis species buffered by an assemblage of one or more species.
mod.buffer(name, species = NULL, state = "cr", logact = 0)
mod.buffer(name, species = NULL, state = "cr", logact = 0)
name |
character, name of buffer to add to or find in |
species |
character, names or formulas of species in a buffer. |
state |
character, physical states of species in buffer. |
logact |
numeric, logarithms of activities of species in buffer. |
A buffer is treated here as assemblage of one or more species whose presence constrains values of the chemical activity (or fugacity) of one or more basis species.
To perform calculations for buffers use basis
to associate the name of the buffer with one or more basis species.
After this, calls to affinity
will invoke the required calculations.
The calculated values of the buffered activites can be retrieved by setting return.buffer
to TRUE
(in affinity
).
The maximum number of buffered chemical activities possible for any buffer is equal to the number of species in the buffer; however, the user may then elect to work with the values for only one or some of the basis species calculated with the buffer.
The identification of a conserved basis species (or other reaction balancing rule) is required in calculations for buffers of more than one species.
For example, in the pyrite-pyrrhotite-magnetite buffer (-
-
) a basis species common to each species is one representing
.
Therefore, when writing reactions between the species in this buffer
is conserved while
and
are the variables of interest.
The calculation for buffers attempts to determine which of the available basis species qualifies as a conserved quantity.
This can be overriden with
balance
.
The default value of balance
is ‘PBB’, which instructs the function to use the protein backbone group as the conserved quantity in buffers consisting of proteins, but has no overriding effect on the computations for buffers without proteins.
To view the available buffers, print the thermo()$buffer
object.
Buffer definitions can be added to this dataframe with mod.buffer
.
The defaults for state
and logact
are intended for mineral buffers.
If name
identifies an already defined buffer, this function modifies the logarithms of activities or states of species in that buffer, optionally restricted to only those species given in species
.
It is possible to assign different buffers to different basis species, in which case the order of their calculation depends on their order in thermo()$buffers
.
This function is compatible with systems of proteins, but note that for buffers made of proteins the buffer calculations presently use whole protein formulas (instead of residue equivalents) and consider nonionized proteins only.
Garrels, R. M. (1960) Mineral Equilibria. Harper & Brothers, New York, 254 p. https://www.worldcat.org/oclc/552690
diagram
with type
set to the name of a basis species solves for the activity of the basis species.
## List the buffers thermo()$buffer # Another way to do it, for a specific buffer print(mod.buffer("PPM")) ## Buffer made of one species # Calculate the activity of CO2 in equilibrium with # (a buffer made of) acetic acid at a given activity basis("CHNOS") basis("CO2", "AC") # What activity of acetic acid are we using? print(mod.buffer("AC")) # Return the activity of CO2 affinity(return.buffer = TRUE)$CO2 # -7.057521 # As a function of oxygen fugacity affinity(O2 = c(-85, -70, 4), return.buffer = TRUE) # As a function of logfO2 and temperature affinity(O2 = c(-85, -70, 4), T = c(25, 100, 4), return.buffer = TRUE) # Change the activity of species in the buffer mod.buffer("AC", logact = -10) affinity(O2 = c(-85,-70,4), T = c(25, 100, 4), return.buffer = TRUE) ## Buffer made of three species ## Pyrite-Pyrrhotite-Magnetite (PPM) # Specify basis species and initial activities basis(c("FeS2", "H2S", "O2", "H2O"), c(0, -10, -50, 0)) # Note that the affinity of formation of pyrite, # which corresponds to FeS2 in the basis, is zero species(c("pyrite", "pyrrhotite", "magnetite")) affinity(T = c(200, 400, 11), P = 2000)$values # Setup H2S and O2 to be buffered by PPM basis(c("H2S", "O2"), c("PPM", "PPM")) # Inspect values of H2S activity and O2 fugacity affinity(T = c(200, 400, 11), P = 2000, return.buffer = TRUE, exceed.Ttr = TRUE) # Calculate affinities of formation reactions of species in the buffer a <- affinity(T = c(200, 400, 11), P = 2000, exceed.Ttr = TRUE)$values # The affinities for species in the buffer are all equal to zero all.equal(as.numeric(a[[1]]), rep(0, 11)) # TRUE all.equal(as.numeric(a[[2]]), rep(0, 11)) # TRUE all.equal(as.numeric(a[[3]]), rep(0, 11)) # TRUE ## Buffer made of one species: show values of logfO2 on an ## Eh-pH diagram; after Garrels, 1960, Figure 6 basis("CHNOSe") # Here we will buffer the activity of the electron by O2 mod.buffer("O2", "O2", "gas", 999) basis("e-", "O2") # Start our plot, then loop over values of logfO2 thermo.plot.new(xlim = c(0, 14), ylim = c(-0.8, 1.2), xlab = "pH",ylab = axis.label("Eh")) # The upper and lower lines correspond to the upper # and lower stability limits of water logfO2 <- c(0, -20, -40, -60, -83.1) for(i in 1:5) { # Update the logarithm of fugacity (logact) of O2 in the buffer mod.buffer("O2", "O2", "gas", logfO2[i]) # Get the values of the logarithm of activity of the electron a <- affinity(pH = c(0, 14, 15), return.buffer = TRUE) # Convert values of pe (-logact of the electron) to Eh Eh <- convert(-as.numeric(a$`e-`), "Eh") lines(seq(0, 14, length.out = 15), Eh) # Add some labels text(seq(0, 14, length.out = 15)[i*2+2], Eh[i*2+2], paste("logfO2 =", logfO2[i])) } title(main = paste("Relation between logfO2(g), Eh and pH at\n", "25 degC and 1 bar. After Garrels, 1960")) ## Buffer made of two species # Conditions for metastable equilibrium among # CO2 and acetic acid. note their starting activities: print(mod.buffer("CO2-AC")) basis("CHNOS") basis("O2", "CO2-AC") affinity(return.buffer = TRUE) # logfO2 = -75.94248 basis("CO2", 123) # what the buffer reactions are balanced on affinity(return.buffer = TRUE) # unchanged # Consider more oxidizing conditions mod.buffer("CO2-AC", logact = c(0, -10)) affinity(return.buffer = TRUE)
## List the buffers thermo()$buffer # Another way to do it, for a specific buffer print(mod.buffer("PPM")) ## Buffer made of one species # Calculate the activity of CO2 in equilibrium with # (a buffer made of) acetic acid at a given activity basis("CHNOS") basis("CO2", "AC") # What activity of acetic acid are we using? print(mod.buffer("AC")) # Return the activity of CO2 affinity(return.buffer = TRUE)$CO2 # -7.057521 # As a function of oxygen fugacity affinity(O2 = c(-85, -70, 4), return.buffer = TRUE) # As a function of logfO2 and temperature affinity(O2 = c(-85, -70, 4), T = c(25, 100, 4), return.buffer = TRUE) # Change the activity of species in the buffer mod.buffer("AC", logact = -10) affinity(O2 = c(-85,-70,4), T = c(25, 100, 4), return.buffer = TRUE) ## Buffer made of three species ## Pyrite-Pyrrhotite-Magnetite (PPM) # Specify basis species and initial activities basis(c("FeS2", "H2S", "O2", "H2O"), c(0, -10, -50, 0)) # Note that the affinity of formation of pyrite, # which corresponds to FeS2 in the basis, is zero species(c("pyrite", "pyrrhotite", "magnetite")) affinity(T = c(200, 400, 11), P = 2000)$values # Setup H2S and O2 to be buffered by PPM basis(c("H2S", "O2"), c("PPM", "PPM")) # Inspect values of H2S activity and O2 fugacity affinity(T = c(200, 400, 11), P = 2000, return.buffer = TRUE, exceed.Ttr = TRUE) # Calculate affinities of formation reactions of species in the buffer a <- affinity(T = c(200, 400, 11), P = 2000, exceed.Ttr = TRUE)$values # The affinities for species in the buffer are all equal to zero all.equal(as.numeric(a[[1]]), rep(0, 11)) # TRUE all.equal(as.numeric(a[[2]]), rep(0, 11)) # TRUE all.equal(as.numeric(a[[3]]), rep(0, 11)) # TRUE ## Buffer made of one species: show values of logfO2 on an ## Eh-pH diagram; after Garrels, 1960, Figure 6 basis("CHNOSe") # Here we will buffer the activity of the electron by O2 mod.buffer("O2", "O2", "gas", 999) basis("e-", "O2") # Start our plot, then loop over values of logfO2 thermo.plot.new(xlim = c(0, 14), ylim = c(-0.8, 1.2), xlab = "pH",ylab = axis.label("Eh")) # The upper and lower lines correspond to the upper # and lower stability limits of water logfO2 <- c(0, -20, -40, -60, -83.1) for(i in 1:5) { # Update the logarithm of fugacity (logact) of O2 in the buffer mod.buffer("O2", "O2", "gas", logfO2[i]) # Get the values of the logarithm of activity of the electron a <- affinity(pH = c(0, 14, 15), return.buffer = TRUE) # Convert values of pe (-logact of the electron) to Eh Eh <- convert(-as.numeric(a$`e-`), "Eh") lines(seq(0, 14, length.out = 15), Eh) # Add some labels text(seq(0, 14, length.out = 15)[i*2+2], Eh[i*2+2], paste("logfO2 =", logfO2[i])) } title(main = paste("Relation between logfO2(g), Eh and pH at\n", "25 degC and 1 bar. After Garrels, 1960")) ## Buffer made of two species # Conditions for metastable equilibrium among # CO2 and acetic acid. note their starting activities: print(mod.buffer("CO2-AC")) basis("CHNOS") basis("O2", "CO2-AC") affinity(return.buffer = TRUE) # logfO2 = -75.94248 basis("CO2", 123) # what the buffer reactions are balanced on affinity(return.buffer = TRUE) # unchanged # Consider more oxidizing conditions mod.buffer("CO2-AC", logact = c(0, -10)) affinity(return.buffer = TRUE)
Calculate thermodynamic properties of water using the Deep Earth Water (DEW) model.
calculateDensity(pressure, temperature, error = 0.01) calculateGibbsOfWater(pressure, temperature) calculateEpsilon(density, temperature) calculateQ(density, temperature)
calculateDensity(pressure, temperature, error = 0.01) calculateGibbsOfWater(pressure, temperature) calculateEpsilon(density, temperature) calculateQ(density, temperature)
pressure |
numeric, pressure (bar) |
temperature |
numeric, temperature (°C) |
error |
numeric, residual error for bisection calculation |
density |
numeric, density (g/cm^3) |
The Deep Earth Water (DEW) model, described by Sverjensky et al., 2014, extends the applicability of the revised HKF equations of state to 60 kbar. This implementation of DEW is based on the VBA macro code in the May, 2017 version of the DEW spreadsheet downloaded from http://www.dewcommunity.org/. The spreadsheet provides multiple options for some calculations; here the default equations for density of water (Zhang and Duan, 2005), dielectric constant (Sverjensky et al., 2014) and Gibbs energy of water (integral of volume, equation created by Brandon Harrison) are used.
Comments in the original code indicate that calculateGibbsOfWater
is valid for 100 ≤ T ≤ 1000 °C and P ≥ 1000 bar.
Likewise, the power function fit of the dielectric constant (epsilon) is valid for 100 ≤ T ≤ 1200 °C and P ≥ 1000 bar (Sverjensky et al., 2014).
The calculated values of density, Gibbs energy, and the Q Born coefficient have units of g/cm^3, cal/mol, and bar^-1 (epsilon is dimensionless).
Sverjensky, D. A., Harrison, B. and Azzolini, D. (2014) Water in the deep Earth: The dielectric constant and the solubilities of quartz and corundum to 60 kb and 1,200 °C. Geochim. Cosmochim. Acta 129, 125–145. doi:10.1016/j.gca.2013.12.019
Zhang, Z. and Duan, Z. (2005) Prediction of the PVT properties of water over wide range of temperatures and pressures from molecular dynamics simulation. Phys. Earth Planet. Inter. 149, 335–354. doi:10.1016/j.pepi.2004.11.003
water.DEW
; use water("DEW")
to activate these equations for the main functions in CHNOSZ.
pressure <- c(1000, 60000) temperature <- c(100, 1000) calculateGibbsOfWater(pressure, temperature) (density <- calculateDensity(pressure, temperature)) calculateEpsilon(density, temperature) calculateQ(density, temperature)
pressure <- c(1000, 60000) temperature <- c(100, 1000) calculateGibbsOfWater(pressure, temperature) (density <- calculateDensity(pressure, temperature)) calculateEpsilon(density, temperature) calculateQ(density, temperature)
Plot equilibrium chemical activity (1-D speciation) or equal-activity (2-D predominance) diagrams as a function of chemical activities of basis species, temperature and/or pressure.
diagram( # species affinities or activities eout, # type of plot type = "auto", alpha = FALSE, normalize = FALSE, as.residue = FALSE, balance = NULL, groups = as.list(1:length(eout$values)), # figure size and sides for axis tick marks xrange = NULL, mar = NULL, yline = par("mgp")[1]+0.3, side = 1:4, # axis limits and labels ylog = TRUE, xlim = NULL, ylim = NULL, xlab = NULL, ylab = NULL, # character sizes cex = par("cex"), cex.names = 1, cex.axis = par("cex"), # line styles lty = NULL, lty.cr = NULL, lty.aq = NULL, lwd = par("lwd"), dotted = NULL, spline.method = NULL, contour.method = "edge", levels = NULL, # colors col = par("col"), col.names = par("col"), fill = NULL, fill.NA = "gray80", limit.water = NULL, # field and line labels names = NULL, format.names = TRUE, bold = FALSE, italic = FALSE, font = par("font"), family = par("family"), adj = 0.5, dx = 0, dy = 0, srt = 0, min.area = 0, # title and legend main = NULL, legend.x = NA, # plotting controls add = FALSE, plot.it = TRUE, tplot = TRUE, ...) find.tp(x)
diagram( # species affinities or activities eout, # type of plot type = "auto", alpha = FALSE, normalize = FALSE, as.residue = FALSE, balance = NULL, groups = as.list(1:length(eout$values)), # figure size and sides for axis tick marks xrange = NULL, mar = NULL, yline = par("mgp")[1]+0.3, side = 1:4, # axis limits and labels ylog = TRUE, xlim = NULL, ylim = NULL, xlab = NULL, ylab = NULL, # character sizes cex = par("cex"), cex.names = 1, cex.axis = par("cex"), # line styles lty = NULL, lty.cr = NULL, lty.aq = NULL, lwd = par("lwd"), dotted = NULL, spline.method = NULL, contour.method = "edge", levels = NULL, # colors col = par("col"), col.names = par("col"), fill = NULL, fill.NA = "gray80", limit.water = NULL, # field and line labels names = NULL, format.names = TRUE, bold = FALSE, italic = FALSE, font = par("font"), family = par("family"), adj = 0.5, dx = 0, dy = 0, srt = 0, min.area = 0, # title and legend main = NULL, legend.x = NA, # plotting controls add = FALSE, plot.it = TRUE, tplot = TRUE, ...) find.tp(x)
eout |
list, object returned by |
type |
character, type of plot, or name of basis species whose activity to plot |
alpha |
logical or character (‘balance’), for speciation diagrams, plot degree of formation instead of activities? |
normalize |
logical, divide chemical affinities by balance coefficients and rescale activities to whole formulas? |
as.residue |
logical, divide chemical affinities by balance coefficients (no rescaling)? |
balance |
character, balancing constraint; see |
groups |
list of numeric, groups of species to consider as a single effective species |
xrange |
numeric, range of x-values between which predominance field boundaries are plotted |
mar |
numeric, margins of plot frame |
yline |
numeric, margin line on which to plot the y-axis name |
side |
numeric, which sides of plot to draw axes |
xlim |
numeric, limits of x-axis |
ylim |
numeric, limits of y-axis |
xlab |
character, label to use for x-axis |
ylab |
character, label to use for y-axis |
ylog |
logical, use a logarithmic y-axis (on 1D degree diagrams)? |
cex |
numeric, character expansion (scaling relative to current) |
cex.names |
numeric, character expansion factor to be used for names of species on plots |
cex.axis |
numeric, character expansion factor for names of axes |
lty |
numeric, line types to be used in plots |
lty.cr |
numeric, line types for cr-cr boundaries (between two minerals) |
lty.aq |
numeric, line types for aq-aq boundaries (between two aqueous species) |
lwd |
numeric, line width |
dotted |
numeric, how often to skip plotting points on predominance field boundaries (to gain the effect of dotted or dashed boundary lines) |
spline.method |
character, method used in |
contour.method |
character, labelling method used in |
levels |
numeric, levels at which to draw contour lines |
col |
character, color of activity lines (1D diagram) or predominance field boundaries (2D diagram) |
col.names |
character, colors for labels of species |
fill |
character, colors used to fill predominance fields |
fill.NA |
character, color for grid points with NA values |
limit.water |
NULL or logical, set NA values beyond water stability limits? |
names |
character, names of species for activity lines or predominance fields |
format.names |
logical, apply formatting to chemical formulas? |
bold |
logical, use bold formatting for names? |
italic |
logical, use italic formatting for names? |
font |
character, font type for names (has no effect if |
family |
character, font family for names |
adj |
numeric, adjustment for line labels |
dx |
numeric, x offset for line or field labels |
dy |
numeric, y offset for line or field labels |
srt |
numeric, rotation for line labels |
min.area |
numeric, minimum area of fields that should be labeled, expressed as a fraction of the total plot area |
main |
character, a main |
legend.x |
character, description of legend placement passed to |
add |
logical, add to current plot? |
plot.it |
logical, make a plot? |
tplot |
logical, set up plot with |
x |
matrix, value of the |
... |
This function displays diagrams representing either chemical affinities or equilibrium chemical activities of species.
The first argument is the output from affinity
, rank.affinity
, equilibrate
, or solubility
.
0-D diagrams, at a single point, are shown as barplot
s.
1-D diagrams, for a single variable on the x-axis, are plotted as lines.
2-D diagrams, for two variables, are plotted as predominance fields.
The allowed variables are any that affinity
or the other functions accepts: temperature, pressure, or the chemical activities of the basis species.
A new plot is started unless add
is TRUE.
If plot.it
is FALSE, no plot will be generated but all the intermediate computations will be performed and the results returned.
Line or field labels use the names of the species as provided in eout
; formatting is applied to chemical formulas (see expr.species
) unless format.names
is FALSE.
Set names
to TRUE or NULL to plot the names, or FALSE, NA, or ""
to prevent plotting the names, or a character argument to replace the default species names.
Alternatively, supply a numeric value to names
to indicate a subset of default names that should or shouldn't be plotted (positive and negative indices, respectively).
Use col.names
and cex.names
to change the colors and size of the labels.
Use cex
and cex.axis
to adjust the overall character expansion factors (see par
) and those of the axis labels.
The x- and y-axis labels are automatically generated unless they are supplied in xlab
and ylab
.
If groups
is supplied, the activities of the species identified in each numeric element of this list are multiplied by the balance coefficients of the species, then summed together.
The names of the list are used to label the lines or fields for the summed activities of the resulting groups.
Normalizing protein formulas by length gives “residue equivalents” (Dick and Shock, 2011) that are useful for equilibrium calculations with proteins.
normalize
and as.residue
are only usable when eout
is the output from affinity
, and only one can be TRUE.
If normalize
is TRUE, formation reactions and their affinities are first divided by protein length, so equal activities of residue equivalents are considered; then, the residue activities are rescaled to whole proteins for making the plot.
If as.residue
is TRUE, no rescaling is performed, so the diagram represents activities of the residues, not the whole proteins.
type
argumentThis paragraph describes the effect of the type
argument when the output from affinity
is being used.
For type
set to ‘auto’, and with 0 or 1 variables defined in affinity
, the property computed by affinity
for each species is plotted.
This is usually the affinity of the formation reactions, but can be set to some other property (using the property
argument of affinity
), such as the equilibrium constant (‘logK’).
For two variables, equilibrium predominance (maximum affinity) fields are plotted.
This “maximum affinity method” (Dick, 2019) uses balancing coefficients that are specified by the balance
argument.
If type
is ‘saturation’, the function plots the line for each species where the affinity of formation equals zero (see demo("saturation")
for an example).
If for a given species no saturation line is possible or the range of the diagram does not include the saturation line, the function prints a message instead.
If type
is the name of a basis species, then the equilibrium activity of the selected basis species in each of the formation reactions is plotted (see the CO2-acetic acid example in buffer
).
In the case of 2-D diagrams, both of these options use contour
to draw the lines, with the method specified in contour.method
.
This paragraph describes the effect of the type
argument when the output from solubility
is being used.
For one mineral or gas, if type
set to ‘auto’, the equilibrium activities of each aqueous species are plotted.
If type
is ‘loga.balance’, the activity of the balancing basis species (i.e. total solubility) is plotted; this is represented by contours on a 2-D diagram.
For two or more minerals or gases, if type
set to ‘auto’, the values of ‘loga.balance’ (overall minimum solubility) are plotted.
If type
is ‘loga.equil’, the solubilities of the individual minerals and gases are plotted.
For examples that use these features, see solubility
and various demos
: ‘DEW’, ‘contour’, ‘gold’, ‘solubility’, ‘sphalerite’.
For 1-D diagrams, the default setting for the y-axis is a logarithmic scale (unless alpha
is TRUE) with limits corresponding to the range of logarithms of activities (or 0,1 if alpha
is TRUE); these actions can be overridden by ylog
and ylim
.
If legend.x
is NA (the default), the lines are labeled with the names of the species near the maximum value.
Otherwise, a legend
is placed at the location identified by legend.x
, or omitted if legend.x
is NULL.
If alpha
is TRUE, the fractional degrees of formation (ratios of activities to total activity) are plotted.
Or, setting alpha
to ‘balance’ allows the activities to be multiplied by the number of the balancing component; this is useful for making “percent carbon” diagrams where the species differ in carbon number.
The line type and line width can be controlled with lty
and lwd
, respectively.
To connect the points with splines instead of lines, set spline.method
to one of the methods in splinefun
.
On 2-D diagrams, the fields represent the species with the highest equilibrium activity.
fill
determines the color of the predominance fields, col
that of the boundary lines.
The default of NULL for fill
uses a light blue, light tan, and darker tan color for fields with aqueous species, one solid, or two solids.
These correspond to the web colors "aliceblue", "antiquewhite", and "burlywood" with some transparency added; see multi-metal for an example with two solids produced using mix
.
If all the species in the diagram have the same state, or if the fill
argument is NA or a 0-length value, the predominance fields are transparent, i.e. no fill color is used.
Otherwise, fill
can be any colors
, or the word ‘rainbow’, ‘heat’, ‘terrain’, ‘topo’, or ‘cm’, indicating a palette from grDevices.
Starting with R version 3.6.0, fill
can be the name of any available HCL color palette, matched in the same way as the palette
argument of hcl.colors
.
fill.NA
gives the color for empty fields, i.e. points at which NA values are present for any species.
This may occur when there are missing thermodynamic data or the temperature or pressure are not in the range of the equations of state.
To make overlay diagrams easier to construct, the default for fill.NA
is automatically changed to ‘transparent’ when add
is TRUE.
If limit.water
is TRUE, the diagram is clipped to the the water stability region on Eh-pH (and some other) diagrams.
That is, predominance fields are shown only where water is stable, and fill.NA
is used for areas where H2O is not stable.
The default of NULL for limit.water
does not clip the main diagram but instead overlays it on the water stability fields.
Change limit.water
to FALSE to not show the water stability regions at all; this is automatically done if limit.water
is missing and add
is TRUE.
The default line-drawing algorithm uses contourLines
to obtain smooth-looking diagonal and curved lines, at the expense of not coinciding exactly with the rectangular grid that is used for drawing colors.
lty
, col
, and lwd
can be specified, but limiting the lines via xrange
is not currently supported.
Set lty.cr
or lty.aq
to 0 to suppress boundary lines between minerals or aqueous species.
To go back to the old behavior for drawing lines, set dotted
to ‘0’.
The old behavior does not respect lty
; instead, the style of the boundary lines on 2-D diagrams can be altered by supplying one or more non-zero integers in dotted
, which indicates the fraction of line segments to omit; a value of ‘1’ or NULL for dotted
has the effect of not drawing the boundary lines.
The wording in this page and names of variables in functions refer exclusively to ‘activities’ of aqueous species.
However, if activity coefficients are calculated (using the IS
argument in affinity
), then these variables are effectively transformed to molalities (see inst/tinytest/test-logmolality.R
).
So that the labels on diagrams are adjusted accordingly, diagram
sets the molality
argument of axis.label
to TRUE if IS
was supplied as an argument to affinity
.
The labeling as molality takes effect even if IS
is set to 0; this way, by including (or not) the IS = 0
argument to affinity
, the user decides whether to label aqueous species variables as molality (or activity) for calculations at zero ionic strength (where molality = activity).
find.tp
finds the locations in a matrix of integers that are surrounded by the greatest number of different values.
The function counts the unique values in a 3x3 grid around each point and returns a matrix of indices (similar to which(..., arr.ind = TRUE)
) for the maximum count (ties result in more than one pair of indices).
It can be used with the output from diagram
for calculations in 2 dimensions to approximately locate the triple points on the diagram.
diagram
returns an invisible
list containing, first, the contents of eout
, i.e. the output of affinity
or equilibrate
supplied in the function call.
To this are added the names of the plotted variable in plotvar
, the labels used for species (which may be plotmath
expressions if format.names
is TRUE) in names
, and the values used for plotting in a list named plotvals
.
For 1-D diagrams, plotvals
usually corresponds to the chemical activities of the species (i.e. eout$loga.equil
), or, if alpha
is TRUE
, their mole fractions (degrees of formation).
For 2-D diagrams, plotvals
corresponds to the values of affinity (from eout$values
) divided by the respective balancing coefficients for each species.
For 2-D diagrams, the output also contains the matrices predominant
, which identifies the predominant species in eout$species
at each grid point, and predominant.values
, which has the affinities of the predominant species divided by the balancing coefficients (if eout
is the output of affinity
) or the activities of the predominant species (if eout
is the output of equilibrate
).
The rows and columns of these matrices correspond to the x and y variables, respectively.
Finally, the output for 2-D diagrams contains a lines
component, giving the x- and y-coordinates of the field boundaries computed using contourLines
; the values are padded to equal length with NAs to faciliate exporting the results using write.csv
.
Aksu, S. and Doyle, F. M. (2001) Electrochemistry of copper in aqueous glycine solutions. J. Electrochem. Soc. 148, B51–B57.
Dick, J. M. (2019) CHNOSZ: Thermodynamic calculations and diagrams for geochemistry. Front. Earth Sci. 7:180. doi:10.3389/feart.2019.00180
Dick, J. M. and Shock, E. L. (2011) Calculation of the relative chemical stabilities of proteins as a function of temperature and redox chemistry in a hot spring. PLOS One 6, e22782. doi:10.1371/journal.pone.0022782
Helgeson, H. C. (1970) A chemical and thermodynamic model of ore deposition in hydrothermal systems. Mineral. Soc. Amer. Spec. Pap. 3, 155–186. https://www.worldcat.org/oclc/583263
Helgeson, H. C., Delany, J. M., Nesbitt, H. W. and Bird, D. K. (1978) Summary and critique of the thermodynamic properties of rock-forming minerals. Am. J. Sci. 278-A, 1–229. https://www.worldcat.org/oclc/13594862
LaRowe, D. E. and Helgeson, H. C. (2007) Quantifying the energetics of metabolic reactions in diverse biogeochemical systems: electron flow and ATP synthesis. Geobiology 5, 153–168. doi:10.1111/j.1472-4669.2007.00099.x
Majzlan, J., Navrotsky, A., McClesky, R. B. and Alpers, C. N. (2006) Thermodynamic properties and crystal structure refinement of ferricopiapite, coquimbite, rhomboclase, and Fe2(SO4)3(H2O)5. Eur. J. Mineral. 18, 175–186. doi:10.1127/0935-1221/2006/0018-0175
Tagirov, B. and Schott, J. (2001) Aluminum speciation in crustal fluids revisited. Geochim. Cosmochim. Acta 65, 3965–3992. doi:10.1016/S0016-7037(01)00705-0
Berman
, mix
, mosaic
, nonideal
, solubility
, and util.plot
are other help topics that use diagram
in their examples.
See the demos
for even more examples.
## Calculate the equilibrium logarithm of activity of a ## basis species in different reactions basis("CHNOS") species(c("ethanol", "lactic acid", "deoxyribose", "ribose")) a <- affinity(T = c(0, 150)) diagram(a, type = "O2", legend.x = "topleft", col = rev(rainbow(4)), lwd = 2) title(main = "Equilibrium logfO2 for 1e-3 mol/kg of CO2 and ... ") ### 1-D diagrams: logarithms of activities ## Degrees of formation of ionized forms of glycine ## After Fig. 1 of Aksu and Doyle, 2001 basis("CHNOS+") species(ispecies <- info(c("glycinium", "glycine", "glycinate"))) a <- affinity(pH = c(0, 14)) e <- equilibrate(a) diagram(e, alpha = TRUE, lwd = 1) title(main = paste("Degrees of formation of aqueous glycine species\n", "after Aksu and Doyle, 2001")) ## Degrees of formation of ATP species as a function of ## temperature, after LaRowe and Helgeson, 2007, Fig. 10b # to make a similar diagram, activity of Mg+2 here is set to # 10^-4, which is different from LH07, who used 10^-3 total molality basis(c("CO2", "NH3", "H2O", "H3PO4", "O2", "H+", "Mg+2"), c(999, 999, 999, 999, 999, -5, -4)) species(c("HATP-3", "H2ATP-2", "MgATP-2", "MgHATP-")) a <- affinity(T = c(0, 120, 25)) e <- equilibrate(a) diagram(e, alpha = TRUE) title(main = paste("Degrees of formation of ATP species,\n", "pH=5, log(aMg+2)=-3. After LaRowe and Helgeson, 2007"), cex.main = 0.9) ### 2-D diagrams: predominance diagrams ### These use the maximum affinity method ## Fe-S-O at 200 deg C, after Helgeson, 1970 basis(c("Fe", "oxygen", "S2")) species(c("iron", "ferrous-oxide", "magnetite", "hematite", "pyrite", "pyrrhotite")) # The calculations include the polymorphic transitions of # pyrrhotite; no additional step is needed a <- affinity(S2 = c(-50, 0), O2 = c(-90, -10), T=200) diagram(a, fill = "heat") title(main = paste("Fe-S-O, 200 degrees C, 1 bar", "After Helgeson, 1970", sep = "\n")) ## pe-pH diagram for hydrated iron sulfides, ## goethite and pyrite, after Majzlan et al., 2006 basis(c("Fe+2", "SO4-2", "H2O", "H+", "e-"), c(0, log10(3), log10(0.75), 999, 999)) species(c("rhomboclase", "ferricopiapite", "hydronium jarosite", "goethite", "melanterite", "pyrite")) a <- affinity(pH = c(-1, 4, 256), pe = c(-5, 23, 256)) d <- diagram(a, main = "Fe-S-O-H, after Majzlan et al., 2006") water.lines(d, lwd = 2) text(3, 22, describe.basis(2:3, digits = 2, oneline = TRUE)) text(3, 21, describe.property(c("T", "P"), c(25, 1), oneline = TRUE)) ## Aqueous Al species, after Tagirov and Schott, 2001 basis(c("Al+3", "F-", "H+", "O2", "H2O")) AlOH <- c("Al(OH)4-", "Al(OH)3", "Al(OH)2+", "AlOH+2") Al <- "Al+3" AlF <- c("AlF+2", "AlF2+", "AlF3", "AlF4-") AlOHF <- c("Al(OH)2F2-", "Al(OH)2F", "AlOHF2") species(c(AlOH, Al, AlF, AlOHF), "aq") res <- 300 a <- affinity(pH = c(0.5, 6.5, res), `F-` = c(-2, -9, res), T = 200) diagram(a, fill = "terrain") dprop <- describe.property(c("T", "P"), c(200, "Psat")) legend("topright", legend = dprop, bty = "n") mtitle(c("Aqueous aluminum species", "After Tagirov and Schott, 2001 Fig. 4d"), cex = 0.95) ## Temperature-Pressure: kayanite-sillimanite-andalusite # cf. Fig. 49 of Helgeson et al., 1978 # this is a system of one component (Al2SiO5), however: # - number of basis species must be the same as of elements # - avoid using H2O or other aqueous species because of # T/P limits of the water() calculations; basis(c("corundum", "quartz", "oxygen")) species(c("kyanite", "sillimanite", "andalusite")) # Database has transition temperatures of kyanite and andalusite # at 1 bar only, so we permit calculation at higher temperatures a <- affinity(T = c(200, 900, 99), P = c(0, 9000, 101), exceed.Ttr = TRUE) d <- diagram(a, fill = NULL) slab <- syslab(c("Al2O3", "SiO2", "H2O")) mtitle(c(as.expression(slab), "after Helgeson et al., 1978")) # Find the approximate position of the triple point tp <- find.tp(d$predominant) Ttp <- a$vals[[1]][tp[1, 2]] Ptp <- rev(a$vals[[2]])[tp[1, 1]] points(Ttp, Ptp, pch = 10, cex = 5)
## Calculate the equilibrium logarithm of activity of a ## basis species in different reactions basis("CHNOS") species(c("ethanol", "lactic acid", "deoxyribose", "ribose")) a <- affinity(T = c(0, 150)) diagram(a, type = "O2", legend.x = "topleft", col = rev(rainbow(4)), lwd = 2) title(main = "Equilibrium logfO2 for 1e-3 mol/kg of CO2 and ... ") ### 1-D diagrams: logarithms of activities ## Degrees of formation of ionized forms of glycine ## After Fig. 1 of Aksu and Doyle, 2001 basis("CHNOS+") species(ispecies <- info(c("glycinium", "glycine", "glycinate"))) a <- affinity(pH = c(0, 14)) e <- equilibrate(a) diagram(e, alpha = TRUE, lwd = 1) title(main = paste("Degrees of formation of aqueous glycine species\n", "after Aksu and Doyle, 2001")) ## Degrees of formation of ATP species as a function of ## temperature, after LaRowe and Helgeson, 2007, Fig. 10b # to make a similar diagram, activity of Mg+2 here is set to # 10^-4, which is different from LH07, who used 10^-3 total molality basis(c("CO2", "NH3", "H2O", "H3PO4", "O2", "H+", "Mg+2"), c(999, 999, 999, 999, 999, -5, -4)) species(c("HATP-3", "H2ATP-2", "MgATP-2", "MgHATP-")) a <- affinity(T = c(0, 120, 25)) e <- equilibrate(a) diagram(e, alpha = TRUE) title(main = paste("Degrees of formation of ATP species,\n", "pH=5, log(aMg+2)=-3. After LaRowe and Helgeson, 2007"), cex.main = 0.9) ### 2-D diagrams: predominance diagrams ### These use the maximum affinity method ## Fe-S-O at 200 deg C, after Helgeson, 1970 basis(c("Fe", "oxygen", "S2")) species(c("iron", "ferrous-oxide", "magnetite", "hematite", "pyrite", "pyrrhotite")) # The calculations include the polymorphic transitions of # pyrrhotite; no additional step is needed a <- affinity(S2 = c(-50, 0), O2 = c(-90, -10), T=200) diagram(a, fill = "heat") title(main = paste("Fe-S-O, 200 degrees C, 1 bar", "After Helgeson, 1970", sep = "\n")) ## pe-pH diagram for hydrated iron sulfides, ## goethite and pyrite, after Majzlan et al., 2006 basis(c("Fe+2", "SO4-2", "H2O", "H+", "e-"), c(0, log10(3), log10(0.75), 999, 999)) species(c("rhomboclase", "ferricopiapite", "hydronium jarosite", "goethite", "melanterite", "pyrite")) a <- affinity(pH = c(-1, 4, 256), pe = c(-5, 23, 256)) d <- diagram(a, main = "Fe-S-O-H, after Majzlan et al., 2006") water.lines(d, lwd = 2) text(3, 22, describe.basis(2:3, digits = 2, oneline = TRUE)) text(3, 21, describe.property(c("T", "P"), c(25, 1), oneline = TRUE)) ## Aqueous Al species, after Tagirov and Schott, 2001 basis(c("Al+3", "F-", "H+", "O2", "H2O")) AlOH <- c("Al(OH)4-", "Al(OH)3", "Al(OH)2+", "AlOH+2") Al <- "Al+3" AlF <- c("AlF+2", "AlF2+", "AlF3", "AlF4-") AlOHF <- c("Al(OH)2F2-", "Al(OH)2F", "AlOHF2") species(c(AlOH, Al, AlF, AlOHF), "aq") res <- 300 a <- affinity(pH = c(0.5, 6.5, res), `F-` = c(-2, -9, res), T = 200) diagram(a, fill = "terrain") dprop <- describe.property(c("T", "P"), c(200, "Psat")) legend("topright", legend = dprop, bty = "n") mtitle(c("Aqueous aluminum species", "After Tagirov and Schott, 2001 Fig. 4d"), cex = 0.95) ## Temperature-Pressure: kayanite-sillimanite-andalusite # cf. Fig. 49 of Helgeson et al., 1978 # this is a system of one component (Al2SiO5), however: # - number of basis species must be the same as of elements # - avoid using H2O or other aqueous species because of # T/P limits of the water() calculations; basis(c("corundum", "quartz", "oxygen")) species(c("kyanite", "sillimanite", "andalusite")) # Database has transition temperatures of kyanite and andalusite # at 1 bar only, so we permit calculation at higher temperatures a <- affinity(T = c(200, 900, 99), P = c(0, 9000, 101), exceed.Ttr = TRUE) d <- diagram(a, fill = NULL) slab <- syslab(c("Al2O3", "SiO2", "H2O")) mtitle(c(as.expression(slab), "after Helgeson et al., 1978")) # Find the approximate position of the triple point tp <- find.tp(d$predominant) Ttp <- a$vals[[1]][tp[1, 2]] Ptp <- rev(a$vals[[2]])[tp[1, 1]] points(Ttp, Ptp, pch = 10, cex = 5)
Fit experimental volumes and heat capacities using regression equations. Possible models include the Helgeson-Kirkham-Flowers (HKF) equations of state, or other equations defined using any combination of terms derived from the temperature, pressure and thermodynamic and electrostatic properties of water.
EOSregress(exptdata, var = "", T.max = 9999, ...) EOSvar(var, T, P, ...) EOScalc(coefficients, T, P, ...) EOSplot(exptdata, var = NULL, T.max = 9999, T.plot = NULL, fun.legend = "topleft", coefficients = NULL, add = FALSE, lty = par("lty"), col=par("col"), ...) EOSlab(var, coeff = "") EOScoeffs(species, property, P=1) Cp_s_var(T = 298.15, P = 1, omega.PrTr = 0, Z = 0) V_s_var(T = 298.15, P = 1, omega.PrTr = 0, Z = 0)
EOSregress(exptdata, var = "", T.max = 9999, ...) EOSvar(var, T, P, ...) EOScalc(coefficients, T, P, ...) EOSplot(exptdata, var = NULL, T.max = 9999, T.plot = NULL, fun.legend = "topleft", coefficients = NULL, add = FALSE, lty = par("lty"), col=par("col"), ...) EOSlab(var, coeff = "") EOScoeffs(species, property, P=1) Cp_s_var(T = 298.15, P = 1, omega.PrTr = 0, Z = 0) V_s_var(T = 298.15, P = 1, omega.PrTr = 0, Z = 0)
exptdata |
dataframe, experimental data |
var |
character, name(s) of variables in the regression equations |
T.max |
numeric, maximum temperature for regression, in degrees Kelvin |
T |
numeric, temperature in Kelvin |
P |
numeric, pressure in bars |
... |
arguments specifying additional dependencies of the regression variables |
T.plot |
numeric, upper limit of temperature range to plot |
fun.legend |
character, where to place legend on plot |
coefficients |
dataframe, coefficients to use to make line on plot |
add |
logical, add lines to an existing plot? |
lty |
line style |
col |
color of lines |
coeff |
numeric, value of equation of state parameter for plot legend |
species |
character, name of aqueous species |
property |
character, ‘Cp’ or ‘V’ |
omega.PrTr |
numeric, value of omega at reference T and P |
Z |
numeric, charge |
EOSregress
uses a linear model (lm
) to regress the experimental heat capacity or volume data in exptdata
, which is a data frame with columns ‘T’ (temperature in degrees Kelvin), ‘P’ (pressure in bars), and ‘Cp’ or ‘V’ (heat capacity in cal/mol.K or volume in cm3/mol).
The ‘Cp’ or ‘V’ data must be in the third column.
Only data below the temperature of T.max
are included in the regression.
The regression formula is specified by a vector of names in var
.
The names of the variables can be any combination of the following (listed in the order of search): variables listed in the following table, any available property of water
(e.g. ‘V’, ‘alpha’, ‘QBorn’), or the name of a function that can be found using get
in the default environment.
Examples of the latter are Cp_s_var
, V_s_var
, or functions defined by the user in the global environment; the arguments of these functions must include, but are not limited to, T
and P
.
T |
(temperature) |
P |
(pressure) |
TTheta |
( = 228 K) |
invTTheta |
|
TTheta2 |
|
invTTheta2 |
|
invPPsi |
( = 2600 bar) |
invPPsiTTheta |
|
TXBorn |
(temperature times Born function) |
drho.dT |
(temperature derivative of density of water) |
V.kT |
(volume times isothermal compressibility of water)
|
EOSvar
calculates the value of the variable named var
(defined as described above) at the specified T
(temperature in degrees Kelvin) and P
(pressure in bars).
This function is used by EOSregress
to get the values of the variables used in the regression.
EOScalc
calculates the predicted heat capacities or volumes using coefficients provided by the result of EOSregress
, at the temperatures and pressures specified by T
and P
.
EOSplot
takes a table of data in exptdata
, runs EOSregress
and EOScalc
and plots the results.
The experimental data are plotted as points, and the calculated values as a smooth line.
The point symbols are filled circles where the calculated value is within 10% of the experimental value; open circles otherwise.
EOSlab
produces labels for the variables listed above that can be used as.expression
s in plots.
The value of coeff
is prefixed to the name of the variable (using substitute
, with a multiplication symbol).
For the properties listed in the table above, and selected properties listed in water
, the label is formatted using plotmath
expressions (e.g., with italicized symbols and Greek letters).
If var
is a user-defined function, the function can be given a ‘label’ attribute to provide plotmath
-style formatting; in this case the appropriate multiplication or division symbol should be specified (see example below).
EOScoeffs
retrieves coefficients in the Helgeson-Kirkham-Flowers equations from the thermodynamic database (thermo$OBIGT
) for the given aqueous species
.
If the property
is ‘Cp’, the resulting data frame has column names of ‘(Intercept)’, ‘invTTheta2’ and ‘TX’, respectively holding the coefficients ,
and
in the equation
.
If the
property
is ‘V’, the data frame has column names of ‘(Intercept)’, ‘invTTheta’ and ‘Q’, respectively holding the coefficients ,
and
in
.
Here,
and
are calculated from a1, a2, a3 and a4 in
thermo()$OBIGT
at the pressure indicated by P
(default 1 bar).
The original motivation for writing these functions was to explore alternatives or possible modifications to the revised Helgeson-Kirkham-Flowers equations applied to aqueous nonelectrolytes.
As pointed out by Schulte et al., 2001, the functional forms of the equations do not permit retrieving values of the solvation parameter () that closely represent the observed trends in both heat capacity and volume at high temperatures (above ca. 200 °C).
The examples below assume that the parameter in the HKF functions is a constant (does not depend on T and P), as is appropriate for nonelectrolytes.
For charged species, the variables
Cp_s_var
and V_s_var
can be used in the regressions.
They correspond to the solvation contribution to heat capacity or volume, respectively, in the HKF EOS, divided by the value of at the reference temperature and pressure.
Because these variables are themselves a function of
omega.PrTr
, an iterative procedure is needed to perform the regression.
Note that variables QBorn
and V_s_var
are both negated, so that the value of has its proper sign in the corresponding equations.
For EOSregress
, an object of class “lm”.
EOSvar
and EOScalc
both return numeric values.
EOScoeffs
returns a data frame.
Hnědkovský, L. and Wood, R. H. (1997) Apparent molar heat capacities of aqueous solutions of CH4, CO2, H2S, and NH3 at temperatures from 304 K to 704 K at a pressure of 28 MPa. J. Chem. Thermodyn. 29, 731–747. doi:10.1006/jcht.1997.0192
Schulte, M. D., Shock, E. L. and Wood, R. H. (1995) The temperature dependence of the standard-state thermodynamic properties of aqueous nonelectrolytes. Geochim. Cosmochim. Acta 65, 3919–3930. doi:10.1016/S0016-7037(01)00717-7
The vignette eos-regress has more references and examples, including an iterative method to retrieve omega.PrTr
.
## Fit experimental heat capacities of CH4 ## using revised Helgeson-Kirkham-Flowers equations # Read the data from Hnedkovsky and Wood, 1997 f <- system.file("extdata/cpetc/HW97_Cp.csv", package = "CHNOSZ") d <- read.csv(f) # Use data for CH4 d <- d[d$species == "CH4", ] d <- d[, -1] # Convert J to cal and MPa to bar d$Cp <- convert(d$Cp, "cal") d$P <- convert(d$P, "bar") # Specify the terms in the HKF equations var <- c("invTTheta2", "TXBorn") # Perform regression, with a temperature limit EOSlm <- EOSregress(d, var, T.max = 600) # Calculate the Cp at some temperature and pressure EOScalc(EOSlm$coefficients, 298.15, 1) # Get the database values of c1, c2 and omega for CH4(aq) CH4coeffs <- EOScoeffs("CH4", "Cp") ## Make plots comparing the regressions ## with the accepted EOS parameters of CH4 opar <- par(mfrow = c(2,2)) EOSplot(d, T.max = 600) title("Cp of CH4(aq), fit to 600 K") legend("bottomleft", pch = 1, legend = "Hnedkovsky and Wood, 1997") EOSplot(d, coefficients = CH4coeffs) title("Cp from EOS parameters in database") EOSplot(d, T.max = 600, T.plot = 600) title("Cp fit to 600 K, plot to 600 K") EOSplot(d, coefficients = CH4coeffs, T.plot = 600) title("Cp from EOS parameters in database") par(opar) # Continuing from above, with user-defined variables Theta <- 228 # K invTTTheta3 <- function(T, P) (2*T) / (T-T*Theta) ^ 3 invTX <- function(T, P) 1 / T * water("XBorn", T = T, P = P)[,1] # Print the calculated values of invTTTheta3 EOSvar("invTTTheta3", d$T, d$P) # Use invTTTheta and invTX in a regression var <- c("invTTTheta3", "invTX") EOSregress(d, var) # Give them a "label" attribute for use in the legend attr(invTTTheta3, "label") <- quote(phantom()%*%2 * italic(T) / (italic(T) - italic(T) * Theta) ^ 3) attr(invTX, "label") <- quote(phantom() / italic(T * X)) # Uncomment the following to make the plot #EOSplot(d, var) ## Model experimental volumes of CH4 ## using HKF equation and an exploratory one f <- system.file("extdata/cpetc/HWM96_V.csv", package = "CHNOSZ") d <- read.csv(f) # Use data for CH4 near 280 bar d <- d[d$species == "CH4", ] d <- d[, -1] d <- d[abs(d$P - 28) < 0.1, ] d$P <- convert(d$P, "bar") # The HKF equation varHKF <- c("invTTheta", "QBorn") # alpha is the expansivity coefficient of water varal <- c("invTTheta", "alpha") opar <- par(mfrow = c(2, 2)) # For both HKF and the expansivity equation, # we'll fit up to a temperature limit EOSplot(d, varHKF, T.max = 663, T.plot = 625) legend("bottomright", pch = 1, legend = "Hnedkovsky et al., 1996") title("V of CH4(aq), HKF equation") EOSplot(d, varal, T.max = 663, T.plot = 625) title("V of CH4(aq), expansivity equation") EOSplot(d, varHKF, T.max = 663) title("V of CH4(aq), HKF equation") EOSplot(d, varal, T.max = 663) title("V of CH4(aq), expansivity equation") par(opar) # Note that the volume regression using the HKF gives # a result for omega (coefficient on Q) that is # not consistent with the high-T heat capacities
## Fit experimental heat capacities of CH4 ## using revised Helgeson-Kirkham-Flowers equations # Read the data from Hnedkovsky and Wood, 1997 f <- system.file("extdata/cpetc/HW97_Cp.csv", package = "CHNOSZ") d <- read.csv(f) # Use data for CH4 d <- d[d$species == "CH4", ] d <- d[, -1] # Convert J to cal and MPa to bar d$Cp <- convert(d$Cp, "cal") d$P <- convert(d$P, "bar") # Specify the terms in the HKF equations var <- c("invTTheta2", "TXBorn") # Perform regression, with a temperature limit EOSlm <- EOSregress(d, var, T.max = 600) # Calculate the Cp at some temperature and pressure EOScalc(EOSlm$coefficients, 298.15, 1) # Get the database values of c1, c2 and omega for CH4(aq) CH4coeffs <- EOScoeffs("CH4", "Cp") ## Make plots comparing the regressions ## with the accepted EOS parameters of CH4 opar <- par(mfrow = c(2,2)) EOSplot(d, T.max = 600) title("Cp of CH4(aq), fit to 600 K") legend("bottomleft", pch = 1, legend = "Hnedkovsky and Wood, 1997") EOSplot(d, coefficients = CH4coeffs) title("Cp from EOS parameters in database") EOSplot(d, T.max = 600, T.plot = 600) title("Cp fit to 600 K, plot to 600 K") EOSplot(d, coefficients = CH4coeffs, T.plot = 600) title("Cp from EOS parameters in database") par(opar) # Continuing from above, with user-defined variables Theta <- 228 # K invTTTheta3 <- function(T, P) (2*T) / (T-T*Theta) ^ 3 invTX <- function(T, P) 1 / T * water("XBorn", T = T, P = P)[,1] # Print the calculated values of invTTTheta3 EOSvar("invTTTheta3", d$T, d$P) # Use invTTTheta and invTX in a regression var <- c("invTTTheta3", "invTX") EOSregress(d, var) # Give them a "label" attribute for use in the legend attr(invTTTheta3, "label") <- quote(phantom()%*%2 * italic(T) / (italic(T) - italic(T) * Theta) ^ 3) attr(invTX, "label") <- quote(phantom() / italic(T * X)) # Uncomment the following to make the plot #EOSplot(d, var) ## Model experimental volumes of CH4 ## using HKF equation and an exploratory one f <- system.file("extdata/cpetc/HWM96_V.csv", package = "CHNOSZ") d <- read.csv(f) # Use data for CH4 near 280 bar d <- d[d$species == "CH4", ] d <- d[, -1] d <- d[abs(d$P - 28) < 0.1, ] d$P <- convert(d$P, "bar") # The HKF equation varHKF <- c("invTTheta", "QBorn") # alpha is the expansivity coefficient of water varal <- c("invTTheta", "alpha") opar <- par(mfrow = c(2, 2)) # For both HKF and the expansivity equation, # we'll fit up to a temperature limit EOSplot(d, varHKF, T.max = 663, T.plot = 625) legend("bottomright", pch = 1, legend = "Hnedkovsky et al., 1996") title("V of CH4(aq), HKF equation") EOSplot(d, varal, T.max = 663, T.plot = 625) title("V of CH4(aq), expansivity equation") EOSplot(d, varHKF, T.max = 663) title("V of CH4(aq), HKF equation") EOSplot(d, varal, T.max = 663) title("V of CH4(aq), expansivity equation") par(opar) # Note that the volume regression using the HKF gives # a result for omega (coefficient on Q) that is # not consistent with the high-T heat capacities
Calculate equilibrium chemical activities of species from the affinities of formation of the species at unit activity.
equilibrate(aout, balance = NULL, loga.balance = NULL, ispecies = !grepl("cr", aout$species$state), normalize = FALSE, as.residue = FALSE, method = c("boltzmann", "reaction"), tol = .Machine$double.eps^0.25) equil.boltzmann(Astar, n.balance, loga.balance) equil.reaction(Astar, n.balance, loga.balance, tol = .Machine$double.eps^0.25) moles(eout)
equilibrate(aout, balance = NULL, loga.balance = NULL, ispecies = !grepl("cr", aout$species$state), normalize = FALSE, as.residue = FALSE, method = c("boltzmann", "reaction"), tol = .Machine$double.eps^0.25) equil.boltzmann(Astar, n.balance, loga.balance) equil.reaction(Astar, n.balance, loga.balance, tol = .Machine$double.eps^0.25) moles(eout)
aout |
list, output from |
or mosaic
balance |
character or numeric, how to balance the transformations |
ispecies |
numeric, which species to include |
normalize |
logical, normalize the molar formulas of species by the balancing coefficients? |
as.residue |
logical, report results for the normalized formulas? |
Astar |
numeric, affinities of formation reactions excluding species contribution |
n.balance |
numeric, number of moles of balancing component in the formation reactions of the species of interest |
loga.balance |
numeric (single value or vector), logarithm of total activity of balanced quantity |
method |
character, equilibration method to use |
tol |
numeric, convergence tolerance for |
eout |
list, output from |
equilibrate
calculates the chemical activities of species in metastable equilibrium, for constant temperature, pressure and chemical activities of basis species, using specified balancing constraints on reactions between species.
It takes as input aout
, the output from affinity
, giving the chemical affinities of formation reaction of each species, which may be calculated on a multidimensional grid of conditions.
Alternatively, aout
can be the output from mosaic
, in which case the equilibrium activities of the formed species are calculated and combined with those of the changing basis species to make an object that can be plotted with diagram
.
The equilibrium chemical activities of species are calculated using either the equil.reaction
or equil.boltzmann
functions, the latter only if the balance is on one mole of species.
equilibrate
needs to be provided constraints on how to balance the reactions representing transformations between the species.
balance
indicates the balancing component, according to the following scheme:
‘NULL’: autoselect
name of basis species: balance on this basis species
‘length’: balance on length of proteins
‘1’: balance on one mole of species
numeric vector: user-defined constraints
The default value of NULL for balance
indicates to use the coefficients on the basis species that is present (i.e. with non-zero coefficients) in all formation reactions, or if that fails, to set the balance to ‘1’.
However, if all the species (as listed in code aout$species
) are proteins (have an underscore character in their names), the default value of NULL for balance
indicates to use ‘length’ as the balance.
NOTE: The summation of activities assumes an ideal system, so ‘molality’ is equivalent to ‘activity’ here.
loga.balance
gives the logarithm of the total activity of balance
(which is total activity of species for ‘1’ or total activity of amino acid residue-equivalents for ‘length’).
If loga.balance
is missing, its value is taken from the activities of species listed in aout
; this default is usually the desired operation.
The supplied value of loga.balance
may also be a vector of values, with length corresponding to the number of conditions in the calculations of affinity
.
normalize
if TRUE indicates to normalize the molar formulas of species by the balance coefficients.
This operation is intended for systems of proteins, whose conventional formulas are much larger than the basis speices.
The normalization also applies to the balancing coefficients, which as a result consist of ‘1’s.
After normalization and equilibration, the equilibrium activities are then re-scaled (for the original formulas of the species), unless as.residue
is TRUE.
equil.boltzmann
is used to calculate the equilibrium activities if balance
is ‘1’ (or when normalize
or as.residue
is TRUE), otherwise equil.reaction
is called.
The default behavior can be overriden by specifying either ‘boltzmann’ or ‘reaction’ in method
.
Using equil.reaction
may be needed for systems with huge (negative or positive) affinities, where equil.boltzmann
produces a NaN result.
ispecies
can be supplied to identify a subset of the species to include in the equilibrium calculation.
By default, this is all species except solids (species with ‘cr’ state).
However, the stability regions of solids are still calculated (by a call to diagram
without plotting).
At all points outside of their stability region, the logarithms of activities of solids are set to -999.
Likewise, where any solid species is calculated to be stable, the logarithms of activities of all aqueous species are set to -999.
moles
simply calculates the total number of moles of elements corresponding to the activities of formed species in the output from equilibrate
.
equil.reaction
and equil.boltzmann
each return a list with dimensions and length equal to those of Astar
, giving the log10
of the equilibrium activities of the species of interest.
equilibrate
returns a list, containing first the values in aout
, to which are appended m.balance
(the balancing coefficients if normalize
is TRUE, a vector of ‘1’s otherwise), n.balance
(the balancing coefficients if normalize
is FALSE, a vector of ‘1’s otherwise), loga.balance
, Astar
, and loga.equil
(the calculated equilibrium activities of the species).
The input values to equil.reaction
and equil.boltzmann
are in a list, Astar
, all elements of the list having the same dimensions; they can be vectors, matrices, or higher-dimensionsal arrays.
Each list element contains the chemical affinities of the formation reactions of one of the species of interest (in dimensionless base-10 units, i.e. A/2.303RT), calculated at unit activity of the species of interest.
The equilibrium base-10 logarithm activities of the species of interest returned by either function satisfy the constraints that 1) the final chemical affinities of the formation reactions of the species are all equal and 2) the total activity of the balancing component is equal to (loga.balance
).
The first constraint does not impose a complete equilibrium, where the affinities of the formation reactions are all equal to zero, but allows for a metastable equilibrium, where the affinities of the formation reactions are equal to each other.
In equil.reaction
(the algorithm described in Dick, 2008 and the only one available prior to CHNOSZ_0.8), the calculations of relative abundances of species are based on a solving a system of equations representing the two constraints stated above.
The solution is found using uniroot
with a flexible method for generating initial guesses.
In equil.boltzmann
, the chemical activities of species are calculated using the Boltzmann distribution.
This calculation is faster than the algorithm of equil.reaction
, but is limited to systems where the transformations are all balanced on one mole of species.
If equil.boltzmann
is called with balance
other than ‘1’, it stops with an error.
Despite its name, this function does not generally produce a complete equilibrium.
It returns activities of species such that the affinities of formation reactions are equal to each other (and transformations between species have zero affinity); this is a type of metastable equilibrium.
Although they are equal to each other, the affinities are not necessarily equal to zero.
Use solubility
to find complete equilibrium, where the affinities of the formation reactions become zero.
Dick, J. M. (2008) Calculation of the relative metastabilities of proteins using the CHNOSZ software package. Geochem. Trans. 9:10. doi:10.1186/1467-4866-9-10
diagram
has examples of using equilibrate
to make equilibrium activity diagrams.
palply
is used by both equil.reaction
and equil.boltzmann
to parallelize intensive parts of the calculations.
See the vignette multi-metal for an example of balancing on two elements (N in the basis species, C in the formed species).
## Equilibrium in a simple system: ## ionization of carbonic acid basis("CHNOS+") species(c("CO2", "HCO3-", "CO3-2")) # Set unit activity of the species (0 = log10(1)) species(1:3, 0) # Calculate Astar (for unit activity) res <- 100 Astar <- affinity(pH = c(0, 14, res))$values # The logarithms of activity for a total activity # of the balancing component (CO2) equal to 0.001 loga.boltz <- equil.boltzmann(Astar, c(1, 1, 1), 0.001) # Calculated another way loga.react <- equil.reaction(Astar, c(1, 1, 1), rep(0.001, 100)) # They should be pretty close stopifnot(all.equal(loga.boltz, loga.react)) # The first ionization constant (pKa) ipKa <- which.min(abs(loga.boltz[[1]] - loga.boltz[[2]])) pKa.equil <- seq(0, 14, length.out = res)[ipKa] # Calculate logK directly logK <- subcrt(c("CO2","H2O","HCO3-","H+"), c(-1, -1, 1, 1), T = 25)$out$logK # We could decrease tolerance here by increasing res stopifnot(all.equal(pKa.equil, -logK, tolerance = 1e-2))
## Equilibrium in a simple system: ## ionization of carbonic acid basis("CHNOS+") species(c("CO2", "HCO3-", "CO3-2")) # Set unit activity of the species (0 = log10(1)) species(1:3, 0) # Calculate Astar (for unit activity) res <- 100 Astar <- affinity(pH = c(0, 14, res))$values # The logarithms of activity for a total activity # of the balancing component (CO2) equal to 0.001 loga.boltz <- equil.boltzmann(Astar, c(1, 1, 1), 0.001) # Calculated another way loga.react <- equil.reaction(Astar, c(1, 1, 1), rep(0.001, 100)) # They should be pretty close stopifnot(all.equal(loga.boltz, loga.react)) # The first ionization constant (pKa) ipKa <- which.min(abs(loga.boltz[[1]] - loga.boltz[[2]])) pKa.equil <- seq(0, 14, length.out = res)[ipKa] # Calculate logK directly logK <- subcrt(c("CO2","H2O","HCO3-","H+"), c(-1, -1, 1, 1), T = 25)$out$logK # We could decrease tolerance here by increasing res stopifnot(all.equal(pKa.equil, -logK, tolerance = 1e-2))
Run the examples contained in each of the documentation topics.
examples(save.png = FALSE) demos(which = c("sources", "protein.equil", "affinity", "NaCl", "density", "ORP", "ionize", "buffer", "protbuff", "glycinate", "mosaic", "copper", "arsenic", "solubility", "gold", "contour", "sphalerite", "minsol", "Shh", "saturation", "adenine", "DEW", "lambda", "potassium", "TCA", "aluminum", "AD", "comproportionation", "Pourbaix", "E_coli", "yttrium", "rank.affinity"), save.png = FALSE)
examples(save.png = FALSE) demos(which = c("sources", "protein.equil", "affinity", "NaCl", "density", "ORP", "ionize", "buffer", "protbuff", "glycinate", "mosaic", "copper", "arsenic", "solubility", "gold", "contour", "sphalerite", "minsol", "Shh", "saturation", "adenine", "DEW", "lambda", "potassium", "TCA", "aluminum", "AD", "comproportionation", "Pourbaix", "E_coli", "yttrium", "rank.affinity"), save.png = FALSE)
save.png |
logical, generate PNG image files for the plots? |
which |
character, which example to run |
examples
runs all the examples in the help pages for the package.
example
is called for each topic with ask
set to FALSE
(so all of the figures are shown without prompting the user).
demos
runs all the demos
in the package.
The demo(s) to run is/are specified by which
; the default is to run them in the order of the list below.
Cross-check the reference list with the thermodynamic database
Chemical activities of two proteins in metastable equilibrium (Dick and Shock, 2011)
Affinities of metabolic reactions and amino acid synthesis (Amend and Shock, 1998, 2001)
Equilibrium constant for aqueous NaCl dissociation (Shock et al., 1992)
Density of H2O, inverted from IAPWS-95 equations (rho.IAPWS95
)
Temperature dependence of oxidation-reduction potential for redox standards
ionize.aa(): contour plots of net charge and ionization properties of LYSC_CHICK
Minerals and aqueous species as buffers of hydrogen fugacity (Schulte and Shock, 1995)
Chemical activities buffered by thiol peroxidases or sigma factors
Metal-glycinate complexes (Shock and Koretsky, 1995; Azadi et al., 2019)
Eh-pH diagram with two sets of changing basis species (Garrels and Christ, 1965)
Another example of mosaic
: complexation of Cu with glycine (Aksu and Doyle, 2001)
Another example of mosaic
: Eh-pH diagram for the system As-O-H-S (Lu and Zhu, 2011)
Solubility of calcite (cf. Manning et al., 2013) and CO2 (cf. Stumm and Morgan, 1996)
Solubility of gold (Akinfiev and Zotov; 2001; Stefánsson and Seward, 2004; Williams-Jones et al., 2009)
Gold solubility contours on a log fO2 - pH diagram (Williams-Jones et al., 2009)
Solubility of sphalerite (Akinfiev and Tagirov, 2014)
Solubilities of multiple minerals
of dehydration reactions; SVG file contains tooltips and links
Affinities of transcription factors relative to Sonic hedgehog (Dick, 2015)
Equilibrium activity diagram showing activity ratios and mineral saturation limits (Bowers et al., 1984)
HKF regression of heat capacity and volume of aqueous adenine (Lowe et al., 2017)
Deep Earth Water (DEW) model for high pressures (Sverjensky et al., 2014a and 2014b)
Effects of lambda transition on thermodynamic properties of quartz (Berman, 1988)
Comparison of thermodynamic datasets for predicting mineral stabilities (Sverjensky et al., 1991)
Standard Gibbs energies of the tricarboxylic (citric) acid cycle (Canovas and Shock, 2016)
Reactions involving Al-bearing minerals (Zimmer et al., 2016; Tutolo et al., 2014)
Rank abundance distribution for RuBisCO and acetyl-CoA carboxylase
Dissolved gases: Henry's constant, volume, and heat capacity (Akinfiev and Diamond, 2003)
Gibbs energy of sulfur comproportionation (Amend et al., 2020)
Eh-pH diagram for Fe-O-H with equisolubility lines (Pourbaix, 1974)
Gibbs energy of biomass synthesis in E. coli (LaRowe and Amend, 2016)
Affinity ranking for proteins in yeast nutrient limitation (data from Tai et al., 2005)
logB.to.OBIGT
fits at 800 and 1000 bar and Y speciation in NaCl
solution at varying pH (Guan et al., 2020)
For either function, if save.png
is TRUE, the plots are saved in png
files whose names begin with the names of the help topics or demos.
Two of the demos have external dependencies and are not automatically run by demos
.
‘dehydration’ creates an interactive SVG file; this demo depends on RSVGTipsDevice, which is not available for Windows.
‘carboxylase’ creates an animated GIF; this demo requires that the ImageMagick convert
commmand be available on the system (tested on Linux and Windows).
‘carboxylase’ animates diagrams showing rankings of calculated chemical activities along a combined T and logaH2 gradient, or makes a single plot on the default device (without conversion to animated GIF) if a single temperature (T
) is specified in the code.
To run this demo, an empty directory named ‘png’ must be present (as a subdirectory of the R working directory).
The proteins in the calculation are 24 carboxylases from a variety of organisms.
There are 12 ribulose phosphate carboxylase and 12 acetyl-coenzyme A carboxylase; 6 of each type are from nominally mesophilic organisms and 6 from nominally thermophilic organisms, shown as blue and red symbols on the diagrams.
The activities of hydrogen at each temperature are calculated using ; this equation comes from a model of relative stabilities of proteins in a hot-spring environment (Dick and Shock, 2011).
The discontinuities apparent in the plot made by the NaCl
demo illustrate limitations of the "g function" for charged species in the revised HKF model (the 355 °C boundary of region II in Figure 6 of Shock et al., 1992).
Note that SUPCRT92 (Johnson et al., 1992) gives similar output at 500 bar.
However, SUPCRT does not output thermodynamic properties above 350 °C at PSAT; see Warning in subcrt
.
Akinfiev, N. N. and Diamond, L. W. (2003) Thermodynamic description of aqueous nonelectrolytes at infinite dilution over a wide range of state parameters. Geochim. Cosmochim. Acta 67, 613–629. doi:10.1016/S0016-7037(02)01141-9
Akinfiev, N. N. and Tagirov, B. R. (2014) Zn in hydrothermal systems: Thermodynamic description of hydroxide, chloride, and hydrosulfide complexes. Geochem. Int. 52, 197–214. doi:10.1134/S0016702914030021
Akinfiev, N. N. and Zotov, A. V. (2001) Thermodynamic description of chloride, hydrosulfide, and hydroxo complexes of Ag(I), Cu(I), and Au(I) at temperatures of 25-500°C and pressures of 1-2000 bar. Geochem. Int. 39, 990–1006.
Aksu, S. and Doyle, F. M. (2001) Electrochemistry of copper in aqueous glycine solutions. J. Electrochem. Soc. 148, B51–B57.
Amend, J. P. and Shock, E. L. (1998) Energetics of amino acid synthesis in hydrothermal ecosystems. Science 281, 1659–1662. doi:10.1126/science.281.5383.1659
Amend, J. P. and Shock, E. L. (2001) Energetics of overall metabolic reactions of thermophilic and hyperthermophilic Archaea and Bacteria. FEMS Microbiol. Rev. 25, 175–243. doi:10.1016/S0168-6445(00)00062-0
Amend, J. P., Aronson, H. S., Macalady, J. and LaRowe, D. E. (2020) Another chemolithotrophic metabolism missing in nature: sulfur comproportionation. Environ. Microbiol. 22, 1971–1976. doi:10.1111/1462-2920.14982
Azadi, M. R., Karrech, A., Attar, M. and Elchalakani, M. (2019) Data analysis and estimation of thermodynamic properties of aqueous monovalent metal-glycinate complexes. Fluid Phase Equilib. 480, 25-40. doi:10.1016/j.fluid.2018.10.002
Berman, R. G. (1988) Internally-consistent thermodynamic data for minerals in the system Na2O-K2O-CaO-MgO-FeO-Fe2O3-Al2O3-SiO2-TiO2-H2O-CO2. J. Petrol. 29, 445-522. doi:10.1093/petrology/29.2.445
Bowers, T. S., Jackson, K. J. and Helgeson, H. C. (1984) Equilibrium Activity Diagrams for Coexisting Minerals and Aqueous Solutions at Pressures and Temperatures to 5 kb and 600°C, Springer-Verlag, Berlin, 397 p. https://www.worldcat.org/oclc/11133620
Canovas, P. A., III and Shock, E. L. (2016) Geobiochemistry of metabolism: Standard state thermodynamic properties of the citric acid cycle. Geochim. Cosmochim. Acta 195, 293–322. doi:10.1016/j.gca.2016.08.028
Dick, J. M. and Shock, E. L. (2011) Calculation of the relative chemical stabilities of proteins as a function of temperature and redox chemistry in a hot spring. PLOS One 6, e22782. doi:10.1371/journal.pone.0022782
Dick, J. M. (2015) Chemical integration of proteins in signaling and development. bioRxiv. doi:10.1101/015826
Garrels, R. M. and Christ, C. L. (1965) Solutions, Minerals, and Equilibria, Harper & Row, New York, 450 p. https://www.worldcat.org/oclc/517586
Guan, Q., Mei, Y., Etschmann, B., Testemale, D., Louvel, M. and Brugger, J. (2020) Yttrium complexation and hydration in chloride-rich hydrothermal fluids: A combined ab initio molecular dynamics and in situ X-ray absorption spectroscopy study. Geochim. Cosmochim. Acta 281, 168–189. doi:10.1016/j.gca.2020.04.015
Johnson, J. W., Oelkers, E. H. and Helgeson, H. C. (1992) SUPCRT92: A software package for calculating the standard molal thermodynamic properties of minerals, gases, aqueous species, and reactions from 1 to 5000 bar and 0 to 1000°C. Comp. Geosci. 18, 899–947. doi:10.1016/0098-3004(92)90029-Q
LaRowe, D. E. and Amend, J. P. (2016) The energetics of anabolism in natural settings. ISME J. 10, 1285–1295. doi:10.1038/ismej.2015.227
Lowe, A. R., Cox, J. S. and Tremaine, P. R. (2017) Thermodynamics of aqueous adenine: Standard partial molar volumes and heat capacities of adenine, adeninium chloride, and sodium adeninate from T = 278.15 K to 393.15 K. J. Chem. Thermodyn. 112, 129–145. doi:10.1016/j.jct.2017.04.005
Lu, P. and Zhu, C. (2011) Arsenic Eh–pH diagrams at 25°C and 1 bar. Environ. Earth Sci. 62, 1673–1683. doi:10.1007/s12665-010-0652-x
Manning, C. E., Shock, E. L. and Sverjensky, D. A. (2013) The chemistry of carbon in aqueous fluids at crustal and upper-mantle conditions: Experimental and theoretical constraints. Rev. Mineral. Geochem. 75, 109–148. doi:10.2138/rmg.2013.75.5
Pourbaix, M. (1974) Atlas of Electrochemical Equilibria in Aqueous Solutions, NACE, Houston, TX and CEBELCOR, Brussels. https://www.worldcat.org/oclc/563921897
Schulte, M. D. and Shock, E. L. (1995) Thermodynamics of Strecker synthesis in hydrothermal systems. Orig. Life Evol. Biosph. 25, 161–173. doi:10.1007/BF01581580
Shock, E. L. and Koretsky, C. M. (1995) Metal-organic complexes in geochemical processes: Estimation of standard partial molal thermodynamic properties of aqueous complexes between metal cations and monovalent organic acid ligands at high pressures and temperatures. Geochim. Cosmochim. Acta 59, 1497–1532. doi:10.1016/0016-7037(95)00058-8
Shock, E. L., Oelkers, E. H., Johnson, J. W., Sverjensky, D. A. and Helgeson, H. C. (1992) Calculation of the thermodynamic properties of aqueous species at high pressures and temperatures: Effective electrostatic radii, dissociation constants and standard partial molal properties to 1000 °C and 5 kbar. J. Chem. Soc. Faraday Trans. 88, 803–826. doi:10.1039/FT9928800803
Stefánsson, A. and Seward, T. M. (2004) Gold(I) complexing in aqueous sulphide solutions to 500°C at 500 bar. Geochim. Cosmochim. Acta 68, 4121–4143. doi:10.1016/j.gca.2004.04.006
Stumm, W. and Morgan, J. J. (1996) Aquatic Chemistry: Chemical Equilibria and Rates in Natural Waters, John Wiley & Sons, New York, 1040 p. https://www.worldcat.org/oclc/31754493
Sverjensky, D. A., Harrison, B. and Azzolini, D. (2014a) Water in the deep Earth: The dielectric constant and the solubilities of quartz and corundum to 60 kb and 1,200 °C. Geochim. Cosmochim. Acta 129, 125–145. doi:10.1016/j.gca.2013.12.019
Sverjensky, D. A., Hemley, J. J. and D'Angelo, W. M. (1991) Thermodynamic assessment of hydrothermal alkali feldspar-mica-aluminosilicate equilibria. Geochim. Cosmochim. Acta 55, 989-1004. doi:10.1016/0016-7037(91)90157-Z
Sverjensky, D. A., Stagno, V. and Huang, F. (2014b) Important role for organic carbon in subduction-zone fluids in the deep carbon cycle. Nat. Geosci. 7, 909–913. doi:10.1038/ngeo2291
Tai, S. L., Boer, V. M., Daran-Lapujade, P., Walsh, M. C., de Winde, J. H., Daran, J.-M. and Pronk, J. T. (2005) Two-dimensional transcriptome analysis in chemostat cultures: Combinatorial effects of oxygen availability and macronutrient limitation in Saccharomyces cerevisiae. J. Biol. Chem. 280, 437–447. doi:10.1074/jbc.M410573200
Tutolo, B. M., Kong, X.-Z., Seyfried, W. E., Jr. and Saar, M. O. (2014) Internal consistency in aqueous geochemical data revisited: Applications to the aluminum system. Geochim. Cosmochim. Acta 133, 216–234. doi:10.1016/j.gca.2014.02.036
Williams-Jones, A. E., Bowell, R. J. and Migdisov, A. A. (2009) Gold in solution. Elements 5, 281–287. doi:10.2113/gselements.5.5.281
Zimmer, K., Zhang, Y., Lu, P., Chen, Y., Zhang, G., Dalkilic, M. and Zhu, C. (2016) SUPCRTBL: A revised and extended thermodynamic dataset and software package of SUPCRT92. Comp. Geosci. 90, 97–111. doi:10.1016/j.cageo.2016.02.013
demos(c("ORP", "NaCl"))
demos(c("ORP", "NaCl"))
The files in the subdirectories of extdata
provide additional thermodynamic data and other data to support the examples in the package documentation and vignettes.
See thermo
for a description of the files in extdata/OBIGT
, which are used to generate the thermodynamic database.
Files in Berman
contain thermodynamic data for minerals using the Berman formulation:
Ber88_1988.csv
contains thermodynamic data for minerals taken from Berman (1988).
Other files with names like xxx_yyyy.csv
contain thermodynamic data from other sources; xxx in the filename corresponds to the reference in thermo$OBIGT
and yyyy gives the year of publication.
Berman
uses these data for the calculation of thermodynamic properties at specified P and T, which are then available for use in subcrt
.
If there are any duplicated mineral names in the files, only the most recent data are used, as determined by the year in the file name.
Following conventions used SUPCRT92 (see Helgeson et al., 1978), the names of sanidine and microcline were changed to K-feldspar,high and K-feldspar,low (by using the same names in all data files, loading the optional SUPCRT92 data file updates these minerals rather than makes new ones).
sympy.R
is an R script that uses rSymPy to symbolically integrate Bermans's equations for heat capacity and volume to write experessions for enthalpy, entropy and Gibbs energy.
The testing
directory contains data files based on Berman and Aranovich (1996). These are used to demonstrate the addition of data from a user-supplied file (see Berman
).
Files in cpetc
contain experimental and calculated thermodynamic and environmental data:
PM90.csv
Heat capacities of four unfolded aqueous proteins taken from Privalov and Makhatadze, 1990. Temperature in °C is in the first column, and heat capacities of the proteins in J mol K
in the remaining columns. See
ionize.aa
and the vignette anintro for examples that use this file.
RH95.csv
Heat capacity data for iron taken from Robie and Hemingway, 1995. Temperature in Kelvin is in the first column, heat capacity in J K mol
in the second. See
subcrt
for an example that uses this file.
SOJSH.csv
Experimental equilibrium constants for the reaction NaCl(aq) = Na+ + Cl- as a function of temperature and pressure taken from Fig. 1 of Shock et al., 1992. See demo("NaCl")
for an example that uses this file.
HWM96_V.csv
, HW97_Cp.csv
Apparent molar volumes and heat capacities of CH4, CO2, H2S, and NH3 in dilute aqueous solutions reported by Hnědkovský et al., 1996 and Hnědkovský and Wood, 1997. Units are Kelvin, MPa, J/K/mol, and cm3/mol. See demo("AD")
, EOSregress
and the vignette eos-regress for examples that use these files.
SC10_Rainbow.csv
Values of temperature (°C), pH and logarithms of activity of CO2, H2, NH4+, H2S and CH4 for mixing of seawater and hydrothermal fluid at Rainbow field (Mid-Atlantic Ridge), taken from Shock and Canovas, 2010. See the vignette anintro for an example that uses this file.
SS98_Fig5a.csv
, SS98_Fig5b.csv
Values of logarithm of fugacity of O2 and pH as a function of temperature for mixing of seawater and hydrothermal fluid, digitized from Figs. 5a and b of Shock and Schulte, 1998. See the vignette anintro for an example that uses this file.
rubisco.csv
UniProt IDs for Rubisco, ranges of optimal growth temperature of organisms, domain and name of organisms, and URL of reference for growth temperature, from Dick, 2014. See rank.affinity
and the vignette anintro for examples that use this file.
bluered.txt
Blue - light grey - red color palette, computed using colorspace::diverge_hcl(1000,
c = 100, l = c(50, 90), power = 1)
. This is used by ZC.col
.
AD03_Fig1?.csv
Experimental data points digitized from Figure 1 of Akinfiev and Diamond, 2003, used in demo("AD")
.
TKSS14_Fig2.csv
Experimental data points digitized from Figure 2 of Tutolo et al., 2014, used in demo("aluminum")
.
Mer75_Table4.csv
Values of log(aK+/aH+) and log(aNa+/aH+) from Table 4 of Merino, 1975, used in demo("aluminum")
.
Files in protein
contain protein sequences and amino acid compositions for proteins.
rubisco.fasta
Sequences of Rubisco obtained from UniProt (see Dick, 2014). See the vignette anintro for an example that uses this file.
POLG.csv
Amino acid compositions of a few proteins used for some tests and examples.
These are various subunits of the Poliovirus type 1 polyprotein (POLG_POL1M in UniProt).
TBD+05.csv
lists genes with transcriptomic expression changes in carbon limitation stress response experiments in yeast (Tai et al., 2005).
TBD+05_aa.csv
has the amino acid compositions of proteins coded by those genes.
The last two files are used in demo{"rank.affinity"}
.
Files in taxonomy
contain taxonomic data files:
names.dmp
and nodes.dmp
are excerpts of NCBI taxonomy files (https://ftp.ncbi.nih.gov/pub/taxonomy/taxdump.tar.gz, accessed 2010-02-15). These files contain only the entries for Escherichia coli K-12, Saccharomyces cerevisiae, Homo sapiens, Pyrococcus furisosus and Methanocaldococcus jannaschii (taxids 83333, 4932, 9606, 186497, 243232) and the higher-ranking nodes (genus, family, etc.) in the respective lineages. See taxonomy
for examples that use these files.
Files in adds
contain additional thermodynamic data and group additivity definitions:
BZA10.csv
contains supplementary thermodynamic data taken from Bazarkina et al. (2010). The data can be added to the database in the current session using add.OBIGT
. See add.OBIGT
for an example that uses this file.
OBIGT_check.csv
contains the results of running check.OBIGT
to check the internal consistency of entries in the default and optional datafiles.
RH98_Table15.csv
Group stoichiometries for high molecular weight crystalline and liquid organic compounds taken from Table 15 of Richard and Helgeson, 1998. The first three columns have the compound
name, formula
and physical state
(‘cr’ or ‘liq’). The remaining columns have the numbers of each group in the compound; the names of the groups (columns) correspond to species in thermo$OBIGT
. The compound named ‘5a(H),14a(H)-cholestane’ in the paper has been changed to ‘5a(H),14b(H)-cholestane’ here to match the group stoichiometry given in the table. See RH2OBIGT
for a function that uses this file.
SK95.csv
contains thermodynamic data for alanate, glycinate, and their complexes with metals, taken from Amend and Helgeson (1997) and Shock and Koretsky (1995) as corrected in slop98.dat. These data are used in demo("copper")
and demo("glycinate")
.
LA19_test.csv
contains thermodynamic data for dimethylamine and trimethylamine from LaRowe and Amend (2019) in energy units of both J and cal. This file is used in test-util.data.R
) to check the messages produced by check.GHS
and check.EOS
.
Akinfiev, N. N. and Diamond, L. W. (2003) Thermodynamic description of aqueous nonelectrolytes at infinite dilution over a wide range of state parameters. Geochim. Cosmochim. Acta 67, 613–629. doi:10.1016/S0016-7037(02)01141-9
Amend, J. P. and Helgeson, H. C. (1997) Calculation of the standard molal thermodynamic properties of aqueous biomolecules at elevated temperatures and pressures. Part 1. L-α-amino acids. J. Chem. Soc., Faraday Trans. 93, 1927–1941. doi:10.1039/A608126F
Bazarkina, E. F., Zotov, A. V. and Akinfiev, N. N. (2010) Pressure-dependent stability of cadmium chloride complexes: Potentiometric measurements at 1–1000 bar and 25°C. Geol. Ore Deposits 52, 167–178. doi:10.1134/S1075701510020054
Berman, R. G. (1988) Internally-consistent thermodynamic data for minerals in the system Na2O-K2O-CaO-MgO-FeO-Fe2O3-Al2O3-SiO2-TiO2-H2O-CO2. J. Petrol. 29, 445-522. doi:10.1093/petrology/29.2.445
Berman, R. G. and Aranovich, L. Ya. (1996) Optimized standard state and solution properties of minerals. I. Model calibration for olivine, orthopyroxene, cordierite, garnet, and ilmenite in the system FeO-MgO-CaO-Al2O3-TiO2-SiO2. Contrib. Mineral. Petrol. 126, 1-24. doi:10.1007/s004100050233
Dick, J. M. (2014) Average oxidation state of carbon in proteins. J. R. Soc. Interface 11, 20131095. doi:10.1098/rsif.2013.1095
Gattiker, A., Michoud, K., Rivoire, C., Auchincloss, A. H., Coudert, E., Lima, T., Kersey, P., Pagni, M., Sigrist, C. J. A., Lachaize, C., Veuthey, A.-L., Gasteiger, E. and Bairoch, A. (2003) Automatic annotation of microbial proteomes in Swiss-Prot. Comput. Biol. Chem. 27, 49–58. doi:10.1016/S1476-9271(02)00094-4
Helgeson, H. C., Delany, J. M., Nesbitt, H. W. and Bird, D. K. (1978) Summary and critique of the thermodynamic properties of rock-forming minerals. Am. J. Sci. 278-A, 1–229. https://www.worldcat.org/oclc/13594862
Hnědkovský, L., Wood, R. H. and Majer, V. (1996) Volumes of aqueous solutions of CH4, CO2, H2S, and NH3 at temperatures from 298.15 K to 705 K and pressures to 35 MPa. J. Chem. Thermodyn. 28, 125–142. doi:10.1006/jcht.1996.0011
Hnědkovský, L. and Wood, R. H. (1997) Apparent molar heat capacities of aqueous solutions of CH4, CO2, H2S, and NH3 at temperatures from 304 K to 704 K at a pressure of 28 MPa. J. Chem. Thermodyn. 29, 731–747. doi:10.1006/jcht.1997.0192
Joint Genome Institute (2007) Bison Pool Environmental Genome. Protein sequence files downloaded from IMG/M (https://img.jgi.doe.gov/)
LaRowe, D. E. and Amend, J. P. (2019) The energetics of fermentation in natural settings. Geomicrobiol. J. 36, 492–505. doi:10.1080/01490451.2019.1573278
Merino, E. (1975) Diagenesis in teriary sandstones from Kettleman North Dome, California. II. Interstitial solutions: distribution of aqueous species at 100°C and chemical relation to diagenetic mineralogy. Geochim. Cosmochim. Acta 39, 1629–1645. doi:10.1016/0016-7037(75)90085-X
Privalov, P. L. and Makhatadze, G. I. (1990) Heat capacity of proteins. II. Partial molar heat capacity of the unfolded polypeptide chain of proteins: Protein unfolding effects. J. Mol. Biol. 213, 385–391. doi:10.1016/S0022-2836(05)80198-6
Richard, L. and Helgeson, H. C. (1998) Calculation of the thermodynamic properties at elevated temperatures and pressures of saturated and aromatic high molecular weight solid and liquid hydrocarbons in kerogen, bitumen, petroleum, and other organic matter of biogeochemical interest. Geochim. Cosmochim. Acta 62, 3591–3636. doi:10.1016/S0016-7037(97)00345-1
Robie, R. A. and Hemingway, B. S. (1995) Thermodynamic Properties of Minerals and Related Substances at 298.15 K and 1 Bar ( Pascals) Pressure and at Higher Temperatures. U. S. Geol. Surv., Bull. 2131, 461 p. https://www.worldcat.org/oclc/32590140
Shock, E. and Canovas, P. (2010) The potential for abiotic organic synthesis and biosynthesis at seafloor hydrothermal systems. Geofluids 10, 161–192. doi:10.1111/j.1468-8123.2010.00277.x
Shock, E. L. and Koretsky, C. M. (1995) Metal-organic complexes in geochemical processes: Estimation of standard partial molal thermodynamic properties of aqueous complexes between metal cations and monovalent organic acid ligands at high pressures and temperatures. Geochim. Cosmochim. Acta 59, 1497–1532. doi:10.1016/0016-7037(95)00058-8
Shock, E. L., Oelkers, E. H., Johnson, J. W., Sverjensky, D. A. and Helgeson, H. C. (1992) Calculation of the thermodynamic properties of aqueous species at high pressures and temperatures: Effective electrostatic radii, dissociation constants and standard partial molal properties to 1000 °C and 5 kbar. J. Chem. Soc. Faraday Trans. 88, 803–826. doi:10.1039/FT9928800803
Shock, E. L. and Schulte, M. D. (1998) Organic synthesis during fluid mixing in hydrothermal systems. J. Geophys. Res. 103, 28513–28527. doi:10.1029/98JE02142
Tai, S. L., Boer, V. M., Daran-Lapujade, P., Walsh, M. C., de Winde, J. H., Daran, J.-M. and Pronk, J. T. (2005) Two-dimensional transcriptome analysis in chemostat cultures: Combinatorial effects of oxygen availability and macronutrient limitation in Saccharomyces cerevisiae. J. Biol. Chem. 280, 437–447. doi:10.1074/jbc.M410573200
Tutolo, B. M., Kong, X.-Z., Seyfried, W. E., Jr. and Saar, M. O. (2014) Internal consistency in aqueous geochemical data revisited: Applications to the aluminum system. Geochim. Cosmochim. Acta 133, 216–234. doi:10.1016/j.gca.2014.02.036
Calculate thermodynamic properties of water following the IAPWS-95 formulation.
IAPWS95(property, T = 298.15, rho = 1000)
IAPWS95(property, T = 298.15, rho = 1000)
property |
character, name(s) of property(s) to calculate |
T |
numeric, temperature (K) |
rho |
numeric, density (kg m |
IAPWS95
provides an implementation of the IAPWS-95 formulation for properties (including pressure) calculated as a function of temperature and density.
The IAPWS95
function returns values of thermodynamic properties in specific units (per gram).
The IAPWS-95 formulation follows the triple point convention used in engineering (values of internal energy and entropy are taken to be zero at the triple point).
For IAPWS95
the upper temperature limit of validity is 1000 °C, but extrapolation to much higher temperatures is possible (Wagner and Pruss, 2002).
Valid pressures are from the greater of zero bar or the melting pressure at temperature to 10000 bar (with the provision for extrapolation to more extreme conditions).
The function does not check these limits and will attempt calculations for any range of input parameters, but may return NA
for properties that fail to be calculated at given temperatures and pressures and/or produce warnings or even errors when problems are encountered.
A data frame the number of rows of which corresponds to the number of input temperature, pressure and/or density values.
Wagner, W. and Pruss, A. (2002) The IAPWS formulation 1995 for the thermodynamic properties of ordinary water substance for general and scientific use. J. Phys. Chem. Ref. Data 31, 387–535. doi:10.1063/1.1461829
util.water
for properties along the saturation curve (WP02.auxiliary
) and calculation of density from pressure and temperature (rho.IAPWS92
).
water.IAPWS95
is a wrapper around IAPWS95
and the utility functions, which converts the specific units to molar quantities, and is used in higher-level functions (water
).
# Calculate pressure for given temperature and density IAPWS95("P", T = 500, rho = 838.0235)
# Calculate pressure for given temperature and density IAPWS95("P", T = 500, rho = 838.0235)
Search for species by name or formula, retrieve their thermodynamic properties and parameters, and add proteins to the thermodynamic database.
info(species = NULL, state = NULL, check.it=TRUE)
info(species = NULL, state = NULL, check.it=TRUE)
species |
character, names or formulas of species, or (for |
state |
character, physical states of the species |
check.it |
logical, check GHS and EOS parameters for self-consistency? |
info
is the primary function used for querying the thermodynamic database (thermo()$OBIGT
).
It is often called recursively; first with a character value (or values) for species
indicating the name(s) or formula(s) of the species of interest.
The result of this call is a numeric value, which can be provided as an argument in a second call to info
in order to retrieve a data frame of the thermodynamic properties of the species.
The text of species
is searched in the names, chemical formulas, and abbreviations (in the ‘abbrv’ column) in the thermodynamic database.
If the text of the species
is matched, the index of that species is returned.
If there are multiple matches for the species
, and state
is NULL, the index of first match is returned.
The order of entries in the database is grouped by states in the order ‘aq’, ‘cr’, ‘gas’, ‘liq’.
Therefore, for substances represented by both aqueous and gaseous species, the index of the aqueous species is returned, unless state
is set to ‘gas’.
Note that names (not formulas) of inorganic species, such as ‘oxygen’ and ‘methane’, are used only for the gas.
Names of species including an underscore character are indicative of proteins, e.g. ‘LYSC_CHICK’.
If the name of a protein is provided to info
and the composition of the protein can be found using pinfo
, the thermodyamic properties and parameters of the nonionized protein (calculated using amino acid group additivity) are added to the thermodynamic database.
Included in the return value, as for other species, is the index of the protein in the thermodynamic database or NA
if the protein is not found. Names of proteins and other species can be mixed.
If no exact matches are found, info
searches the database for similar names or formulas using agrep
.
If any of these are found, the results are summarized on the screen, but the function always returns NA in this case.
With a numeric argument, the rows of thermo()$OBIGT
indicated by ispecies
are returned, after removing any order-of-magnitude scaling factors (see thermo
).
If these species are all aqueous or are all not aqueous, the compounded column names used in thermo()$OBIGT
are replaced with names appropriate for the corresponding equations of state.
A missing value of one of the standard molal Gibbs energy (G
) or enthalpy (H
) of formation from the elements or entropy (S
) is calculated from the other two, if available.
If check.it
is TRUE, several checks of self consistency among the thermodynamic properties and parameters are performed using check.GHS
and check.EOS
.
retrieve
for searching species by element; check.OBIGT
for checking self-consistency of each species.
## Summary of available data info() ## Species information # Search for something named (or whose formula is) "Fe" si <- info("Fe") # Use the number to get the full entry info(si) # Show data for the higher-temperature phases info(si:(si+3)) ## Dealing with states # Order of precedence for names: # aq > cr > gas > liq info(c("ethanol", "adenosine")) # aq, aq # State argument overrides the default info(c("ethanol", "adenosine"), state = c("gas", "cr")) # Exceptions: gases have precedence for names of methane and inorganic gases info(c("methane", "oxygen")) # gas, gas # Formulas default to aqueous species, if available i1 <- info(c("CH4", "CO2", "CS2", "MgO")) info(i1)$state # aq, aq, gas, cr # State argument overrides the default i2 <- info(c("CH4", "CO2", "MgO"), "gas") info(i2)$state # gas, gas, NA ## Partial name or formula searches info("ATP") info("thiol") info("MgC") # Add an extra character to refine a search # or to search using terms that have exact matches info("MgC ") info("acetate ") info(" H2O")
## Summary of available data info() ## Species information # Search for something named (or whose formula is) "Fe" si <- info("Fe") # Use the number to get the full entry info(si) # Show data for the higher-temperature phases info(si:(si+3)) ## Dealing with states # Order of precedence for names: # aq > cr > gas > liq info(c("ethanol", "adenosine")) # aq, aq # State argument overrides the default info(c("ethanol", "adenosine"), state = c("gas", "cr")) # Exceptions: gases have precedence for names of methane and inorganic gases info(c("methane", "oxygen")) # gas, gas # Formulas default to aqueous species, if available i1 <- info(c("CH4", "CO2", "CS2", "MgO")) info(i1)$state # aq, aq, gas, cr # State argument overrides the default i2 <- info(c("CH4", "CO2", "MgO"), "gas") info(i2)$state # gas, gas, NA ## Partial name or formula searches info("ATP") info("thiol") info("MgC") # Add an extra character to refine a search # or to search using terms that have exact matches info("MgC ") info("acetate ") info(" H2O")
Calculate the charges of proteins and contributions of ionization to the thermodynamic properties of proteins.
ionize.aa(aa, property = "Z", T = 25, P = "Psat", pH = 7, ret.val = NULL, suppress.Cys = FALSE)
ionize.aa(aa, property = "Z", T = 25, P = "Psat", pH = 7, ret.val = NULL, suppress.Cys = FALSE)
aa |
data frame, amino acid composition in the format of |
property |
character, property to calculate |
T |
numeric, temperature in °C |
P |
numeric, pressure in bar, or ‘Psat’ for vapor pressure of H2O above 100 °C |
pH |
numeric, pH |
ret.val |
character, return the indicated value from intermediate calculations |
suppress.Cys |
logical, suppress (ignore) the ionization of the cysteine groups? |
The properties of ionization of proteins calculated by this function take account of the standard molal thermodynamic properties of ionizable amino acid sidechain groups and the terminal groups in proteins ([AABB]) and their equations of state parameters taken from Dick et al., 2006. The values of the ionization constants (pK) are calculated as a function of temperature, and the charges and the ionization contributions of other thermodynamic properties to the proteins are calculated additively, without consideration of electrostatic interactions, so they are best applied to the unfolded protein reference state.
For each amino acid composition in aa
, the additive value of the property
is calculated as a function of T
, P
and pH
. property
can be NULL to denote net charge, or if not NULL is one of the properties available in subcrt
, or is ‘A’ to calculate the dimensionless chemical affinity (A/2.303RT) of the ionization reaction for the protein. If ret.val
is one of ‘pK’, ‘alpha’, or ‘aavals’ it indicates to return the value of the ionization constant, degree of formation, or the values of the property
for each ionizable group rather than taking their sums for the amino acid compositions in aa
.
The function returns a matrix (possibly with only one row or column) with number of rows corresponding to the longest of T
, P
or pH
(values of any of these with shorter length are recycled) and a column for each of the amino acid compositions in aa
.
Dick, J. M., LaRowe, D. E. and Helgeson, H. C. (2006) Temperature, pressure, and electrochemical constraints on protein speciation: Group additivity calculation of the standard molal thermodynamic properties of ionized unfolded proteins. Biogeosciences 3, 311–336. doi:10.5194/bg-3-311-2006
Makhatadze, G. I. and Privalov, P. L. (1990) Heat capacity of proteins. 1. Partial molar heat capacity of individual amino acid residues in aqueous solution: Hydration effect. J. Mol. Biol. 213, 375–384. doi:10.1016/S0022-2836(05)80197-4
Privalov, P. L. and Makhatadze, G. I. (1990) Heat capacity of proteins. II. Partial molar heat capacity of the unfolded polypeptide chain of proteins: Protein unfolding effects. J. Mol. Biol. 213, 385–391. doi:10.1016/S0022-2836(05)80198-6
## Heat capacity of LYSC_CHICK as a function of T pH <- c(5, 9, 3) T <- seq(0, 100) # Cp of non-ionized protein Cp.nonion <- subcrt("LYSC_CHICK", T = T)$out[[1]]$Cp plot(T, Cp.nonion, xlab = axis.label("T"), type = "l", ylab = axis.label("Cp"), ylim = c(20000, 35000)) # Cp of ionization and ionized protein aa <- pinfo(pinfo("LYSC_CHICK")) for(pH in c(5, 9, 3)) { Cp.ionized <- Cp.nonion + ionize.aa(aa, "Cp", T = T, pH = pH)[, 1] lines(T, Cp.ionized, lty = 2) text(80, Cp.ionized[70], paste("pH =", pH) ) } # Makhatadze and Privalov's group contributions T <- c(5, 25, 50, 75, 100, 125) points(T, MP90.cp("LYSC_CHICK", T)) # Privalov and Makhatadze's experimental values e <- read.csv(system.file("extdata/cpetc/PM90.csv", package = "CHNOSZ")) points(e$T, e$LYSC_CHICK, pch = 16) legend("bottomright", pch = c(16, 1, NA, NA), lty = c(NA, NA, 1, 2), legend = c("PM90 experiment", "MP90 groups", "DLH06 groups no ion", "DLH06 groups ionized")) title("Heat capacity of unfolded LYSC_CHICK")
## Heat capacity of LYSC_CHICK as a function of T pH <- c(5, 9, 3) T <- seq(0, 100) # Cp of non-ionized protein Cp.nonion <- subcrt("LYSC_CHICK", T = T)$out[[1]]$Cp plot(T, Cp.nonion, xlab = axis.label("T"), type = "l", ylab = axis.label("Cp"), ylim = c(20000, 35000)) # Cp of ionization and ionized protein aa <- pinfo(pinfo("LYSC_CHICK")) for(pH in c(5, 9, 3)) { Cp.ionized <- Cp.nonion + ionize.aa(aa, "Cp", T = T, pH = pH)[, 1] lines(T, Cp.ionized, lty = 2) text(80, Cp.ionized[70], paste("pH =", pH) ) } # Makhatadze and Privalov's group contributions T <- c(5, 25, 50, 75, 100, 125) points(T, MP90.cp("LYSC_CHICK", T)) # Privalov and Makhatadze's experimental values e <- read.csv(system.file("extdata/cpetc/PM90.csv", package = "CHNOSZ")) points(e$T, e$LYSC_CHICK, pch = 16) legend("bottomright", pch = c(16, 1, NA, NA), lty = c(NA, NA, 1, 2), legend = c("PM90 experiment", "MP90 groups", "DLH06 groups no ion", "DLH06 groups ionized")) title("Heat capacity of unfolded LYSC_CHICK")
Fit thermodynamic parameters to experimental formation constants for an aqueous species and add the parameters to OBIGT.
logB.to.OBIGT(logB, species, coeffs, T, P, npar = 3, optimize.omega = FALSE, tolerance = 0.05)
logB.to.OBIGT(logB, species, coeffs, T, P, npar = 3, optimize.omega = FALSE, tolerance = 0.05)
logB |
Values of log β |
species |
Species in the formation reaction (the formed species must be last) |
coeffs |
Coefficients of the formation reaction |
T |
Temperature (units of |
P |
Temperature (‘Psat’ or numerical values with units of |
npar |
numeric, number of parameters to use in fitting |
optimize.omega |
logical, optimize the omega parameter (relevant for charged species)? |
tolerance |
Tolerance for checking equivalence of input and calculated log β values |
This function updates the OBIGT
thermodynamic database with parameters fit to formation constants of aqueous species as a function of temperature.
The logB
argument should have decimal logarithm of formation constants for an aqueous complex (log β).
The formation reaction is defined by species
and coeffs
.
All species in the formation reaction must be present in OBIGT except for the last species, which is the newly formed species.
The function works as follows.
First, the properties of the known species are combined with log β to calculate the standard Gibbs energy (G[T]) of the formed species at each value of T
and P
.
Then, lm
is used to fit one or more of the thermodynamic parameters G
, S
, c1
, c2
, and omega
to the values of G[T].
The first two of these parameters are standard-state values at 25 °C and 1 bar, and the last three are parameters in the revised HKF equations (e.g. Eq. B25 of Shock et al., 1992).
The fitted parameters for the formed species are then added to OBIGT.
Finally, all.equal
is used to test for approximate equivalence of the input values of log β and calculated equilibrium constants; if the mean absolute difference exceeds tolerance
, an error occurs.
To avoid overfitting, only the first three parameters (G
, S
, and c1
) are used by default.
More parameters (up to 5) or fewer (down to 1) can be selected by changing npar
.
Volumetric parameters (a1 to a4) in the HKF equations currently aren't included, so the resulting fits are valid only at the input pressure values.
Independent of npar
, the number of parameters used in the fit is not more than the number of data values (n).
If n is less than 5, then the values of the unused parameters are set to 0 for addition to OBIGT.
For instance, a single value of log β would be fit only with G
, implying that computed values of G[T] have no temperature dependence.
The value of ω is a constant in the revised HKF equations for uncharged species, but for charged species, it is a function of T and P as described by the “g function” (Shock et al., 1992).
An optimization step is available to refine the value of omega
at 25 °C and 1 bar for charged species taking its temperature dependence into account for the fitting.
However, representative datasets are not well represented by variable omega
(see first example), so this step is skipped by default.
Furthermore, logB.to.OBIGT
by default also sets the z
parameter in OBIGT to 0; this enforces a constant ω for charged species in calculations with subcrt
(note that this is a parameter for the HKF equations and does not affect reaction balancing).
Set optimize.omega
to TRUE to override the defaults and activate variable ω for charged species; this takes effect only if npar == 5
and n > 5.
The species index of the new species in OBIGT.
Migdisov, Art. A., Zezin, D. and Williams-Jones, A. E. (2011) An experimental study of Cobalt (II) complexation in Cl- and H2S-bearing hydrothermal solutions. Geochim. Cosmochim. Acta 75, 4065–4079. doi:10.1016/j.gca.2011.05.003
Mei, Y., Sherman, D. M., Liu, W., Etschmann, B., Testemale, D. and Brugger, J. (2015) Zinc complexation in chloride-rich hydrothermal fluids (25–600 °C): A thermodynamic model derived from ab initio molecular dynamics. Geochim. Cosmochim. Acta 150, 264–284. doi:10.1016/j.gca.2014.09.023
Shock, E. L., Oelkers, E. H., Johnson, J. W., Sverjensky, D. A. and Helgeson, H. C. (1992) Calculation of the thermodynamic properties of aqueous species at high pressures and temperatures: Effective electrostatic radii, dissociation constants and standard partial molal properties to 1000 °C and 5 kbar. J. Chem. Soc. Faraday Trans. 88, 803–826. doi:10.1039/FT9928800803
logB.to.OBIGT
calls mod.OBIGT
with zap = TRUE
to clear the parameters of a formed species if it already exists in the OBIGT database.
If preexisting parameters (e.g. volumetric HKF coefficients) weren't cleared, they would interfere with the fitting done here, which uses only selected parameters.
## CoHS+ from Migdisov et al. (2011) logB <- c(6.24, 6.02, 5.84, 5.97, 6.52) T <- c(120, 150, 200, 250, 300) P <- "Psat" species <- c("Co+2", "HS-", "CoHS+") coeffs <- c(-1, -1, 1) opar <- par(mfrow = c(2, 1)) for(o.o in c(TRUE, FALSE)) { # Fit the parameters with or without variable omega inew <- logB.to.OBIGT(logB, species, coeffs, T, P, npar = 5, optimize.omega = o.o) # Print the new database entry info(inew) # Plot experimental logB plot(T, logB, "n", c(100, 320), c(5.8, 6.8), xlab = axis.label("T"), ylab = quote(log~beta)) points(T, logB, pch = 19, cex = 2) # Plot calculated values Tfit <- seq(100, 320, 10) sres <- subcrt(species, coeffs, T = Tfit) lines(sres$out$T, sres$out$logK, col = 4) title(describe.reaction(sres$reaction)) legend <- c("Migdisov et al. (2011)",paste0("logB.to.OBIGT(optimize.omega = ",o.o,")")) legend("top", legend, pch = c(19, NA), lty = c(0, 1), col = c(1, 4), pt.cex = 2, bg = "#FFFFFFB0") } par(opar) # NB. Optimizing omega leads to unphysical oscillations in the logK (first plot) ## ZnCl+ from Mei et al. (2015) # Values for 5000 bar calculated with the modified Ryzhenko-Bryzgalin (RB) model logB <- c(-1.93,-1.16,-0.38,0.45,1.15,1.76,2.30,2.80,3.26,3.70,4.12,4.53,4.92) species <- c("Zn+2", "Cl-", "ZnCl+") coeffs <- c(-1, -1, 1) T <- c(25, 60, 100, 150, 200, 250, 300, 350, 400, 450, 500, 550, 600) P <- 5000 # Note: ZnCl+ is in the default OBIGT database; # logB.to.OBIGT() "zaps" the previous parameters before adding the fitted ones inew <- logB.to.OBIGT(logB, species, coeffs, T, P, npar = 5) # Plot RB and logB.to.OBIGT values plot(T, logB, xlab = axis.label("T"), ylab = axis.label("logB"), pch = 19, cex = 2) Tfit <- seq(25, 600, 25) sres <- subcrt(species, coeffs, T = Tfit, P = P) lines(sres$out$T, sres$out$logK, col = 4) title(describe.reaction(sres$reaction), line = 3) title("5000 bar", font.main = 1, line = 1) legend <- c("Mei et al. (2015)", "logB.to.OBIGT()") legend("topleft", legend, pch = c(19, NA), lty = c(0, 1), col = c(1, 4), pt.cex = 2)
## CoHS+ from Migdisov et al. (2011) logB <- c(6.24, 6.02, 5.84, 5.97, 6.52) T <- c(120, 150, 200, 250, 300) P <- "Psat" species <- c("Co+2", "HS-", "CoHS+") coeffs <- c(-1, -1, 1) opar <- par(mfrow = c(2, 1)) for(o.o in c(TRUE, FALSE)) { # Fit the parameters with or without variable omega inew <- logB.to.OBIGT(logB, species, coeffs, T, P, npar = 5, optimize.omega = o.o) # Print the new database entry info(inew) # Plot experimental logB plot(T, logB, "n", c(100, 320), c(5.8, 6.8), xlab = axis.label("T"), ylab = quote(log~beta)) points(T, logB, pch = 19, cex = 2) # Plot calculated values Tfit <- seq(100, 320, 10) sres <- subcrt(species, coeffs, T = Tfit) lines(sres$out$T, sres$out$logK, col = 4) title(describe.reaction(sres$reaction)) legend <- c("Migdisov et al. (2011)",paste0("logB.to.OBIGT(optimize.omega = ",o.o,")")) legend("top", legend, pch = c(19, NA), lty = c(0, 1), col = c(1, 4), pt.cex = 2, bg = "#FFFFFFB0") } par(opar) # NB. Optimizing omega leads to unphysical oscillations in the logK (first plot) ## ZnCl+ from Mei et al. (2015) # Values for 5000 bar calculated with the modified Ryzhenko-Bryzgalin (RB) model logB <- c(-1.93,-1.16,-0.38,0.45,1.15,1.76,2.30,2.80,3.26,3.70,4.12,4.53,4.92) species <- c("Zn+2", "Cl-", "ZnCl+") coeffs <- c(-1, -1, 1) T <- c(25, 60, 100, 150, 200, 250, 300, 350, 400, 450, 500, 550, 600) P <- 5000 # Note: ZnCl+ is in the default OBIGT database; # logB.to.OBIGT() "zaps" the previous parameters before adding the fitted ones inew <- logB.to.OBIGT(logB, species, coeffs, T, P, npar = 5) # Plot RB and logB.to.OBIGT values plot(T, logB, xlab = axis.label("T"), ylab = axis.label("logB"), pch = 19, cex = 2) Tfit <- seq(25, 600, 25) sres <- subcrt(species, coeffs, T = Tfit, P = P) lines(sres$out$T, sres$out$logK, col = 4) title(describe.reaction(sres$reaction), line = 3) title("5000 bar", font.main = 1, line = 1) legend <- c("Mei et al. (2015)", "logB.to.OBIGT()") legend("topleft", legend, pch = c(19, NA), lty = c(0, 1), col = c(1, 4), pt.cex = 2)
Count the elements and charges in a chemical formula.
makeup(formula, multiplier = 1, sum = FALSE, count.zero = FALSE) count.elements(formula)
makeup(formula, multiplier = 1, sum = FALSE, count.zero = FALSE) count.elements(formula)
formula |
character, a chemical formula |
multiplier |
numeric, multiplier for the elemental counts in each formula |
sum |
logical, add together the elemental counts in all formulas? |
count.zero |
logical, include zero counts for elements? |
makeup
parses a chemical formula expressed in string notation, returning the numbers of each element in the formula.
The formula may carry a charge, indicated by a + or - sign, possibly followed by a magnitude, after the uncharged part of the formula.
The formula may have multiple subformulas enclosed in parentheses (but the parentheses may not be nested), each one optionally followed by a numeric coefficient.
The formula may have one suffixed subformula, separated by ‘*’ or ‘:’, optionally preceded by a numeric coefficient. All numbers may contain a decimal point.
Each subformula (or the entire formula without subformulas) should be a simple formula.
A simple formula, processed by count.elements
, must adhere to the following pattern: it starts with an elemental symbol; all elemental symbols start with an uppercase letter, and are followed by another elemental symbol, a number (possibly fractional, possibly signed), or nothing (the end of the formula).
Any sequence of one uppercase letter followed by zero or more lowercase letters is recognized as an elemental symbol.
makeup
will issue a warning for elemental symbols that are not present in thermo$element
.
makeup
can handle numeric and length > 1 values for the formula
argument.
If the argument is numeric, it identifies row number(s) in thermo()$OBIGT
from which to take the formulas of species.
If formula
has length > 1, the function returns a list containing the elemental counts in each of the formulas.
If count.zero
is TRUE, the elemental counts for each formula include zeros to indicate elements that are only present in any of the other formulas.
The multiplier
argument must have either length = 1 or length equal to the number of formulas.
The elemental count in each formula is multiplied by the respective value.
If sum
is true, the elemental counts in all formulas (after any multiplying) are summed together to yield a single bulk formula.
A numeric vector with names refering to each of the elemental symbols in the formula.
If more than one formula is provided, a list of numeric vectors is returned, unless sum
is TRUE.
# Elemental composition of a simple compound makeup("CO2") # 1 carbon, 2 oxygen # Formula of lawsonite, with a parenthetical part and a suffix makeup("CaAl2Si2O7(OH)2*H2O") # Fractional coefficients are OK reddiv10 <- makeup("C10.6N1.6P0.1") 10*reddiv10 # 106, 16, 1 (Redfield ratio) # The coefficient for charge is a number with a *preceding* sign # e.g., ferric iron, with a charge of +3 is expressed as makeup("Fe+3") # Transcribing the formula the way it appears in many # publications produces a likely unintended result: # 3 iron atoms and a charge of +1 makeup("Fe3+") # These all represent a single negative charge, i.e., electron makeup("-1") makeup("Z-1+0") makeup("Z0-1") # the "old" formula for the electron in thermo()$OBIGT makeup("(Z-1)") # the current formula in thermo()$OBIGT # Hypothetical compounds with negative numbers of elements makeup("C-4(O-2)") # -4 carbon, -2 oxygen makeup("C-4O-2") # -4 carbon, 1 oxygen, -2 charge makeup("C-4O-2-2") # -4 carbon, -2 oxygen, -2 charge # The 'sum' argument can be used to check mass and charge # balance in a chemical reaction formula <- c("H2O", "H+", "(Z-1)", "O2") mf <- makeup(formula, c(-1, 2, 2, 0.5), sum = TRUE) all(mf == 0) # TRUE
# Elemental composition of a simple compound makeup("CO2") # 1 carbon, 2 oxygen # Formula of lawsonite, with a parenthetical part and a suffix makeup("CaAl2Si2O7(OH)2*H2O") # Fractional coefficients are OK reddiv10 <- makeup("C10.6N1.6P0.1") 10*reddiv10 # 106, 16, 1 (Redfield ratio) # The coefficient for charge is a number with a *preceding* sign # e.g., ferric iron, with a charge of +3 is expressed as makeup("Fe+3") # Transcribing the formula the way it appears in many # publications produces a likely unintended result: # 3 iron atoms and a charge of +1 makeup("Fe3+") # These all represent a single negative charge, i.e., electron makeup("-1") makeup("Z-1+0") makeup("Z0-1") # the "old" formula for the electron in thermo()$OBIGT makeup("(Z-1)") # the current formula in thermo()$OBIGT # Hypothetical compounds with negative numbers of elements makeup("C-4(O-2)") # -4 carbon, -2 oxygen makeup("C-4O-2") # -4 carbon, 1 oxygen, -2 charge makeup("C-4O-2-2") # -4 carbon, -2 oxygen, -2 charge # The 'sum' argument can be used to check mass and charge # balance in a chemical reaction formula <- c("H2O", "H+", "(Z-1)", "O2") mf <- makeup(formula, c(-1, 2, 2, 0.5), sum = TRUE) all(mf == 0) # TRUE
Combine diagrams for different systems by mashing or rebalancing two diagrams or mixing two diagrams with a third.
mash(d1, d2) rebalance(d1, d2, balance = NULL) mix(d1, d2, d3, parts = c(1, 1), .balance = NULL)
mash(d1, d2) rebalance(d1, d2, balance = NULL) mix(d1, d2, d3, parts = c(1, 1), .balance = NULL)
d1 |
list, output of |
d2 |
list, output of |
balance |
character or numeric, specification of secondary balancing coefficients |
d3 |
list, output of |
parts |
numeric, amount of each metal (i.e. fixed composition) for the mixed system |
.balance |
argument for internal use only |
These functions make a new affinity
object from the output of diagram
.
The result can be used to make a new diagram that shows the combined system.
mash
creates a set of intersecting predominance fields for all possible combinations of species in d1
and d2
.
The new names are formed from the names
used in the source diagrams; for example if "Cp" and "Py" are predominant minerals at the same position in diagrams 1 and 2, the field for the mashed diagram will be labeled "Cp+Py".
The affinities are calculated by summing the formation reactions from the two diagrams to give equal parts of the balancing coefficients in d1
and d2
(that is, equal parts of two different metals).
Note that the actual values of the affinities (and therefore the ratio between the metals) doesn't affect the resulting diagram because the affinities are assigned values of -Inf wherever one of the species is not predominant in the respective single-metal diagram.
mix
is an expanded form of mash
that allows combinations not only between two single-metal diagrams (d1
and d2
) but also between each of those diagrams and third diagram for bimetallic species (d3
).
All combinations of species in all crosses between the diagrams (d1-d2
, d1-d3
, d2-d3
, d3-d3
) are identified.
The mole fractions of species in each combination are computed to satisfy the ratio of metals defined in parts
.
For example, if d1
and d2
are balanced on Fe+2 and VO4-3, the species are combined by default to give equal parts of Fe and V.
Note that pairs of bimetallic species in d3
are included as well as single bimetallic species that satisfy the composition in parts
(e.g. FeV for c(1, 1)
or Fe3V for c(3, 1)
).
From the possible combinations of species, combinations are removed that have a negative mole fraction of any species or that involve any mono-metallic species that has no predominance field in the corresponding single-metal diagram.
The output consists of each unique combination of species, including the combined formation reactions and affinities (in the species
and values
elements of the output list),
The affinities are assigned values of -Inf wherever one of the species is not predominant in the respective single-metal diagram.
Therefore, either the single-metal diagrams (d1
or d2
) can be recovered by setting parts
to c(1, 0)
or c(0, 1)
, respectively.
NOTE: Unlike the diagram
calls used to make d1
and d2
, which by themselves should produce reasonable diagrams for a single-metal system, the d3
diagram by itself probably has no useful interpretation.
It is only used in mix
as a way to transmit the results of affinity
for the bimetmal system and the formatted names that are made by diagram
.
rebalance
creates a new set of affinities of reactions between species in both systems.
Diagrams for different systems likely use different primary balancing coefficients, such as balancing on different metals.
rebalance
uses secondary balancing coefficients, specified acording to balance
(see equilibrate
for a description of this argument), to determine the reactions between the species in the two systems.
The affinities of these reactions are then used only to identify the predominant species at each grid point.
The returned value of affinity are carried forward from those used to make the source diagrams (‘plotvals’ in d1
and d2
), and therefore reflect the primary balancing coefficients.
The returned values are assigned -Inf wherever that species is determined to not predominate according to the secondary balancing.
Because mash
yields finite values of affinity for only a single species at any grid point, the final diagram can be made with any setting of balance
.
mix
gives combinations of species that each have the amount of metals defined in parts
, so it makes no difference whether the final diagram is balanced on either of the metals, or on formula units (balance = 1
).
However, for rebalance
, balance
in the final diagram should be set to ‘1’ to balance on formula units in order to preserve the primary balancing coefficients.
A list object with the same structure as the output from affinity
, so it can be used as input to diagram
.
More examples are in the vignette multi-metal.
par(mfrow = c(2, 2)) # Define basis species with Fe and Cu basis(c("Fe+2", "Cu+", "hydrogen sulfide", "oxygen", "H2O", "H+")) xlab <- ratlab("Fe+2", "Cu+") # Calculate diagram for only Fe-bearing minerals species(c("pyrite", "pyrrhotite", "magnetite", "hematite")) aFe <- affinity("Fe+2" = c(0, 12), O2 = c(-40, -16), T = 400, P = 2000) dFe <- diagram(aFe, xlab = xlab, main = "Fe-S-O-H") # Calculate diagram for only Cu-bearing minerals species(c("covellite", "chalcocite", "tenorite", "cuprite")) aCu <- affinity(aFe) # argument recall dCu <- diagram(aCu, xlab = xlab, main = "Cu-S-O-H") ### mash() diagram ac <- mash(dFe, dCu) diagram(ac, xlab = xlab, main = "Cu-Fe-S-O-H with mash()") ### rebalance() diagram ad <- rebalance(dFe, dCu) diagram(ad, xlab = xlab, balance = 1, main = "Cu-Fe-S-O-H with rebalance()") db <- describe.basis(3) leg <- lex(lTP(400, 2000), db) legend("bottomleft", legend = leg, bty = "n")
par(mfrow = c(2, 2)) # Define basis species with Fe and Cu basis(c("Fe+2", "Cu+", "hydrogen sulfide", "oxygen", "H2O", "H+")) xlab <- ratlab("Fe+2", "Cu+") # Calculate diagram for only Fe-bearing minerals species(c("pyrite", "pyrrhotite", "magnetite", "hematite")) aFe <- affinity("Fe+2" = c(0, 12), O2 = c(-40, -16), T = 400, P = 2000) dFe <- diagram(aFe, xlab = xlab, main = "Fe-S-O-H") # Calculate diagram for only Cu-bearing minerals species(c("covellite", "chalcocite", "tenorite", "cuprite")) aCu <- affinity(aFe) # argument recall dCu <- diagram(aCu, xlab = xlab, main = "Cu-S-O-H") ### mash() diagram ac <- mash(dFe, dCu) diagram(ac, xlab = xlab, main = "Cu-Fe-S-O-H with mash()") ### rebalance() diagram ad <- rebalance(dFe, dCu) diagram(ad, xlab = xlab, balance = 1, main = "Cu-Fe-S-O-H with rebalance()") db <- describe.basis(3) leg <- lex(lTP(400, 2000), db) legend("bottomleft", legend = leg, bty = "n")
Calculate chemical affinities of formation reactions of species using basis species that change with the conditions.
mosaic(bases, blend = TRUE, stable = list(), loga_aq = NULL, ...)
mosaic(bases, blend = TRUE, stable = list(), loga_aq = NULL, ...)
bases |
character, basis species to be changed in the calculation, or list, each element of which defines an independent group of changing basis species |
blend |
logical, use relative abundances of basis species? |
stable |
list, previously determined stable species |
loga_aq |
numeric, activities of aqueous species (overrides current values in |
... |
additional arguments to be passed to |
mosaic
calculates the affinities of formation of species when the relative abundances of the basis species listed in bases
change over the range of conditions, due to e.g. ionization, complexation or redox reactions.
This is a way to “speciate the basis species”.
For example, the speciation of sulfur (‘SO4-2’, ‘HSO4-’, ‘HS-’ and ‘H2S’) as a function of Eh and pH affects the formation affinities, and therefore relative stabilities of iron oxide and sulfide minerals.
Chemical activity diagrams constructed by assembling sub-diagrams corresponding to the predominant (i.e. most stable) basis species can described as “mosaic diagrams”.
The function calculates the affinities using all combination of basis species given as a vector argument to bases
.
Or, a list can be provided contain any number of vectors that specify different groups of basis species.
All combinations of basis species in these groups are used for the calculations.
The first species listed in each group should be in the current basis definition, and all the basis species in each group should be related to the first basis species there (i.e. all share the same element).
The arguments in ...
are passed to affinity
to specify the variable conditions, such as temperature, pressure, and activities of other basis species.
blend
can be a single logical value or multiple values, in order to control the calculations for individual groups of basis species.
If blend
is TRUE (the default), the relative abundances of the basis species in each group are calculated using equilibrate
, with the total activity taken from the corresponding basis species in the incoming basis
definition.
Then, the function calculates overall affinities of the formation reactions of each species by combining reactions written using individual basis species in proportion to the relative abundances of the basis species.
If blend
is FALSE, the function returns the affinities calculated using the single predominant basis species in bases
at each condition.
This is appropriate when minerals, rather than aqueous species, are used as the changing basis species.
Note, however, that mosaic
is not internally recursive: the stabilities of one group of basis species (e.g. minerals) are not affected by changes in another group (e.g. aqueous species).
(“Stacked mosaic diagrams”) are useful for making diagrams for multi-metal systems.
By using the stable minerals in one calculation as the new basis species in a subsequent calculation, a series of stacked mosaic
diagrams with increasing complexity can be made.
Specifically, this is done by supplying previously calculated stabilities (from the predominant
element of the output of diagram
) as an element of the list in the stable
argument whose position corresponds to the appropriate group of basis species.
Note that a value in any position of the stable
list forces blend = FALSE
for the corresponding group of basis species, so there is no need to explicity change the blend
argument.
The activities of mosaiced basis species in each group are taken from the current basis
definition.
Generally it makes sense to set the activity of minerals to 1 (logact = 0) and the activity of aqueous species to some smaller value.
For mosaic stacking calculations where the mosaiced basis species include both minerals and aqueous species, the loga_aq
argument specifies the activity of aqueous species to be used in each group.
That is, there should be one value of loga_aq
for each group of basis species; use NA to indicate that the activity comes from the current basis
definition.
See the Mosaic Stacking 2 section of the vignette multi-metal for an example.
A list containing A.species
(affinities of formation of the species with changing basis species) and A.bases
(affinities of formation of the basis species in terms of the first basis species), each having same structure as the list returned by affinity
.
If bases
is a list, A.bases
is also a list, each element of which corresponds to a group of basis species in bases
.
If blend
is TRUE, the output also contains E.bases
(the output of equilibrate
for each group of basis species)
Garrels, R. M. and Christ, C. L. (1965) Solutions, Minerals, and Equilibria, Harper & Row, New York, 450 p. https://www.worldcat.org/oclc/517586
demo("mosaic")
, which extends the example below with carbonate species in order to plot a siderite field.
To calculate mineral solubilities with mosaic calculations that account for ligand speciation, use bases
as the first argument to solubility
.
stack_mosaic
implements calculations for bimetallic systems.
# Fe-minerals and aqueous species in Fe-S-O-H system # Speciate SO4-2, HSO4-, HS-, and H2S as a function of Eh and pH # After Garrels and Christ, 1965 Figure 7.20 pH <- c(0, 14) Eh <- c(-1, 1) T <- 25 basis(c("FeO", "SO4-2", "H2O", "H+", "e-")) basis("SO4-2", -6) species(c("Fe+2", "Fe+3"), -6) species(c("pyrrhotite", "pyrite", "hematite", "magnetite"), add = TRUE) # The basis species we'll swap through bases <- c("SO4-2", "HSO4-", "HS-", "H2S") # Calculate affinities using the relative abundances of the basis species # NOTE: set blend = FALSE for sharp transitions between the basis species # (looks more like the diagram in GC65) m1 <- mosaic(bases, pH = pH, Eh = Eh, T = T) # Make a diagram and add water stability lines d <- diagram(m1$A.species, lwd = 2) water.lines(d, col = "seagreen", lwd = 1.5) # Show lines for Fe(aq) = 10^-4 M species(c("Fe+2", "Fe+3"), -4) m2 <- mosaic(bases, pH = pH, Eh = Eh, T = T) diagram(m2$A.species, add = TRUE, names = FALSE) title(main=paste("Iron oxides and sulfides in water, log(total S) = -6", "After Garrels and Christ, 1965", sep="\n")) legend("bottomleft", c("log(act_Fe) = -4", "log(act_Fe) = -6"), lwd = c(2, 1), bty = "n") # We could overlay the predominance fields for the basis species #diagram(m1$A.bases, add = TRUE, col = "blue", col.names = "blue", lty = 3)
# Fe-minerals and aqueous species in Fe-S-O-H system # Speciate SO4-2, HSO4-, HS-, and H2S as a function of Eh and pH # After Garrels and Christ, 1965 Figure 7.20 pH <- c(0, 14) Eh <- c(-1, 1) T <- 25 basis(c("FeO", "SO4-2", "H2O", "H+", "e-")) basis("SO4-2", -6) species(c("Fe+2", "Fe+3"), -6) species(c("pyrrhotite", "pyrite", "hematite", "magnetite"), add = TRUE) # The basis species we'll swap through bases <- c("SO4-2", "HSO4-", "HS-", "H2S") # Calculate affinities using the relative abundances of the basis species # NOTE: set blend = FALSE for sharp transitions between the basis species # (looks more like the diagram in GC65) m1 <- mosaic(bases, pH = pH, Eh = Eh, T = T) # Make a diagram and add water stability lines d <- diagram(m1$A.species, lwd = 2) water.lines(d, col = "seagreen", lwd = 1.5) # Show lines for Fe(aq) = 10^-4 M species(c("Fe+2", "Fe+3"), -4) m2 <- mosaic(bases, pH = pH, Eh = Eh, T = T) diagram(m2$A.species, add = TRUE, names = FALSE) title(main=paste("Iron oxides and sulfides in water, log(total S) = -6", "After Garrels and Christ, 1965", sep="\n")) legend("bottomleft", c("log(act_Fe) = -4", "log(act_Fe) = -6"), lwd = c(2, 1), bty = "n") # We could overlay the predominance fields for the basis species #diagram(m1$A.bases, add = TRUE, col = "blue", col.names = "blue", lty = 3)
Calculate speciation and ionic strength of aqueous solutions with a given molality of NaCl.
NaCl(m_tot = 1, T = 25, P = "Psat", pH = NA, attenuate = FALSE)
NaCl(m_tot = 1, T = 25, P = "Psat", pH = NA, attenuate = FALSE)
m_tot |
numeric, total molality of NaCl (single value) |
T |
numeric, temperature in °C |
P |
numeric, pressure in bar |
pH |
numeric, pH |
attenuate |
logical, halve changes of variables in each step? |
Thermodynamic models for metal solubility and speciation involving chloride complexes are commonly specified in terms of amount of NaCl rather than activity (or molality) of Cl- as an independent variable.
This function calculates distribution of species and ionic strength in a simple aqueous solution given a total amount (m_tot
, in mol/kg) of NaCl.
The aqueous Cl-bearing species considered in the system are Cl-, NaCl, and optionally HCl.
Na+ is present as a basis species, but the formation of Na-bearing species such as NaOH is not considered.
The activity coefficients of charged species are calculated using the extended Debye-Hückel equation (see nonideal
) via the IS
argument of affinity
.
The function first sets the molality of Na+ and ionic strength equal to m_tot
, then calculates the distribution of Cl-bearing species.
Based on mass balance of Na atoms, the molality of NaCl is then used to recalculate the molality of Na+, followed by ionic strength.
To find a solution, the function iterates until the change of molality of Na+ and ionic strength are both less than m_tot
/ 100.
At very high NaCl concentrations, which are beyond the applicability limits of the extended Debye-Hückel model and therefore not recommended for normal use, the iterations tend to oscillate without converging.
Setting attenuate
to TRUE, which halves the amount of change in each step, may help with convergence.
If a solution is not found after 100 iterations, the function stops with an error.
If pH
is NA (the default), then HCl is not included in the calculation and its molality in the output is also assigned NA.
Note that only a single value is accepted for m_tot
, but the other numeric arguments can have length > 1, allowing multiple combinations T
, P
, and pH
in a single function call.
However, due to limitations in affinity
, only one of T
and P
can have length > 1.
A list with components ‘IS’ (ionic strength calculated from molalities of Na+ and Cl-), ‘m_Cl’, ‘m_Cl’, ‘m_NaCl’, and ‘m_HCl’ (molalities of Na+, Cl-, NaCl, and HCl).
It is important to keep in mind the ionic strength limits of the Debye-Hückel equation, but this function doesn't enforce them. Furthermore, metal-ligand complexing is not calculated by this function, so metal solubility and speciation calculations will be accurate only for relatively insoluble metals in NaCl-dominated solutions.
Shvarov, Y. and Bastrakov, E. (1999) HCh: A software package for geochemical equilibrium modelling. User's Guide. Australian Geological Survey Organisation 1999/25. https://pid.geoscience.gov.au/dataset/ga/25473
This function is used in a few demos (demo("contour")
, demo("gold")
, demo("minsol")
, demo("sphalerite")
).
demo("yttrium")
uses the pH
argument.
# Ionic strength calculated with HCh version 3.7 (Shvarov and Bastrakov, 1999) # at 1000 bar, 100, 200, and 300 degress C, and 1 to 6 molal NaCl m.HCh <- 1:6 IS.HCh <- list(`100` = c(0.992, 1.969, 2.926, 3.858, 4.758, 5.619), `300` = c(0.807, 1.499, 2.136, 2.739, 3.317, 3.875), `500` = c(0.311, 0.590, 0.861, 1.125, 1.385, 1.642)) # Total molality in the calculation with NaCl() m_tot <- seq(1, 6, 0.5) N <- length(m_tot) # Where we'll put the calculated values IS.calc <- data.frame(`100` = numeric(N), `300` = numeric(N), `500` = numeric(N)) # NaCl() is *not* vectorized over m_tot, so we use a loop here for(i in 1:length(m_tot)) { NaCl.out <- NaCl(m_tot[i], c(100, 300, 500), P = 1000) IS.calc[i, ] <- NaCl.out$IS } # Plot ionic strength from HCh and NaCl() as points and lines col <- c("black", "red", "orange") plot(c(1,6), c(0,6), xlab = "NaCl (mol/kg)", ylab = axis.label("IS"), type = "n") for(i in 1:3) { # NOTE: the differences are probably mostly due to different models # for the properties of NaCl(aq) (HCh: B.Ryhzenko model; # CHONSZ: revised HKF with parameters from Shock et al., 1997) points(m.HCh, IS.HCh[[i]], col = col[i]) lines(m_tot, IS.calc[, i], col = col[i]) } # Add legend and title dprop <- describe.property(rep("T", 3), c(100, 300, 500)) legend("topleft", dprop, lty = 1, pch = 1, col = col) title(main="H2O + NaCl; HCh (points) and 'NaCl()' (lines)")
# Ionic strength calculated with HCh version 3.7 (Shvarov and Bastrakov, 1999) # at 1000 bar, 100, 200, and 300 degress C, and 1 to 6 molal NaCl m.HCh <- 1:6 IS.HCh <- list(`100` = c(0.992, 1.969, 2.926, 3.858, 4.758, 5.619), `300` = c(0.807, 1.499, 2.136, 2.739, 3.317, 3.875), `500` = c(0.311, 0.590, 0.861, 1.125, 1.385, 1.642)) # Total molality in the calculation with NaCl() m_tot <- seq(1, 6, 0.5) N <- length(m_tot) # Where we'll put the calculated values IS.calc <- data.frame(`100` = numeric(N), `300` = numeric(N), `500` = numeric(N)) # NaCl() is *not* vectorized over m_tot, so we use a loop here for(i in 1:length(m_tot)) { NaCl.out <- NaCl(m_tot[i], c(100, 300, 500), P = 1000) IS.calc[i, ] <- NaCl.out$IS } # Plot ionic strength from HCh and NaCl() as points and lines col <- c("black", "red", "orange") plot(c(1,6), c(0,6), xlab = "NaCl (mol/kg)", ylab = axis.label("IS"), type = "n") for(i in 1:3) { # NOTE: the differences are probably mostly due to different models # for the properties of NaCl(aq) (HCh: B.Ryhzenko model; # CHONSZ: revised HKF with parameters from Shock et al., 1997) points(m.HCh, IS.HCh[[i]], col = col[i]) lines(m_tot, IS.calc[, i], col = col[i]) } # Add legend and title dprop <- describe.property(rep("T", 3), c(100, 300, 500)) legend("topleft", dprop, lty = 1, pch = 1, col = col) title(main="H2O + NaCl; HCh (points) and 'NaCl()' (lines)")
Calculate activity coefficients and adjusted molal properties of aqueous species.
nonideal(species, speciesprops, IS, T, P, A_DH, B_DH, m_star = NULL, method = thermo()$opt$nonideal) bgamma(TC, P, showsplines = "")
nonideal(species, speciesprops, IS, T, P, A_DH, B_DH, m_star = NULL, method = thermo()$opt$nonideal) bgamma(TC, P, showsplines = "")
species |
name of method to use, or names or indices of species for which to calculate nonideal properties |
speciesprops |
list of dataframes of species properties |
IS |
numeric, ionic strength(s) used in nonideal calculations, mol kg |
T |
numeric, temperature (K) |
P |
numeric, pressure (bar); required for B-dot or b_gamma equation |
A_DH |
numeric, A Debye-Huckel coefficient; required for B-dot or b_gamma equation |
B_DH |
numeric, B Debye-Huckel coefficient; required for B-dot or b_gamma equation |
m_star |
numeric, total molality of all dissolved species |
method |
character, ‘Bdot’, ‘Bdot0’, ‘bgamma’, ‘bgamma0’, or ‘Alberty’ |
TC |
numeric, temperature (°C) |
showsplines |
character, show isobaric (‘T’) or isothermal (‘P’) splines |
nonideal
calculates activity coefficients and adjusted thermodynamic properties for charged and neutral aqueous species.
At the user level, the main use of this function is to set the method for activity coefficient calculations that gets used by other functions in CHNOSZ.
See the “Charged Species” section for a description of the available methods.
Activity coefficient calculations are activated by setting the IS
argument of subcrt
or affinity
.
Those functions then call nonideal
with all the arguments needed to perform the calculations.
The default is to not apply calculations for the proton (H+) and electron (e-); this makes sense if you are setting the pH, i.e. activity of H+, to some value.
To apply the calculations to H+ and/or e-, change thermo()$opt$ideal.H
or ideal.e
to FALSE (see examples).
For the ‘Alberty’ method, the values of IS
are combined with Alberty's (2003) equation 3.6-1 (extended Debye-Hückel equation with an empirical term valid up to 0.25 M ionic strength) and its derivatives (Alberty, 2001), to calculate adjusted molal properties at the specified ionic strength(s) and temperature(s).
The calculations use the equation for the Debye-Hückel constant given by Clarke and Glew, 1980, which is valid between 0 and 150 °C at saturated water vapor pressure (PSAT).
For the ‘Bdot’ method (the default), the “B-dot” form of the extended Debye-Hückel equation is used.
This equation is valid at ionic strengths up to approximately 3 mol / kg (Hörbrand et al., 2018).
The distance of closest approach for different ions (the “ion size parameter”) is taken from thermo()$Bdot_acirc
; any species not listed in this file is assigned a value of 4.5 Å.
The extended term parameter for NaCl-dominated solutions, known as “B-dot”, is calculated as a function only of temperature (Helgeson, 1969).
To set the extended term parameter to zero, use the ‘Bdot0’ method.
For the ‘bgamma’ method, the “b_gamma” equation is used.
The distance of closest approach is set to a constant (3.72e-8 cm) (e.g., Manning et al., 2013).
The extended term parameter is calculated by calling the bgamma
function.
Alternatively, set the extended term parameter to zero with ‘bgamma0’.
For neutral species, the Setchénow equation is used, as described in Shvarov and Bastrakov, 1999.
If thermo()$opt$Setchenow
is ‘bgamma0’ (the default), the extended term parameter is set to zero and the only non-zero term is the mole fraction to molality conversion factor (using the value of m_star
).
If thermo()$opt$Setchenow
is ‘bgamma’, the extended term paramter is taken from the setting for the charged species (which can be either ‘Bdot’ or ‘bgamma’).
Set thermo()$opt$Setchenow
to any other value to disable the calculations for neutral species.
This information, about the arguments and return values used to perform the calculations, is not normally needed by the user (but the usage is shown in the last example).
For nonideal
, the species can be identified by name or species index in species
.
speciesprops
is a list of dataframes containing the input standard molal properties; normally, at least one column is ‘G’ for Gibbs energy.
The function calculates the *adjusted* properties for given ionic strength (IS
); they are equal to the *standard* values only at IS=0.
The adjusted molal properties that can be calculated include ‘G’, and (currently only with the Alberty method) ‘H’, ‘S’ and ‘Cp’; values of any columns with other names are left untouched.
The lengths of IS
and T
supplied in the arguments should be equal to the number of rows of each dataframe in speciesprops
, or length one to use single values throughout.
In addition to IS
and T
, the ‘Bdot’ and ‘bgamma’ methods depend on values of P
, A_DH
, B_DH
, and m_star
given in the arguments.
m_star
, the total molality of all dissolved species, is used to compute the mole fraction to molality conversion factor.
If m_star
is NULL, it is taken to be equal to IS
, which is an underestimate.
For these methods, ‘G’ is currently the only adjusted molal property that is calculated (but this can be used by subcrt
to calculate adjusted equilibrium constants).
The return value is the same as the input in speciesprops
, except the input standard thermodynamic properties (at IS=0) are replaced by adjusted properties (at higher IS).
For all affected species, a column named loggam
(common (base-10) logarithm of gamma, the activity coefficient) is appended to the output dataframe of species properties.
bgamma
calculates the extended term parameter (written as b_gamma; Helgeson et al., 1981) for activity coefficients in NaCl-dominated solutions at high temperature and pressure.
Data at PSAT and 0.5 to 5 kb are taken from Helgeson (1969, Table 2 and Figure 3) and Helgeson et al. (1981, Table 27) and extrapolated values at 10 to 30 kb from Manning et al. (2013, Figure 11).
Furthermore, the 10 to 30 kb data were used to generate super-extrapolated values at 40, 50, and 60 kb, which may be encountered using the water.DEW
calculations.
If all P
correspond to one of the isobaric conditions, the values of Bdot
at T
are calculated by spline fits to the isobaric data.
Otherwise, particular (dependent on the T
) isobaric spline fits are themselves used to construct isothermal splines for the given values of T
; the isothermal splines are then used to generate the values of Bdot
for the given P
.
To see the splines, set showsplines
to ‘T’ to make the first set (isobaric splines) along with the data points, or ‘P’ for examples of isothermal splines at even temperature intervals (here, the symbols are not data, but values generated from the isobaric splines).
This is a basic method of interpolating the data without adding any external dependencies.
Alberty, R. A. (2001) Effect of temperature on standard transformed Gibbs energies of formation of reactants at specified pH and ionic strength and apparent equilibrium constants of biochemical reactions. J. Phys. Chem. B 105, 7865–7870. doi:10.1021/jp011308v
Alberty, R. A. (2003) Thermodynamics of Biochemical Reactions, John Wiley & Sons, Hoboken, New Jersey, 397 p. https://www.worldcat.org/oclc/51242181
Clarke, E. C. W. and Glew, D. N. (1980) Evaluation of Debye-Hückel limiting slopes for water between 0 and 150 °C. J. Chem. Soc. Faraday Trans. 76, 1911–1916. doi:10.1039/f19807601911
Helgeson, H. C. (1969) Thermodynamics of hydrothermal systems at elevated temperatures and pressures. Am. J. Sci. 267, 729–804. doi:10.2475/ajs.267.7.729
Helgeson, H. C., Kirkham, D. H. and Flowers, G. C. (1981) Theoretical prediction of the thermodynamic behavior of aqueous electrolytes at high pressures and temperatures. IV. Calculation of activity coefficients, osmotic coefficients, and apparent molal and standard and relative partial molal properties to 600°C and 5 Kb. Am. J. Sci. 281, 1249–1516. doi:10.2475/ajs.281.10.1249
Hörbrand, T., Baumann, T. and Moog, H. C. (2018) Validation of hydrogeochemical databases for problems in deep geothermal energy. Geotherm. Energy 6, 20. doi:10.1186/s40517-018-0106-3
Manning, C. E. (2013) Thermodynamic modeling of fluid-rock interaction at mid-crustal to upper-mantle conditions. Rev. Mineral. Geochem. 76, 135–164. doi:10.2138/rmg.2013.76.5
Manning, C. E., Shock, E. L. and Sverjensky, D. A. (2013) The chemistry of carbon in aqueous fluids at crustal and upper-mantle conditions: Experimental and theoretical constraints. Rev. Mineral. Geochem. 75, 109–148. doi:10.2138/rmg.2013.75.5
Shvarov, Y. and Bastrakov, E. (1999) HCh: A software package for geochemical equilibrium modelling. User's Guide. Australian Geological Survey Organisation 1999/25. https://pid.geoscience.gov.au/dataset/ga/25473
## Each of the available methods nonideal("Alberty") nonideal("bgamma0") nonideal("bgamma") nonideal("Bdot0") nonideal("Bdot") # the default ## What's the activity coefficient of Na+ at ## 25 degC and 1 bar and an ionic strength of 0.7? sres <- subcrt("Na+", T = 25, IS = 0.7) # Exponentiate to convert log10(gamma) to gamma 10^sres$out[[1]]$loggam # Now use a different method nonideal("bgamma") sres <- subcrt("Na+", T = 25, IS = 0.7) 10^sres$out[[1]]$loggam ## What are activity coefficients of -3, -2, -1, 0, +1, +2, +3 charged species ## as a function of ionic strength and temperature? # First choose the method nonideal("Bdot") # Define the ionic strength and temperature increments IS <- c(0.001, 0.01, 0.1, 0.7) T <- seq(0, 100, 25) # Use species with charges -3, -2, -1, 0, +1, +2, +3 species <- c("PO4-3", "HPO4-2", "H2PO4-", "H3PO4", "Na+", "Ca+2", "Al+3") # Initialize empty output table for T (rows) and charge (columns) gamtab <- matrix(nrow = length(T), ncol = length(species)) rownames(gamtab) <- T colnames(gamtab) <- -3:3 # Make a list of tables to hold the activity coefficients, one for each IS gamma <- rep(list(gamtab), length(IS)) names(gamma) <- IS # Loop over the values of ionic strength for(i in seq_along(IS)) { # Calculate properties of species, including logarithm of activity coefficient sres <- subcrt(species, T = T, IS = IS[i]) # Exponentiate to convert log10(gamma) to gamma, and put the values into the tables for(j in seq_along(species)) gamma[[i]][, j] <- 10^sres$out[[j]]$loggam } # Print the output and make a plot print(gamma) matplot(T, gamma$`0.001`, type = "l") title(main = "activity coefficients of -3, -2, -1, 0, +1, +2, +3 charged species") ## Alberty, 2003 p. 16 Table 1.3: adjusted pKa of acetic acid ## We use the 'IS' argument in subcrt() to calculate adjusted thermodynamic properties # Set ideal.H to FALSE to calculate activity coefficients for the proton # (needed for replication of the values in Alberty's book) nonideal("Alberty") thermo("opt$ideal.H" = FALSE) sres <- subcrt(c("acetate", "H+", "acetic acid"), c(-1, -1, 1), IS=c(0, 0.1, 0.25), T=25, property="logK") # We're within 0.01 of Alberty's pK values Alberty_logK <- c(4.75, 4.54, 4.47) # The maximum (absolute) pairwise difference between x and y max(abs(Alberty_logK - sres$out$logK)) # 0.0072 # Reset option to default thermo("opt$ideal.H" = TRUE) ## An example using IS with affinity(): ## Speciation of phosphate as a function of ionic strength opar <- par(mfrow = c(2, 1)) basis("CHNOPS+") Ts <- c(25, 100) species(c("PO4-3", "HPO4-2", "H2PO4-")) for(T in Ts) { a <- affinity(IS = c(0, 0.14), T = T) e <- equilibrate(a) if(T==25) diagram(e, ylim = c(-3.0, -2.6), legend.x = NULL) else diagram(e, add = TRUE, names = FALSE, col = "red") } title(main="Non-ideality model for phosphate species") dp <- describe.property(c("pH", "T", "T"), c(7, Ts)) legend("topright", lty = c(NA, 1, 1), col = c(NA, "black", "red"), legend = dp) text(0.07, -2.76, expr.species("HPO4-2")) text(0.07, -2.90, expr.species("H2PO4-")) ## Phosphate predominance f(IS,pH) a <- affinity(IS = c(0, 0.14), pH = c(6, 13), T = Ts[1]) d <- diagram(a, fill = NULL) a <- affinity(IS = c(0, 0.14), pH = c(6, 13), T = Ts[2]) d <- diagram(a, add = TRUE, names = FALSE, col = "red") par(opar) ## Activity coefficients for monovalent ions at 700 degC, 10 kbar # After Manning, 2013, Fig. 7 # Here we use the b_gamma equation nonideal("bgamma") IS <- c(0.001, 0.01, 0.1, 1, 2, 2.79) # We're above 5000 bar, so need to use IAPWS-95 or DEW oldwat <- water("DEW") sres <- subcrt("Na+", T = 700, P = 10000, IS = IS) water(oldwat) # Compare the calculated activity coefficient to values from Manning's figure gamma <- 10^sres$out[[1]]$loggam Manning_gamma <- c(0.93, 0.82, 0.65, 0.76, 1.28, 2) gamma - Manning_gamma ## Plot the data and splines used for calculating b_gamma ## (extended term parameter) bgamma(showsplines = "T") bgamma(showsplines = "P") ## A longer example, using nonideal() directly # Alberty, 2003 p. 273-276: activity coefficient (gamma) # as a function of ionic strength and temperature nonideal("Alberty") IS <- seq(0, 0.25, 0.005) T <- c(0, 25, 40) lty <- 1:3 species <- c("H2PO4-", "HADP-2", "HATP-3", "ATP-4") col <- rainbow(4) thermo.plot.new(xlim = range(IS), ylim = c(0, 1), xlab = axis.label("IS"), ylab = "gamma") for(j in 1:3) { # Use subcrt to generate speciesprops speciesprops <- subcrt(species, T = rep(T[j], length(IS)))$out # Use nonideal to calculate loggamma; this also adjusts G, H, S, Cp, # but we don't use them here nonidealprops <- nonideal(species, speciesprops, IS = IS, T = convert(T[j], "K")) for(i in 1:4) lines(IS, 10^(nonidealprops[[i]]$loggam), lty=lty[j], col=col[i]) } t1 <- "Activity coefficient (gamma) of -1,-2,-3,-4 charged species" t2 <- quote("at 0, 25, and 40 "*degree*"C, after Alberty, 2003") mtitle(as.expression(c(t1, t2))) legend("topright", lty=c(NA, 1:3), bty="n", legend=c(as.expression(axis.label("T")), 0, 25, 40)) legend("top", lty=1, col=col, bty="n", legend = as.expression(lapply(species, expr.species))) ## Reset method to default nonideal("Bdot") # or reset()
## Each of the available methods nonideal("Alberty") nonideal("bgamma0") nonideal("bgamma") nonideal("Bdot0") nonideal("Bdot") # the default ## What's the activity coefficient of Na+ at ## 25 degC and 1 bar and an ionic strength of 0.7? sres <- subcrt("Na+", T = 25, IS = 0.7) # Exponentiate to convert log10(gamma) to gamma 10^sres$out[[1]]$loggam # Now use a different method nonideal("bgamma") sres <- subcrt("Na+", T = 25, IS = 0.7) 10^sres$out[[1]]$loggam ## What are activity coefficients of -3, -2, -1, 0, +1, +2, +3 charged species ## as a function of ionic strength and temperature? # First choose the method nonideal("Bdot") # Define the ionic strength and temperature increments IS <- c(0.001, 0.01, 0.1, 0.7) T <- seq(0, 100, 25) # Use species with charges -3, -2, -1, 0, +1, +2, +3 species <- c("PO4-3", "HPO4-2", "H2PO4-", "H3PO4", "Na+", "Ca+2", "Al+3") # Initialize empty output table for T (rows) and charge (columns) gamtab <- matrix(nrow = length(T), ncol = length(species)) rownames(gamtab) <- T colnames(gamtab) <- -3:3 # Make a list of tables to hold the activity coefficients, one for each IS gamma <- rep(list(gamtab), length(IS)) names(gamma) <- IS # Loop over the values of ionic strength for(i in seq_along(IS)) { # Calculate properties of species, including logarithm of activity coefficient sres <- subcrt(species, T = T, IS = IS[i]) # Exponentiate to convert log10(gamma) to gamma, and put the values into the tables for(j in seq_along(species)) gamma[[i]][, j] <- 10^sres$out[[j]]$loggam } # Print the output and make a plot print(gamma) matplot(T, gamma$`0.001`, type = "l") title(main = "activity coefficients of -3, -2, -1, 0, +1, +2, +3 charged species") ## Alberty, 2003 p. 16 Table 1.3: adjusted pKa of acetic acid ## We use the 'IS' argument in subcrt() to calculate adjusted thermodynamic properties # Set ideal.H to FALSE to calculate activity coefficients for the proton # (needed for replication of the values in Alberty's book) nonideal("Alberty") thermo("opt$ideal.H" = FALSE) sres <- subcrt(c("acetate", "H+", "acetic acid"), c(-1, -1, 1), IS=c(0, 0.1, 0.25), T=25, property="logK") # We're within 0.01 of Alberty's pK values Alberty_logK <- c(4.75, 4.54, 4.47) # The maximum (absolute) pairwise difference between x and y max(abs(Alberty_logK - sres$out$logK)) # 0.0072 # Reset option to default thermo("opt$ideal.H" = TRUE) ## An example using IS with affinity(): ## Speciation of phosphate as a function of ionic strength opar <- par(mfrow = c(2, 1)) basis("CHNOPS+") Ts <- c(25, 100) species(c("PO4-3", "HPO4-2", "H2PO4-")) for(T in Ts) { a <- affinity(IS = c(0, 0.14), T = T) e <- equilibrate(a) if(T==25) diagram(e, ylim = c(-3.0, -2.6), legend.x = NULL) else diagram(e, add = TRUE, names = FALSE, col = "red") } title(main="Non-ideality model for phosphate species") dp <- describe.property(c("pH", "T", "T"), c(7, Ts)) legend("topright", lty = c(NA, 1, 1), col = c(NA, "black", "red"), legend = dp) text(0.07, -2.76, expr.species("HPO4-2")) text(0.07, -2.90, expr.species("H2PO4-")) ## Phosphate predominance f(IS,pH) a <- affinity(IS = c(0, 0.14), pH = c(6, 13), T = Ts[1]) d <- diagram(a, fill = NULL) a <- affinity(IS = c(0, 0.14), pH = c(6, 13), T = Ts[2]) d <- diagram(a, add = TRUE, names = FALSE, col = "red") par(opar) ## Activity coefficients for monovalent ions at 700 degC, 10 kbar # After Manning, 2013, Fig. 7 # Here we use the b_gamma equation nonideal("bgamma") IS <- c(0.001, 0.01, 0.1, 1, 2, 2.79) # We're above 5000 bar, so need to use IAPWS-95 or DEW oldwat <- water("DEW") sres <- subcrt("Na+", T = 700, P = 10000, IS = IS) water(oldwat) # Compare the calculated activity coefficient to values from Manning's figure gamma <- 10^sres$out[[1]]$loggam Manning_gamma <- c(0.93, 0.82, 0.65, 0.76, 1.28, 2) gamma - Manning_gamma ## Plot the data and splines used for calculating b_gamma ## (extended term parameter) bgamma(showsplines = "T") bgamma(showsplines = "P") ## A longer example, using nonideal() directly # Alberty, 2003 p. 273-276: activity coefficient (gamma) # as a function of ionic strength and temperature nonideal("Alberty") IS <- seq(0, 0.25, 0.005) T <- c(0, 25, 40) lty <- 1:3 species <- c("H2PO4-", "HADP-2", "HATP-3", "ATP-4") col <- rainbow(4) thermo.plot.new(xlim = range(IS), ylim = c(0, 1), xlab = axis.label("IS"), ylab = "gamma") for(j in 1:3) { # Use subcrt to generate speciesprops speciesprops <- subcrt(species, T = rep(T[j], length(IS)))$out # Use nonideal to calculate loggamma; this also adjusts G, H, S, Cp, # but we don't use them here nonidealprops <- nonideal(species, speciesprops, IS = IS, T = convert(T[j], "K")) for(i in 1:4) lines(IS, 10^(nonidealprops[[i]]$loggam), lty=lty[j], col=col[i]) } t1 <- "Activity coefficient (gamma) of -1,-2,-3,-4 charged species" t2 <- quote("at 0, 25, and 40 "*degree*"C, after Alberty, 2003") mtitle(as.expression(c(t1, t2))) legend("topright", lty=c(NA, 1:3), bty="n", legend=c(as.expression(axis.label("T")), 0, 25, 40)) legend("top", lty=1, col=col, bty="n", legend = as.expression(lapply(species, expr.species))) ## Reset method to default nonideal("Bdot") # or reset()
Use multiple processors for large calculations.
palply(varlist, X, FUN, ...)
palply(varlist, X, FUN, ...)
... |
equivalent to the same argument in |
varlist |
character, names of variables to export using |
X |
vector, argument for |
FUN |
function, argument for |
palply
is a wrapper function to run parallel::parLapply
if length of X
> thermo()$opt$paramin
and multiple cores are available, otherwise it runs lapply
.
Note that parLapply
is called with methods
set to FALSE.
If lots of package startup messages are created when running parallel::makeCluster
(which is called by palply
), it can probably be stopped by adding a test for interactive
sessions around any library
commands in the Rprofile
.
affinity
, equil.boltzmann
and equil.reaction
for functions that use palply
.
Tests are in ‘tests/test-util.program.R’, and a “real world” example is in ‘demo/density.R’.
Protein information, length, chemical formula, thermodynamic properties by group additivity, reaction coefficients of basis species, and metastable equilibrium example calculation.
pinfo(protein, organism=NULL, residue=FALSE, regexp=FALSE) protein.length(protein, organism = NULL) protein.formula(protein, organism = NULL, residue = FALSE) protein.OBIGT(protein, organism = NULL, state=thermo()$opt$state) protein.basis(protein, T = 25, normalize = FALSE) protein.equil(protein, T=25, loga.protein = 0, digits = 4)
pinfo(protein, organism=NULL, residue=FALSE, regexp=FALSE) protein.length(protein, organism = NULL) protein.formula(protein, organism = NULL, residue = FALSE) protein.OBIGT(protein, organism = NULL, state=thermo()$opt$state) protein.basis(protein, T = 25, normalize = FALSE) protein.equil(protein, T=25, loga.protein = 0, digits = 4)
protein |
character, names of proteins; numeric, species index of proteins; data frame; amino acid composition of proteins |
organism |
character, names of organisms |
residue |
logical, return per-residue values (those of the proteins divided by their lengths)? |
regexp |
logical, find matches using regular expressions? |
normalize |
logical, return per-residue values (those of the proteins divided by their lengths)? |
state |
character, physical state |
T |
numeric, temperature in °C |
loga.protein |
numeric, decimal logarithms of reference activities of proteins |
digits |
integer, number of significant digits (see |
For character protein
, pinfo
returns the rownumber(s) of thermo()$protein
that match the protein names.
The names can be supplied in the single protein
argument (with an underscore, denoting protein_organism) or as pairs of protein
s and organism
s.
NA is returned for any unmatched proteins, including those for which no organism
is given or that do not have an underscore in protein
.
Alternatively, if regexp
is TRUE, the protein
argument is used as a pattern (regular expression); rownumbers of all matches of thermo()$protein$protein
to this pattern are returned.
When using regexp
, the organism
can optionally be provided to return only those entries that also match thermo()$protein$organism
.
For numeric protein
, pinfo
returns the corresponding row(s) of thermo()$protein
.
Set residue
to TRUE to return the per-residue composition (i.e. amino acid composition of the protein divided by total number of residues).
For dataframe protein
, pinfo
returns it unchanged, except for possibly the per-residue calculation.
The following functions accept any specification of protein(s) described above for pinfo
:
protein.length
returns the lengths (number of amino acids) of the proteins.
protein.formula
returns a stoichiometrix matrix representing the chemical formulas of the proteins that can be pased to e.g. mass
or ZC
.
The amino acid compositions are multiplied by the output of group.formulas
to generate the result.
protein.OBIGT
calculates the thermodynamic properties and equations-of-state parameters for the completely nonionized proteins using group additivity with parameters taken from Dick et al., 2006 (aqueous proteins) and LaRowe and Dick, 2012 (crystalline proteins and revised aqueous methionine sidechain group).
The return value is a data frame in the same format as thermo()$OBIGT
.
state
indicates the physical state for the parameters used in the calculation (‘aq’ or ‘cr’).
The following functions also depend on an existing definition of the basis species:
protein.basis
calculates the numbers of the basis species (i.e. opposite of the coefficients in the formation reactions) that can be combined to form the composition of each of the proteins.
The basis species must be present in thermo()$basis
, and if ‘H+’ is among the basis species, the ionization states of the proteins are included.
The ionization state of the protein is calculated at the pH defined in thermo()$basis
and at the temperature specified by the T
argument.
If normalize
is TRUE, the coefficients on the basis species are divided by the lengths of the proteins.
protein.equil
produces a series of messages showing step-by-step a calculation of the chemical activities of proteins in metastable equilibrium. For the first protein, it shows the standard Gibbs energies of the reaction to form the nonionized protein from the basis species and of the ionization reaction of the protein (if ‘H+’ is in the basis), then the standard Gibbs energy/RT of the reaction to form the (possibly ionized) protein per residue. The per-residue values of ‘logQstar’ and ‘Astar/RT’ are also shown for the first protein. Equilibrium calculations are then performed, only if more than one protein is specified. This calculation applies the Boltzmann distribution to the calculation of the equilibrium degrees of formation of the residue equivalents of the proteins, then converts them to activities of proteins taking account of loga.protein
and protein length. If the protein
argument is numeric (indicating rownumbers in thermo()$protein
), the values of ‘Astar/RT’ are compared with the output of affinity
, and those of the equilibrium degrees of formation of the residues and the chemical activities of the proteins with the output of diagram
. If the values in any of these tests are are not all.equal
an error is produced indicating a bug.
Dick, J. M., LaRowe, D. E. and Helgeson, H. C. (2006) Temperature, pressure, and electrochemical constraints on protein speciation: Group additivity calculation of the standard molal thermodynamic properties of ionized unfolded proteins. Biogeosciences 3, 311–336. doi:10.5194/bg-3-311-2006
LaRowe, D. E. and Dick, J. M. (2012) Calculation of the standard molal thermodynamic properties of crystalline peptides. Geochim. Cosmochim. Acta 80, 70–91. doi:10.1016/j.gca.2011.11.041
# Search by name in thermo()$protein # These are the same: ip1 == ip2 ip1 <- pinfo("LYSC_CHICK") ip2 <- pinfo("LYSC", "CHICK") # Two organisms with the same protein name ip3 <- pinfo("MYG", c("HORSE", "PHYCA")) # Their amino acid compositions pinfo(ip3) # Their thermodynamic properties by group additivity protein.OBIGT(ip3) # An unknown protein name gives NA ip4 <- pinfo("MYGPHYCA") ## Example for chicken lysozyme C # Index in thermo()$protein ip <- pinfo("LYSC_CHICK") # Amino acid composition pinfo(ip) # Protein length and chemical formula protein.length(ip) protein.formula(ip) # Group additivity for thermodynamic properties and HKF equation-of-state # parameters of non-ionized protein protein.OBIGT(ip) # Calculation of standard thermodynamic properties # (subcrt uses the species name, not ip) subcrt("LYSC_CHICK") # NOTE: subcrt() only shows the properties of the non-ionized # protein, but affinity() uses the properties of the ionized # protein if the basis species have H+ ## These are all the same protein.formula("P53_PIG") protein.formula(pinfo("P53_PIG")) protein.formula(pinfo(pinfo("P53_PIG")))
# Search by name in thermo()$protein # These are the same: ip1 == ip2 ip1 <- pinfo("LYSC_CHICK") ip2 <- pinfo("LYSC", "CHICK") # Two organisms with the same protein name ip3 <- pinfo("MYG", c("HORSE", "PHYCA")) # Their amino acid compositions pinfo(ip3) # Their thermodynamic properties by group additivity protein.OBIGT(ip3) # An unknown protein name gives NA ip4 <- pinfo("MYGPHYCA") ## Example for chicken lysozyme C # Index in thermo()$protein ip <- pinfo("LYSC_CHICK") # Amino acid composition pinfo(ip) # Protein length and chemical formula protein.length(ip) protein.formula(ip) # Group additivity for thermodynamic properties and HKF equation-of-state # parameters of non-ionized protein protein.OBIGT(ip) # Calculation of standard thermodynamic properties # (subcrt uses the species name, not ip) subcrt("LYSC_CHICK") # NOTE: subcrt() only shows the properties of the non-ionized # protein, but affinity() uses the properties of the ionized # protein if the basis species have H+ ## These are all the same protein.formula("P53_PIG") protein.formula(pinfo("P53_PIG")) protein.formula(pinfo(pinfo("P53_PIG")))
Affinity rankings for groups of species.
rank.affinity(aout, groups, percent = TRUE)
rank.affinity(aout, groups, percent = TRUE)
aout |
list, output of |
groups |
named list of indices (integer or numeric) for species in each group |
percent |
return average rank percentage for each group |
The affinities for all species are rank
ed, then the mean ranking for the species in each group is calculated.
The mean rankings of groups are converted to a percentage, or returned as-is if percent
is FALSE.
Note that the calculations are applied to each set of conditions individually (i.e., each grid point in the affinity affinity
calculation).
The average rankings are inserted into the values
element of aout
, and the names of the groups are inserted into the species
element.
The result can be used by diagram
to make line plots or predominance diagrams (the predominance fields correspond to the groups with highest average ranking of affinity).
The reaction coefficients in the species
element of the returned value of aout
are not valid.
Because balancing on a basis species (i.e., dividing by its reaction coefficient) would be incorrect, diagram
enforces balance = 1
so that that average rankings are used without further modification.
demo("rank.affinity")
# Compare Rubisco proteins from three domains datfile <- system.file("extdata/cpetc/rubisco.csv", package = "CHNOSZ") fastafile <- system.file("extdata/protein/rubisco.fasta", package = "CHNOSZ") dat <- read.csv(datfile) aa <- canprot::read_fasta(fastafile) groups <- sapply(c("A", "B", "E"), "==", dat$domain, simplify = FALSE) names(groups) <- c("Archaea", "Bacteria", "Eukaryota") ip <- add.protein(aa, as.residue = TRUE) basis("QEC") aout <- affinity(O2 = c(-74, -66, 100), H2O = c(-4, 4, 100), iprotein = ip) arank <- rank.affinity(aout, groups = groups) nspecies <- sapply(groups, sum) names <- paste0(names(groups), " (", nspecies, ")") diagram(arank, fill = "terrain", font = 2, names = names, format.names = FALSE) title("Average affinity ranking of Rubisco proteins")
# Compare Rubisco proteins from three domains datfile <- system.file("extdata/cpetc/rubisco.csv", package = "CHNOSZ") fastafile <- system.file("extdata/protein/rubisco.fasta", package = "CHNOSZ") dat <- read.csv(datfile) aa <- canprot::read_fasta(fastafile) groups <- sapply(c("A", "B", "E"), "==", dat$domain, simplify = FALSE) names(groups) <- c("Archaea", "Bacteria", "Eukaryota") ip <- add.protein(aa, as.residue = TRUE) basis("QEC") aout <- affinity(O2 = c(-74, -66, 100), H2O = c(-4, 4, 100), iprotein = ip) arank <- rank.affinity(aout, groups = groups) nspecies <- sapply(groups, sum) names <- paste0(names(groups), " (", nspecies, ")") diagram(arank, fill = "terrain", font = 2, names = names, format.names = FALSE) title("Average affinity ranking of Rubisco proteins")
Retrieve species in the database containing one or more chemical elements.
retrieve(elements = NULL, ligands = NULL, state = NULL, T = NULL, P = "Psat", add.charge = TRUE, hide.groups = TRUE)
retrieve(elements = NULL, ligands = NULL, state = NULL, T = NULL, P = "Psat", add.charge = TRUE, hide.groups = TRUE)
elements |
character, combination of elements, or list, elements in a chemical system |
ligands |
character, elements present in any ligands |
state |
character, filter the result on these state(s). |
T |
numeric, temperature where ΔG° of species must be not NA |
P |
numeric, pressure where ΔG° of species must be not NA |
add.charge |
logical, add charge to the system? |
hide.groups |
logical, exclude groups from the result? |
This function retrieves the species in the thermodynamic database (see thermo
) that have the indicated elements
.
A character value of elements
is interpreted as a combination of one or more elements that must be present in each species.
A list value of elements
is used to specify a chemical system – the species must contain one or more of the indicated elements, but no other elements.
ligands
, if present, gives the elements that may be present in any ligands; this can be used to retrieve all species in a system bearing the elements
(usually a single metal).
The result includes charged species if add.charge
is TRUE (the default) or the user supplies the “element” of charge (‘Z’).
Results can be filtered on physical state by setting the state
argument.
Groups used in group-additivity calculations, which have names with square brackets (e.g. [-CH2-]), are excluded unless hide.groups
is FALSE.
A special argument value ‘all’ can be used to retrieve all species in the thermodynamic database, including filtering on state and hiding of the groups.
The return value is a named integer vector giving the species index (i.e. rownumber(s) of thermo()$OBIGT
) with names corresponding to the chemical formulas of the species.
If the electron is in the result, its name (‘e-’) is used instead of its chemical formula (‘(Z-1)’).
An empty (length 0) integer value is returned if no elements
are specified or no species are retrieved.
Set T
(and optionally P
) to require that species have non-NA values of ΔG° at this temperature and pressure.
These values are passed to subcrt
and therefore have the units set in T.units
and P.units
.
To speed up operation, the function uses a precalculated stoichiometric matrix for the default database, which is loaded with the package (see thermo
).
If the function detects a change to any chemical formulas in the database, it updates the stoichiometric matrix using i2A
.
info
for basic database searches; anintro for a diagram made with retrieve
d species in the Mn-O-H system.
# Species index of Ti-bearing minerals retrieve("Ti") # Thermodynamic data for those minerals info(retrieve("Ti")) # All species that have Au retrieve("Au") # All species that have both Au and Cl retrieve(c("Au", "Cl")) # Au-Cl system: species that have Au and/or Cl, # including charged species, but no other elements retrieve(list("Au", "Cl")) # All Au-bearing species in the Au-Cl system retrieve("Au", "Cl") # All uncharged Au-bearing species in the Au-Cl system retrieve("Au", "Cl", add.charge = FALSE) # Minerals in the system SiO2-MgO-CaO-CO2 retrieve(list("Si", "Mg", "Ca", "C", "O"), state = "cr")
# Species index of Ti-bearing minerals retrieve("Ti") # Thermodynamic data for those minerals info(retrieve("Ti")) # All species that have Au retrieve("Au") # All species that have both Au and Cl retrieve(c("Au", "Cl")) # Au-Cl system: species that have Au and/or Cl, # including charged species, but no other elements retrieve(list("Au", "Cl")) # All Au-bearing species in the Au-Cl system retrieve("Au", "Cl") # All uncharged Au-bearing species in the Au-Cl system retrieve("Au", "Cl", add.charge = FALSE) # Minerals in the system SiO2-MgO-CaO-CO2 retrieve(list("Si", "Mg", "Ca", "C", "O"), state = "cr")
Calculate chemical activities of aqueous species in equilibrium with a mineral or gas.
solubility(iaq, ..., in.terms.of = NULL, dissociate = FALSE, find.IS = FALSE)
solubility(iaq, ..., in.terms.of = NULL, dissociate = FALSE, find.IS = FALSE)
iaq |
character (names) or numeric (species indices) of aqueous species |
... |
|
in.terms.of |
character, express the total solubility in terms of moles of this species |
dissociate |
logical, does the mineral undergo a dissociation reaction? |
find.IS |
logical, find the equilibrium ionic strength by iteration? |
solubility
calculates the activities of aqueous species in equilibrium with one or more minerals or gases.
The minerals or gases should be loaded as the formed species
, and the aqueous species (including ions and/or neutral complexes) that can be produced by dissolution should be listed in the iaq
argument.
The definitions of plotting variables should be provided in ...
, which are passed as arguments to affinity
, or to mosaic
if the first one is named bases
.
It must be possible to obtain a valid set of basis species by substituting each of the minerals or gases in the first position of the current basis
defintion, and all of the aqueous species must include that basis species in their formation reactions.
(This essentially means that all minerals, gases and aqueous species must share a common element, which is what the reactions are balanced on.)
For a single mineral or gas, the output of solubility
can be used by diagram
with type = NULL
(the default) to plot the activities of the aqueous species or with type = "loga.balance"
to plot the sum of activities of aqueous species, which corresponds to the solubility of the mineral or gas.
This value corresponds to the total extent of dissolution of the mineral or gas; in.terms.of
can be used to express this value in terms of another species or element.
For example, for dissolution of gaseous S2, in.terms.of = "S"
gives the total amount of S in solution, which is twice the amount of S2 dissolved.
Likewise, the solubility of corundum (Al2O3) can be expressed in terms of the moles of Al+3 in solution (see the vignette anintro).
For multiple minerals, the function calculates the solubilities for each of the minerals separately; these are stored in the loga.equil
element of the output.
The overall minimum solubility among all the minerals at each point is stored in loga.balance
.
This corresponds to the total activity of dissolved species in equilibrium with the most stable mineral.
In contrast to the situation for a single mineral or gas, diagram
by default plots loga.balance
; type = "loga.equil"
can be used to plot the solubilities for the individual minerals or gases.
For compatibility with previous versions of the function, the iaq
argument can be the output of affinity
or mosaic
for aqueous species.
The examples for ionic strength and dissociation reactions were designed for this calling style.
In this case the (single) mineral or gas being dissolved is taken from the current basis
species.
Usually, the basis species should be set up so that the first basis species represents the substance being dissolved (a mineral such as CaCO3 or gas such as CO2).
This is treated as the conserved basis species, so it must be present in all of the formation reactions of the aqueous species.
The species
should be defined to represent one set of aqueous species (including ions and/or neutral complexes) formed in solution, all involving the conserved basis species.
For a dissociation reaction, the second basis species should be used to represent the counterion (cation or anion).
Other variables (pH, ionic strength, activities of other basis species) should be defined in the call to affinity
to make iaq
.
The function perfoms some additional steps to calculate the solubility of something that dissociates (not just dissolves). For example, the dissolution of calcite (CaCO3), involves the release of both calcium ions and different forms of carbonate in solution, depending on the pH. The equilibrium calculation must take account of the total activity of the shared ion (Ca+2), which is unknown at the start of the calculation. The solution is found by recalculating the affinities, essentially working backward from the assumption that the dissociation didn't occur. The resulting activities correspond to equilibrium considering the system-wide activity of Ca+2.
A not recommended alternative is to set dissociate
to a numeric value corresponding to the number of dissociated species (i.e. 2 for a 1:1 electrolyte).
This setting indicates to calculate activities on a per-reaction basis, where each reaction has its own (independent) activity of Ca+2.
That does not give a complete equilibrium in the system, but may be required to reproduce some published diagrams (see comment in the calcite example of demo("solubility")
).
Set find.IS
to TRUE to determine the final ionic strength due to dissolution of a substance in pure water.
This works by calculating the ionic strength from the amounts of aqueous species formed, then re-running affinity
with the calculated IS
value.
Note that for dissociation reactions, the ionic strength is calculated from both the ions present in the species definition and the counter ion, which should be the second basis species.
The calculation is iterated until the ionic strength deviation at every point is lower than a preset tolerance (1e-4).
Alternatively, speciation of counterions (e.g. ionized forms of carbonate or sulfate) can also be performed by using the mosaic
function instead of affinity
; this is used in the second example below.
This function has not been tested for systems that may form dimers or higher-order complexes (such as Au2S22-). Except for relatively simple systems, even after careful refinement, the results from CHNOSZ, which considers chemical activities as the independent variables, will not match the results from speciation-solubility (or Gibbs energy minimization) codes, where the system is defined by its bulk composition.
retrieve
provides a way to list all of the aqueous species in the database that have the specified elements.
demo("solubility")
shows solubilities of CO2 and calcite calculated as a function of pH and T; note that for calcite, the dissociate
argument is set to TRUE.
demo("gold")
shows solubility calculations for Au in aqueous solutions with hydroxide, chloride, and hydrosulfide complexes.
Solubility calculations for multiple minerals are used for generating isosolubility (aka. equisolubility) lines in demo("Pourbaix")
and demo("minsol")
.
The latter demo combines the calculation of solubilities with a mosaic
calculation to account for the speciation of aqueous sulfur.
Whereas solubility
yields a stable equilibrium condition (the affinities of formation reactions of aqueous species are zero), equilibrate
generates metastable equilibrium (the affinities of formation reactions are equal to each other, but not necessarily zero).
## EXAMPLE 1 # Calculate solubility of a single substance: # Gaseous SO2 with a given fugacity # Define basis species (any S-bearing basis species should be first) basis(c("sulfur", "oxygen", "H2O", "H+")) basis("pH", 6) # Load the substances (minerals or gases) to be dissolved species("sulfur dioxide", -20) # List the formed aqueous species # We can use retrieve() to identify all the possible aqueous species iaq <- retrieve("S", c("O", "H"), "aq") # Place arguments for affinity() after the first argument of solubility() s1 <- solubility(iaq, O2 = c(-56, -46), T = 125, in.terms.of = "S") # Calculate overall solubility for multiple substances: # Gaseous S2 and SO2 with a given fugacity basis(c("sulfur", "oxygen", "H2O", "H+")) basis("pH", 6) species(c("S2", "sulfur dioxide"), -20) s2 <- solubility(iaq, O2 = c(-56, -46), T = 125, in.terms.of = "S") # Make expressions for legends S_ <- expr.species("SO2", "gas", -20, TRUE) pH_ <- quote(pH == 6) T_ <- lT(125) lexpr <- lex(S_, pH_, T_) # Make diagrams from the results of solubility calculations layout(matrix(c(1, 3, 2, 3), nrow = 2)) # Logarithm of activity of aqueous species in equilibrium with SO2(gas) diagram(s1, ylim = c(-15, 0)) diagram(s1, type = "loga.balance", col = 3, lwd = 3, add = TRUE) legend("topright", legend = lexpr, bty = "n") # Logarithm of concentration (parts per million) of aqueous species sppm <- convert(s1, "logppm") diagram(sppm, ylim = c(-10, 5)) diagram(sppm, type = "loga.balance", col = 3, lwd = 3, add = TRUE) legend("topright", legend = lexpr, bty = "n") par(xpd = NA) text(-58, 6.5, paste("Solubility of gaseous SO2 (green line) is", "sum of concentrations of aqueous species"), cex = 1.2, font = 2) par(xpd = FALSE) # Show overall (minimum) solubility of multiple gases diagram(s2, col = 4, lwd = 3) # Show solubilities of individual gases names <- info(species()$ispecies)$formula diagram(s2, type = "loga.equil", names = names, add = TRUE) title("Minimum solubility (blue line) corresponds to the most stable gas") layout(matrix(1)) ## EXAMPLE 2 ## Two ways to calculate pH-dependent solubility of calcite ## with ionic strength determination ## Method 1: CO2 and carbonate species as formed species basis(c("CO2", "Ca+2", "H2O", "O2", "H+")) species("calcite") iaq <- info(c("CO2", "HCO3-", "CO3-2")) # Ionic strength calculations don't converge below around pH = 3 sa0 <- solubility(iaq, pH = c(4, 14), dissociate = TRUE) saI <- solubility(iaq, pH = c(4, 14), dissociate = TRUE, find.IS = TRUE) ## Method 2: CO2 and carbonate species as basis species basis(c("Ca+2", "CO2", "H2O", "O2", "H+")) species("calcite") iaq <- info("Ca+2") bases <- c("CO2", "HCO3-", "CO3-2") sm0 <- solubility(iaq, bases = bases, pH = c(4, 14), dissociate = TRUE) smI <- solubility(iaq, bases = bases, pH = c(4, 14), dissociate = TRUE, find.IS = TRUE) ## Plot the results plot(0, 0, xlab="pH", ylab="solubility, log mol", xlim = c(4, 14), ylim = c(-5, 2)) # Method 1 with/without ionic strength lines(saI$vals[[1]], saI$loga.balance, lwd = 5, col = "lightblue") lines(sa0$vals[[1]], sa0$loga.balance, lwd = 5, col = "pink") # Method 2 with/without ionic strength lines(smI$vals[[1]], smI$loga.balance, lty = 2) lines(sm0$vals[[1]], sm0$loga.balance, lty = 2) legend("topright", c("I = 0", "I = calculated", "mosaic method"), col = c("pink", "lightblue", "black"), lwd = c(5, 5, 1), lty = c(1, 1, 2)) title(main = "Solubility of calcite: Ionic strength and mosaic method") # The two methods give nearly equivalent results stopifnot(all.equal(sa0$loga.balance, sm0$loga.balance)) stopifnot(all.equal(saI$loga.balance, smI$loga.balance, tolerance = 0.003)) ## NOTE: the second method (using mosaic) is slower, but is ## more flexible; e.g. complexes with Ca+2 could be included
## EXAMPLE 1 # Calculate solubility of a single substance: # Gaseous SO2 with a given fugacity # Define basis species (any S-bearing basis species should be first) basis(c("sulfur", "oxygen", "H2O", "H+")) basis("pH", 6) # Load the substances (minerals or gases) to be dissolved species("sulfur dioxide", -20) # List the formed aqueous species # We can use retrieve() to identify all the possible aqueous species iaq <- retrieve("S", c("O", "H"), "aq") # Place arguments for affinity() after the first argument of solubility() s1 <- solubility(iaq, O2 = c(-56, -46), T = 125, in.terms.of = "S") # Calculate overall solubility for multiple substances: # Gaseous S2 and SO2 with a given fugacity basis(c("sulfur", "oxygen", "H2O", "H+")) basis("pH", 6) species(c("S2", "sulfur dioxide"), -20) s2 <- solubility(iaq, O2 = c(-56, -46), T = 125, in.terms.of = "S") # Make expressions for legends S_ <- expr.species("SO2", "gas", -20, TRUE) pH_ <- quote(pH == 6) T_ <- lT(125) lexpr <- lex(S_, pH_, T_) # Make diagrams from the results of solubility calculations layout(matrix(c(1, 3, 2, 3), nrow = 2)) # Logarithm of activity of aqueous species in equilibrium with SO2(gas) diagram(s1, ylim = c(-15, 0)) diagram(s1, type = "loga.balance", col = 3, lwd = 3, add = TRUE) legend("topright", legend = lexpr, bty = "n") # Logarithm of concentration (parts per million) of aqueous species sppm <- convert(s1, "logppm") diagram(sppm, ylim = c(-10, 5)) diagram(sppm, type = "loga.balance", col = 3, lwd = 3, add = TRUE) legend("topright", legend = lexpr, bty = "n") par(xpd = NA) text(-58, 6.5, paste("Solubility of gaseous SO2 (green line) is", "sum of concentrations of aqueous species"), cex = 1.2, font = 2) par(xpd = FALSE) # Show overall (minimum) solubility of multiple gases diagram(s2, col = 4, lwd = 3) # Show solubilities of individual gases names <- info(species()$ispecies)$formula diagram(s2, type = "loga.equil", names = names, add = TRUE) title("Minimum solubility (blue line) corresponds to the most stable gas") layout(matrix(1)) ## EXAMPLE 2 ## Two ways to calculate pH-dependent solubility of calcite ## with ionic strength determination ## Method 1: CO2 and carbonate species as formed species basis(c("CO2", "Ca+2", "H2O", "O2", "H+")) species("calcite") iaq <- info(c("CO2", "HCO3-", "CO3-2")) # Ionic strength calculations don't converge below around pH = 3 sa0 <- solubility(iaq, pH = c(4, 14), dissociate = TRUE) saI <- solubility(iaq, pH = c(4, 14), dissociate = TRUE, find.IS = TRUE) ## Method 2: CO2 and carbonate species as basis species basis(c("Ca+2", "CO2", "H2O", "O2", "H+")) species("calcite") iaq <- info("Ca+2") bases <- c("CO2", "HCO3-", "CO3-2") sm0 <- solubility(iaq, bases = bases, pH = c(4, 14), dissociate = TRUE) smI <- solubility(iaq, bases = bases, pH = c(4, 14), dissociate = TRUE, find.IS = TRUE) ## Plot the results plot(0, 0, xlab="pH", ylab="solubility, log mol", xlim = c(4, 14), ylim = c(-5, 2)) # Method 1 with/without ionic strength lines(saI$vals[[1]], saI$loga.balance, lwd = 5, col = "lightblue") lines(sa0$vals[[1]], sa0$loga.balance, lwd = 5, col = "pink") # Method 2 with/without ionic strength lines(smI$vals[[1]], smI$loga.balance, lty = 2) lines(sm0$vals[[1]], sm0$loga.balance, lty = 2) legend("topright", c("I = 0", "I = calculated", "mosaic method"), col = c("pink", "lightblue", "black"), lwd = c(5, 5, 1), lty = c(1, 1, 2)) title(main = "Solubility of calcite: Ionic strength and mosaic method") # The two methods give nearly equivalent results stopifnot(all.equal(sa0$loga.balance, sm0$loga.balance)) stopifnot(all.equal(saI$loga.balance, smI$loga.balance, tolerance = 0.003)) ## NOTE: the second method (using mosaic) is slower, but is ## more flexible; e.g. complexes with Ca+2 could be included
Define the species of interest in a system; modify their physical states and logarithms of activities.
species(species = NULL, state = NULL, delete = FALSE, add = FALSE, index.return = FALSE)
species(species = NULL, state = NULL, delete = FALSE, add = FALSE, index.return = FALSE)
species |
character, names or formulas of species to add to the species definition; numeric, rownumbers of species to modify or delete |
state |
character, physical states; numeric, logarithms of activities or fugacities |
delete |
logical, delete the species identified by numeric values of |
add |
logical, delete a previous species definition instead of adding to it? |
index.return |
logical, return the affected rownumbers of |
After defining the basis
species of your system you can use species
to identify the species of interest.
A species is uniquely identified by a combination of a name
and state
, which are columns of the thermodynamic database in thermo()$OBIGT
.
For each match of species
to the name, formula, or abbreviation of a species, and of state
to the state (‘aq’, ‘cr’, ‘gas’, ‘liq’), the species is added to the current species definition in thermo()$species
.
The state
argument can be omitted, in which case the first matching species in any state is added (in many cases, this means the aqueous species).
If there are multiple matches for a species, the one that is in the state given by thermo()$opt$state
is chosen, otherwise the matching (or 'th matching duplicate) species is used.
Note that the
state
s of species representing phases of minerals that undergo polymorphic transitions are coded as ‘cr’ (lowest-T phase), ‘cr2’, ‘cr3’, ...
(phases with increasing temperature).
If state
is ‘cr’ when one of these minerals is matched, all the polymorphs are added.
The data frame in thermo()$species
holds the species names and indices as well as the stoichiometric reaction coefficients for the formation reaction from the basis species and the logarithms of activities or fugacities that are used by affinity
.
The default values for logarithms of activities are -3 for aqueous (‘aq’) species and 0 for others.
To modify the logarithms of activities of species (logarithms of fugacities for gases) provide one or more numeric values of species
referring to the rownumbers of the species dataframe, or species
NULL, to modify all currently defined species.
The values in state
, if numeric, are interpreted as the logarithms of activities, or if character are interpreted as new states for the species.
If species
is numeric and delete
is TRUE
, these species are deleted from the dataframe; if the only argument is delete
and it is TRUE
, all the species are removed.
By default, when identifying new species, any previous species definition is removed.
Set add
to TRUE to add species to an existing definition.
With no arguments or when adding species, species
returns the value of thermo()$species
, unless index.return
is TRUE, when the function returns the rownumbers of thermo()$species
having the new species.
With ‘delete=TRUE’, the value is the definition that existed prior the deletion; with ‘delete=TRUE’ and ‘species’ not NULL, the number of species remaining after the selected ones have been deleted, or NULL
if no species remain.
Use info
to search the thermodynamic database without adding species to the system. basis
is a prerequisite for species
.
# Set up the basis species basis("CHNOS") # Define some aqueous species species(c("CO2", "NH3")) # Add some gases species(c("CO2", "NH3"), "gas", add = TRUE) # Delete the aqueous species species(1:2, delete = TRUE) # Modify the "logact" value # (log10 of activity for aqueous species; # log10 of fugacity for gases) species(1:2, c(-2, -5)) # Change the state to aqueous species(1:2, "aq") # Load a new species definition (deletes the old one first) species(c("glycine", "alanine")) # Delete all the species species(delete = TRUE) # Changing the elements in the basis definition # causes species to be deleted basis(c("CaO", "CO2", "H2O", "SiO2", "MgO", "O2")) species(c("dolomite", "quartz", "calcite", "forsterite")) basis(c("CO2", "H2O", "O2")) species() # NULL
# Set up the basis species basis("CHNOS") # Define some aqueous species species(c("CO2", "NH3")) # Add some gases species(c("CO2", "NH3"), "gas", add = TRUE) # Delete the aqueous species species(1:2, delete = TRUE) # Modify the "logact" value # (log10 of activity for aqueous species; # log10 of fugacity for gases) species(1:2, c(-2, -5)) # Change the state to aqueous species(1:2, "aq") # Load a new species definition (deletes the old one first) species(c("glycine", "alanine")) # Delete all the species species(delete = TRUE) # Changing the elements in the basis definition # causes species to be deleted basis(c("CaO", "CO2", "H2O", "SiO2", "MgO", "O2")) species(c("dolomite", "quartz", "calcite", "forsterite")) basis(c("CO2", "H2O", "O2")) species() # NULL
Create a stacked mosaic diagram, where the species formed in the first layer become the basis species for the species formed in the second layer. The species in each layer are usually minerals with different metals; any bimetallic species are added to the second layer.
stack_mosaic(bases, species1, species2, species12, names = NULL, col = list(4, 3, 6), col.names = list(4, 3, 6), fill = NULL, dx = list(0, 0, 0), dy = list(0, 0, 0), srt = list(0, 0, 0), lwd = list(1, 1, 1), lty = list(1, 1, 1), loga_aq = NULL, plot.it = TRUE, ...)
stack_mosaic(bases, species1, species2, species12, names = NULL, col = list(4, 3, 6), col.names = list(4, 3, 6), fill = NULL, dx = list(0, 0, 0), dy = list(0, 0, 0), srt = list(0, 0, 0), lwd = list(1, 1, 1), lty = list(1, 1, 1), loga_aq = NULL, plot.it = TRUE, ...)
bases |
basis species to be changed for each layer (commonly S-bearing aqueous species) |
species1 |
species (minerals and/or aqueous species) with metal 1 |
species2 |
species with metal 2 |
species12 |
bimetallic species |
names |
character, species names (or chemical formulas) for labeling fields |
col |
line color |
col.names |
text color |
fill |
field color |
dx |
label x-offset |
dy |
label y-offset |
srt |
label rotation |
lwd |
line width |
lty |
line type |
loga_aq |
numeric, activity of aqueous species |
plot.it |
make plots? |
... |
stack_mosaic
creates a stacked mosaic diagram following steps that are described in detail in the vignette multi-metal.
Briefly, the first layer of the diagram is made by speciating the species in bases
across the diagram to form the first set of species in species1
.
Then, both bases
and species1
(the stable species at each point on the diagram) are used to form the second set of species, including those in both species2
and species12
.
Note that basis
has aqueous S species in the examples provided, and species1
consists of minerals and/or aqueous species with a single metal (e.g. Fe).
species2
has minerals and/or aqueous species with a second metal (e.g. Cu), and species12
has bimetallic minerals.
For “mixed” diagrams (where species1
or species2
has both minerals and aqueous species), use loga_aq
to set the logarithms of activities of aqueous species.
Here, only a single value of loga_aq
is needed, unlike in mosaic
, where a value for each set of basis species is required.
The plot parameters col
, col.names
, fill
, dx
, dy
, srt
, lwd
, and lty
should be length-3 lists (not vectors).
The values of elements 1–3 of the list are recycled to the number of species in species1
, species2
, and species12
, respectively.
For fill
, the default is to use no fill except for species12
, where the fill color is taken from col.names
with added transparency added using adjustcolor
.
A list of length two containing the output of each of the diagram
calls use to make the diagram.
The bimetallic species in species12
are shown as part of the second layer, although their formation is sensitive to the presence of stable species in the first layer.
It follows that changing the order of layers (i.e., swapping species1
and species2
) can affect the depiction of mineral assemblages that have species12
.
It is likely that only one of the alternatives is thermodynamically correct, but currently there is no check to determine which one it is.
# Define temperature (degrees C), pressure (bar), pH and logfO2 ranges T <- 200 P <- "Psat" res <- 200 pH <- c(0, 14, res) O2 <- c(-48, -33, res) # Define system: Fe-Cu-O-S-Cl # NOTE: the basis species must include the first species listed # in each of bases, species1, and species2 below basis(c("pyrite", "Cu", "Cl-", "H2S", "H2O", "oxygen", "H+")) basis("H2S", -2) # Calculate solution composition for 1 mol/kg NaCl NaCl <- NaCl(T = T, P = P, m_tot = 1) basis("Cl-", log10(NaCl$m_Cl)) # Define arguments for stack_mosaic: Speciate aqueous sulfur bases <- c("H2S", "HS-", "HSO4-", "SO4-2") # Calculate stabilities of Fe-bearing minerals first species1 <- c("pyrite", "pyrrhotite", "magnetite", "hematite") # Calculate stabilities of Cu-bearing and FeCu-bearing minerals second species2 <- c("copper", "cuprite", "tenorite", "chalcocite", "covellite") species12 <- c("chalcopyrite", "bornite") # Use abbreviations for Fe-bearing minerals and formulas for Cu-bearing minerals names1 <- c("Py", "Po", "Mag", "Hem") names2 <- info(info(species2))$formula names12 <- info(info(species12))$formula names <- list(names1, names2, names12) # Adjust x-position for one species (chalcocite, Cu2S) dx <- list(c(0, 0, 0, 0), c(0, 0, 0, 1, 0), c(0, 0)) # Use thick dashed lines for the bimetallic species lwd <- list(1, 1, 2) lty <- list(1, 1, 2) # Make the diagram stack_mosaic(bases, species1, species2, species12, names = names, dx = dx, lwd = lwd, lty = lty, pH = pH, O2 = O2, T = T, P = P, IS = NaCl$IS) # Add legend and title lTP <- lex(lTP(T, P)) db <- describe.basis(c(3:4)) legend("topright", c(lTP, db), bg = "white") title("Fe-Cu-S-O-H-Cl", font.main = 1)
# Define temperature (degrees C), pressure (bar), pH and logfO2 ranges T <- 200 P <- "Psat" res <- 200 pH <- c(0, 14, res) O2 <- c(-48, -33, res) # Define system: Fe-Cu-O-S-Cl # NOTE: the basis species must include the first species listed # in each of bases, species1, and species2 below basis(c("pyrite", "Cu", "Cl-", "H2S", "H2O", "oxygen", "H+")) basis("H2S", -2) # Calculate solution composition for 1 mol/kg NaCl NaCl <- NaCl(T = T, P = P, m_tot = 1) basis("Cl-", log10(NaCl$m_Cl)) # Define arguments for stack_mosaic: Speciate aqueous sulfur bases <- c("H2S", "HS-", "HSO4-", "SO4-2") # Calculate stabilities of Fe-bearing minerals first species1 <- c("pyrite", "pyrrhotite", "magnetite", "hematite") # Calculate stabilities of Cu-bearing and FeCu-bearing minerals second species2 <- c("copper", "cuprite", "tenorite", "chalcocite", "covellite") species12 <- c("chalcopyrite", "bornite") # Use abbreviations for Fe-bearing minerals and formulas for Cu-bearing minerals names1 <- c("Py", "Po", "Mag", "Hem") names2 <- info(info(species2))$formula names12 <- info(info(species12))$formula names <- list(names1, names2, names12) # Adjust x-position for one species (chalcocite, Cu2S) dx <- list(c(0, 0, 0, 0), c(0, 0, 0, 1, 0), c(0, 0)) # Use thick dashed lines for the bimetallic species lwd <- list(1, 1, 2) lty <- list(1, 1, 2) # Make the diagram stack_mosaic(bases, species1, species2, species12, names = names, dx = dx, lwd = lwd, lty = lty, pH = pH, O2 = O2, T = T, P = P, IS = NaCl$IS) # Add legend and title lTP <- lex(lTP(T, P)) db <- describe.basis(c(3:4)) legend("topright", c(lTP, db), bg = "white") title("Fe-Cu-S-O-H-Cl", font.main = 1)
Calculate the standard molal thermodynamic properties of one or more species or a reaction between species as a function of temperature and pressure.
subcrt(species, coeff = 1, state = NULL, property = c("logK","G","H","S","V","Cp"), T = seq(273.15,623.15,25), P = "Psat", grid = NULL, convert = TRUE, exceed.Ttr = FALSE, exceed.rhomin = FALSE, logact = NULL, autobalance = TRUE, use.polymorphs = TRUE, IS = 0)
subcrt(species, coeff = 1, state = NULL, property = c("logK","G","H","S","V","Cp"), T = seq(273.15,623.15,25), P = "Psat", grid = NULL, convert = TRUE, exceed.Ttr = FALSE, exceed.rhomin = FALSE, logact = NULL, autobalance = TRUE, use.polymorphs = TRUE, IS = 0)
species |
character, name or formula of species, or numeric, rownumber of species in |
coeff |
numeric, reaction coefficients on species |
state |
character, state(s) of species |
property |
character, property(s) to calculate |
T |
numeric, temperature(s) of the calculation |
P |
numeric, pressure(s) of the calculation, or character, ‘Psat’ |
grid |
character, type of |
exceed.Ttr |
logical, calculate Gibbs energies of mineral phases and other species beyond their transition temperatures? |
exceed.rhomin |
logical, return properties of species in the HKF model below 0.35 g cm-3? |
logact |
numeric, logarithms of activities of species in reaction |
convert |
logical, are units of T, P, and energy settable by the user (default) (see |
autobalance |
logical, attempt to automatically balance reaction with basis species? |
use.polymorphs |
logical, automatically identify available polymorphs in OBIGT and use the stable one at each value of |
IS |
numeric, ionic strength(s) at which to calculate adjusted molal properties, mol kg |
subcrt
calculates the standard molal thermodynamic properties of species and reactions as a function of temperature and pressure.
For each of the species
(a formula or name), optionally identified in a given state
, the standard molal thermodynamic properties and equations-of-state parameters are retrieved via info
(except for H2O liquid).
The standard molal properties of the species are computed using the thermodynamic model
given for each species (see thermo
).
This function also calculates the thermodynamic properties of reactions by summing those of the respective species.
This functionality is inspired the SUPCRT92 package (Johnson et al., 1992).
T
and P
denote the temperature and pressure for the calculations.
The only valid non-numeric value is ‘Psat’ for P
, which is the default (see water
).
For calculations below 273.16 K, P
set to 1, as PSAT is not defined at subzero (°C) temperatures.
At temperatures above the critical point of water, P
must be set to a numeric value; unless exceed.rhomin
is TRUE, this should correspond to a fluid density ≥ 0.35 g cm-3.
Argument grid
if present can be one of T
or P
to perform the computation of a T
P
or P
T
grid.
The property
s to be calculated can be one or more of those shown below:
rho |
Density of water | g cm |
logK |
Logarithm of equilibrium constant | dimensionless |
G |
Gibbs energy | (cal | J) mol |
H |
Enthalpy | (cal | J) mol |
S |
Entropy | (cal | J) K mol |
V |
Volume | cm mol |
Cp |
Heat capacity | (cal | J) K mol |
E |
Exapansibility | cm K |
kT |
Isothermal compressibility | cm bar |
If convert
is TRUE
(the default), the input values of T
and P
are interpreted to have the units given by T.units
and P.units
(default: °C and bar), and the output values of G
, H
, S
and Cp
are based on the units given in E.units
(default: Joules).
If convert
is FALSE
, the user units (T.units
, P.units
, and E.units
) are ignored, and T
and P
are taken to be in Kelvin and bar, and the returned values of G
, H
, S
and Cp
are in Joules.
A chemical reaction is defined if coeff
is given.
In this mode the standard molal properties of species are summed according to the stoichiometric coeff
icients, where negative values denote reactants.
An unbalanced reaction is signalled if the amount of any element on the reactant and product sides differs by more than 1e-7; in this case, subcrt
prints the missing composition needed to balance the reaction and produces a warning but computes a result anyway.
Alternatively, if autobalance
is TRUE
, the basis
species of a system were previously defined, and all elements in the reaction are represented by the basis species, an unbalanced reaction given in the arguments to subcrt
will be balanced automatically.
The auto balancing doesn't change the reaction coefficients of any species in the reaction that are not among the basis species.
If logact
is provided, the chemical affinities of reactions are calculated.
logact
indicates the logarithms of activities (fugacities for gases) of species in the reaction; if there are fewer values of logact
than number of species those values are repeated as necessary.
If the reaction was unbalanced to start, the logarithms of activities of any basis species added to the reaction are taken from the current definition of the basis
species.
Columns appended to the output are logQ
for the log10 of the activity product of the reaction, and A
for the chemical affinity, in the units set by E.units
.
Note that affinity
provides related functionality but is geared toward the properties of formation reactions of species from the basis species and can be performed in more dimensions.
Calculations of chemical affinity in subcrt
can be performed for any reaction of interest; however, they are currently limited to constant values of the logarithms of activities of species in the reactions, and hence of logQ
, across the computational range.
If IS
is set to a single value other than zero, nonideal
is used to calculate the adjusted properties (G
, H
, S
and Cp
) of charged aqueous species at the given ionic strength.
To perform calculations at a single P
and T
and for multiple values of ionic strength, supply these values in IS
.
Calculations can also be performed on a P
-IS
, T
-IS
or P,T
-IS
grid.
Values of logK
of reactions calculated for IS
not equal to zero are consistent with the adjusted Gibbs energies of the charged aqueous species.
If thermo()$opt$varP
is TRUE
, standard Gibbs energies of gases will be converted from a standard state at 1 bar (as used in SUPCRT) to a variable pressure standard state (see chapter 12 in Anderson and Crerar, 1993).
This is useful for constructing e.g. boiling curves for organic compounds.
A list of length two or three. If the properties of a reaction were calculated, the first element of the list (named ‘reaction’) contains a dataframe with the reaction parameters; the second element, named ‘out’, is a dataframe containing the calculated properties. Otherwise, the properties of species (not reactions) are returned: the first element, named ‘species’, contains a dataframe with the species identification; the second element, named ‘out’, is itself a list, each element of which is a dataframe of properties for a given species. If minerals with polymorphic transitions are present, a third element (a dataframe) in the list indicates for all such minerals the stable phase at each grid point.
Although SUPCRT92 prohibits calculations above 350 °C at PSAT (“beyond range of applicability of aqueous species equations”), CHNOSZ does not impose this limitation, and allows calculations up to the critical temperature (373.917 °C) at PSAT.
Interpret calculations between 350 °C and the critical temperature at PSAT at your own risk.
The discontinuity in the value of log K at PSAT that is apparent in demo("NaCl")
demonstrates one unexpected result.
NA
s are produced for calculations at ‘Psat’ when the temperature exceeds the critical temperature of H2O.
In addition, properties of species using the revised HKF equations are set to NA
wherever the density of H2O < 0.35 g/cm3 (threshold just above the critical isochore; Johnson et al., 1992).
Both of these situations produce warnings, which are stored in the ‘warnings’ element of the return value.
NA
s are also output if the T, P conditions are otherwise beyond the capabilities of the water equations of state derived from SUPCRT92 (H2O92D.f), but the messages about this are produced by water.SUPCRT92
rather than subcrt
.
Note that E
and kT
can only be calculated for aqueous species and only if the option (thermo()$opt$water
) for calculations of properties using water
is set to IAPWS
.
On the other hand, if the water
option is ‘SUPCRT’ (the default), E
and kT
can be calculated for water but not for aqueous species.
(This is not an inherent limitation in either formulation, but it is just a matter of implementation.)
Minerals with polymorphic transitions (denoted in OBIGT by having states ‘cr’ (lowest-T phase), ‘cr2’, etc.) can be specified by name with ‘cr’ for the state
or by using a numeric species index for the lowest-T polymorph.
If use.polymorphs
is TRUE, subcrt
uses the transition temperatures calculated from those at P = 1 bar given in OBIGT together with functions of the entropies and volumes of transitions (see dPdTtr
) to determine the stable polymorph at each grid point and uses the properties of that polymorph in the output.
A polymorph
column is added to the output to indicate the stable polymorph at each T-P condition.
If exceed.Ttr
is FALSE
(the default), output values of Gibbs energy are assigned NA beyond the transition temperature of the highest-temperature polymorph.
Set exceed.Ttr
to TRUE
to identify the stable polymorphs by comparing their extrapolated Gibbs energies instead of the tabulated transition temperatures.
This is generally not advised, as extrapolated Gibbs energies may not reliably determine the stable polymorph at extreme temperatures.
Anderson, G. M. and Crerar, D. A. (1993) Thermodynamics in Geochemistry: The Equilibrium Model, Oxford University Press. https://www.worldcat.org/oclc/803272549
Johnson, J. W., Oelkers, E. H. and Helgeson, H. C. (1992) SUPCRT92: A software package for calculating the standard molal thermodynamic properties of minerals, gases, aqueous species, and reactions from 1 to 5000 bar and 0 to 1000°C. Comp. Geosci. 18, 899–947. doi:10.1016/0098-3004(92)90029-Q
Helgeson, H. C., Owens, C. E., Knox, A. M. and Richard, L. (1998) Calculation of the standard molal thermodynamic properties of crystalline, liquid, and gas organic molecules at high temperatures and pressures. Geochim. Cosmochim. Acta 62, 985–1081. doi:10.1016/S0016-7037(97)00219-6
LaRowe, D. E. and Helgeson, H. C. (2007) Quantifying the energetics of metabolic reactions in diverse biogeochemical systems: electron flow and ATP synthesis. Geobiology 5, 153–168. doi:10.1111/j.1472-4669.2007.00099.x
Shock, E. L., Oelkers, E. H., Johnson, J. W., Sverjensky, D. A. and Helgeson, H. C. (1992) Calculation of the thermodynamic properties of aqueous species at high pressures and temperatures: Effective electrostatic radii, dissociation constants and standard partial molal properties to 1000 °C and 5 kbar. J. Chem. Soc. Faraday Trans. 88, 803–826. doi:10.1039/FT9928800803
info
can be used to find species in the thermodynamic database.
makeup
is used by subcrt
for parsing formulas to check mass balance of reactions.
demo("ORP")
and nonideal
for examples using the IS
argument.
## Properties of species subcrt("water") # Change temperature subcrt("water", T = seq(0, 100, 20)) # Change temperature and pressure T <- seq(500, 1000, 100) P <- seq(5000, 10000, 1000) subcrt("water", T = T, P = P) # Temperature-pressure grid subcrt("water", T = c(500, 1000), P = c(5000, 10000), grid = "P") ## Properties of reactions subcrt(c("glucose", "ethanol", "CO2"), c(-1, 2, 2), T = 25) # Use CO2(gas) (or just change "CO2" to "carbon dioxide") subcrt(c("glucose", "ethanol", "CO2"), c(-1, 2, 2), c("aq", "aq", "gas"), T = 25) ## Automatically balance reactions # First define the basis species basis(c("CO2", "H2O", "NH3", "H2S", "O2")) # Auto-balance adds the required amount of H2O and O2 subcrt(c("ethanol", "glucose"), c(-3, 1), T = 37) # An example with H+ basis(c("H2O", "H2S", "O2", "H+")) subcrt(c("HS-", "SO4-2"), c(-1, 1), T = 100) ## Mineral polymorphs # Properties of the stable polymorph at each temperature subcrt("pyrrhotite") # Reactions automatically use stable polymorph subcrt(c("pyrite", "pyrrhotite", "H2O", "H2S", "O2"), c(-1, 1, -1, 1, 0.5)) # Extrapolated properties of the lowest-T polymorph (metastable at higher temperatures) subcrt(c("pyrrhotite"), use.polymorphs = FALSE, exceed.Ttr = TRUE) ## Messages about problems with the calculation # Above the T, P limits for the H2O equations of state subcrt("alanine", T = c(2250, 2251), P = c(30000, 30001), grid = "T") # Psat is not defined above the critical point # (suppressWarnings is used so that checks of examples don't raise warnings) suppressWarnings(subcrt("alanine", T = seq(0, 5000, by = 1000))) ## Minerals with polymorphic transitions # Compare calculated values of heat capacity of iron with # values from Robie and Hemingway, 1995 T.units("K") # We set pressure here otherwise subcrt uses Psat (saturation # vapor pressure of H2O above 100 degrees C) which can't be # calculated above the critical point of H2O (~647 K) s <- subcrt("Fe", T=seq(300, 1800, 20), P=1) plot(s$out[[1]]$T, s$out[[1]]$Cp, type="l", xlab=axis.label("T"), ylab=axis.label("Cp")) # Add points from RH95 RH95 <- read.csv(system.file("extdata/cpetc/RH95.csv", package="CHNOSZ")) points(RH95[,1], RH95[,2]) title(main=paste("Heat capacity of Fe(cr)\n", "(points - Robie and Hemingway, 1995)")) # Reset the units to default values T.units("C") ## Subzero (degrees C) calculations # Uncomment the following to try IAPWS95 instead of SUPCRT92 #water("IAPWS95") # The limit for H2O92D.f (from SUPCRT92) is currently -20 deg C # but we go to -30 knowing properties will become NA sb <- subcrt(c("H2O", "Na+"), T = seq(-30, 10), P = 1)$out # Start plot with extra room on right opar <- par(mar=c(5, 4, 4, 4)) # Plot Delta G plot(sb$water$T, sb$water$G, ylim = c(-264000, -234000), xlab = axis.label("T"), ylab = axis.label("DG0")) points(sb$`Na+`$T, sb$`Na+`$G, pch = 2) # Add Cp # change y-axis par("usr" = c(par("usr")[1:2], -400, 100)) axis(4) mtext(axis.label("Cp0"), side = 4, line = 3) points(sb$water$T, sb$water$Cp, pch = 16) points(sb$`Na+`$T, sb$`Na+`$Cp, pch = 17) legend("topleft", c("H2O Cp", "H2O G", "Na+ Cp", "Na+ G"), pch = c(16, 1, 17, 2)) H2O <- expr.species("H2O") Na <- expr.species("Na+") degC <- expr.units("T") title(main = substitute(H2O~and~Na~to~-20~degC, list(H2O = H2O, Na = Na, degC = degC))) par(opar) ## Calculations using a variable-pressure standard state thermo("opt$varP" = TRUE) # Calculate the boiling point of octane at 2 and 20 bar # We need exceed.Ttr = TRUE because the liquid is metastable # at high temperatures (also, the gas is metastable at low # temperatures, but that doesn't produce NA in the output) sout2 <- subcrt(rep("octane", 2), c("liq", "gas"), c(-1, 1), T = seq(-50, 300, 0.1), P = 2, exceed.Ttr = TRUE)$out sout20 <- subcrt(rep("octane", 2), c("liq", "gas"), c(-1, 1), T = seq(-50, 300, 0.1), P = 20, exceed.Ttr = TRUE)$out # Find T with the Gibbs energy of reaction that is closest to zero Tvap2 <- sout2$T[which.min(abs(sout2$G))] Tvap20 <- sout20$T[which.min(abs(sout20$G))] # Compare these with experimental values (Fig. 1 of Helgeson et al., 1998) Tvap2.exp <- 156 Tvap20.exp <- 276 # Reset varP to FALSE (the default) thermo("opt$varP" = FALSE)
## Properties of species subcrt("water") # Change temperature subcrt("water", T = seq(0, 100, 20)) # Change temperature and pressure T <- seq(500, 1000, 100) P <- seq(5000, 10000, 1000) subcrt("water", T = T, P = P) # Temperature-pressure grid subcrt("water", T = c(500, 1000), P = c(5000, 10000), grid = "P") ## Properties of reactions subcrt(c("glucose", "ethanol", "CO2"), c(-1, 2, 2), T = 25) # Use CO2(gas) (or just change "CO2" to "carbon dioxide") subcrt(c("glucose", "ethanol", "CO2"), c(-1, 2, 2), c("aq", "aq", "gas"), T = 25) ## Automatically balance reactions # First define the basis species basis(c("CO2", "H2O", "NH3", "H2S", "O2")) # Auto-balance adds the required amount of H2O and O2 subcrt(c("ethanol", "glucose"), c(-3, 1), T = 37) # An example with H+ basis(c("H2O", "H2S", "O2", "H+")) subcrt(c("HS-", "SO4-2"), c(-1, 1), T = 100) ## Mineral polymorphs # Properties of the stable polymorph at each temperature subcrt("pyrrhotite") # Reactions automatically use stable polymorph subcrt(c("pyrite", "pyrrhotite", "H2O", "H2S", "O2"), c(-1, 1, -1, 1, 0.5)) # Extrapolated properties of the lowest-T polymorph (metastable at higher temperatures) subcrt(c("pyrrhotite"), use.polymorphs = FALSE, exceed.Ttr = TRUE) ## Messages about problems with the calculation # Above the T, P limits for the H2O equations of state subcrt("alanine", T = c(2250, 2251), P = c(30000, 30001), grid = "T") # Psat is not defined above the critical point # (suppressWarnings is used so that checks of examples don't raise warnings) suppressWarnings(subcrt("alanine", T = seq(0, 5000, by = 1000))) ## Minerals with polymorphic transitions # Compare calculated values of heat capacity of iron with # values from Robie and Hemingway, 1995 T.units("K") # We set pressure here otherwise subcrt uses Psat (saturation # vapor pressure of H2O above 100 degrees C) which can't be # calculated above the critical point of H2O (~647 K) s <- subcrt("Fe", T=seq(300, 1800, 20), P=1) plot(s$out[[1]]$T, s$out[[1]]$Cp, type="l", xlab=axis.label("T"), ylab=axis.label("Cp")) # Add points from RH95 RH95 <- read.csv(system.file("extdata/cpetc/RH95.csv", package="CHNOSZ")) points(RH95[,1], RH95[,2]) title(main=paste("Heat capacity of Fe(cr)\n", "(points - Robie and Hemingway, 1995)")) # Reset the units to default values T.units("C") ## Subzero (degrees C) calculations # Uncomment the following to try IAPWS95 instead of SUPCRT92 #water("IAPWS95") # The limit for H2O92D.f (from SUPCRT92) is currently -20 deg C # but we go to -30 knowing properties will become NA sb <- subcrt(c("H2O", "Na+"), T = seq(-30, 10), P = 1)$out # Start plot with extra room on right opar <- par(mar=c(5, 4, 4, 4)) # Plot Delta G plot(sb$water$T, sb$water$G, ylim = c(-264000, -234000), xlab = axis.label("T"), ylab = axis.label("DG0")) points(sb$`Na+`$T, sb$`Na+`$G, pch = 2) # Add Cp # change y-axis par("usr" = c(par("usr")[1:2], -400, 100)) axis(4) mtext(axis.label("Cp0"), side = 4, line = 3) points(sb$water$T, sb$water$Cp, pch = 16) points(sb$`Na+`$T, sb$`Na+`$Cp, pch = 17) legend("topleft", c("H2O Cp", "H2O G", "Na+ Cp", "Na+ G"), pch = c(16, 1, 17, 2)) H2O <- expr.species("H2O") Na <- expr.species("Na+") degC <- expr.units("T") title(main = substitute(H2O~and~Na~to~-20~degC, list(H2O = H2O, Na = Na, degC = degC))) par(opar) ## Calculations using a variable-pressure standard state thermo("opt$varP" = TRUE) # Calculate the boiling point of octane at 2 and 20 bar # We need exceed.Ttr = TRUE because the liquid is metastable # at high temperatures (also, the gas is metastable at low # temperatures, but that doesn't produce NA in the output) sout2 <- subcrt(rep("octane", 2), c("liq", "gas"), c(-1, 1), T = seq(-50, 300, 0.1), P = 2, exceed.Ttr = TRUE)$out sout20 <- subcrt(rep("octane", 2), c("liq", "gas"), c(-1, 1), T = seq(-50, 300, 0.1), P = 20, exceed.Ttr = TRUE)$out # Find T with the Gibbs energy of reaction that is closest to zero Tvap2 <- sout2$T[which.min(abs(sout2$G))] Tvap20 <- sout20$T[which.min(abs(sout20$G))] # Compare these with experimental values (Fig. 1 of Helgeson et al., 1998) Tvap2.exp <- 156 Tvap20.exp <- 276 # Reset varP to FALSE (the default) thermo("opt$varP" = FALSE)
Swap the basis species defining a chemical system. One basis species is replaced by a new one with a different chemical formula.
swap.basis(species, species2, T = 25) basis.elements(basis = thermo()$basis) element.mu(basis = thermo()$basis, T = 25) basis.logact(emu, basis = thermo()$basis, T = 25) ibasis(species)
swap.basis(species, species2, T = 25) basis.elements(basis = thermo()$basis) element.mu(basis = thermo()$basis, T = 25) basis.logact(emu, basis = thermo()$basis, T = 25) ibasis(species)
basis |
dataframe, a basis definition |
T |
numeric, temperature in Kelvin |
emu |
numeric, chemical potentials of elements |
species |
character, names or formulas of species, or numeric, indices of species |
species2 |
character or numeric, a species to swap in to the basis definition |
swap.basis
allows to change the basis definition by swapping out a basis species for a new one.
Specify the names or formulas of the old and replacement basis species in the first argument.
When the basis definition is changed, any species of interest that were present are deleted, unless the new basis definition has exactly the same elements as before.
In that case, the species are kept; also, the activities of the new basis species are set in order to maintain the chemical potentials of the elements at T
°C and 1 bar.
The other functions are supporting functions: basis.elements
returns the stoichiometric matrix for the current basis definition, element.mu
calculates the chemical potentials of elements corresponding to the activities of the basis species, basis.logact
does the inverse operation, and ibasis
returns the index in the basis set for a given species index (in thermo$OBIGT
), name or formula.
## Swapping basis species # Start with a preset basis definition b1 <- basis("CHNOS+") # Swap H2(aq) for O2(gas) b2 <- swap.basis("O2", "H2") # Put oxygen back in b3 <- swap.basis("H2", "oxygen") # Interconversion of chemical potentials of elements and # logarithms of activities of basis species at high temperature basis("CHNOS+") bl1 <- basis()$logact emu <- element.mu(T = 100) bl2 <- basis.logact(emu, T = 100) # There's no difference round(bl2 - bl1, 10)
## Swapping basis species # Start with a preset basis definition b1 <- basis("CHNOS+") # Swap H2(aq) for O2(gas) b2 <- swap.basis("O2", "H2") # Put oxygen back in b3 <- swap.basis("H2", "oxygen") # Interconversion of chemical potentials of elements and # logarithms of activities of basis species at high temperature basis("CHNOS+") bl1 <- basis()$logact emu <- element.mu(T = 100) bl2 <- basis.logact(emu, T = 100) # There's no difference round(bl2 - bl1, 10)
Read data from NCBI taxonomy files, traverse taxonomic ranks, get scientific names of taxonomic nodes.
getnodes(taxdir) getrank(id, taxdir, nodes=NULL) parent(id, taxdir, rank=NULL, nodes=NULL) allparents(id, taxdir, nodes=NULL) getnames(taxdir) sciname(id, taxdir, names=NULL)
getnodes(taxdir) getrank(id, taxdir, nodes=NULL) parent(id, taxdir, rank=NULL, nodes=NULL) allparents(id, taxdir, nodes=NULL) getnames(taxdir) sciname(id, taxdir, names=NULL)
taxdir |
character, directory where the taxonomy files are kept. |
id |
numeric, taxonomic ID(s) of the nodes of interest. |
nodes |
dataframe, output from |
rank |
character, name of the taxonomic rank of interest. |
names |
dataframe, output from |
These functions provide a convenient way to read data from NCBI taxonomy files (i.e., the contents of taxdump.tar.gz
, which is available from https://ftp.ncbi.nih.gov/pub/taxonomy/).
The taxdir
argument is used to specify the directory where the nodes.dmp
and names.dmp
files are located. getnodes
and getnames
read these files into data frames. getrank
returns the rank (species, genus, etc) of the node with the given taxonomic id
. parent
returns the taxonomic ID of the next-lowest node below that specified by the id
in the argument, unless rank
is supplied, in which case the function descends the tree until a node with that rank is found. allparents
returns all the taxonomic IDs of all nodes between that specified by id
and the root of the tree, inclusive. sciname
returns the scientific name of the node with the given id
.
The id
argument can be of length greater than 1 except for allparents
. If getrank
, parent
, allparents
or sciname
need to be called repeatedly, the operation can be hastened by supplying the output of getnodes
in the nodes
argument and/or the output of getnames
in the names
argument.
## Get information about Homo sapiens from the ## packaged taxonomy files taxdir <- system.file("extdata/taxonomy", package = "CHNOSZ") # H. sapiens' taxonomic id id1 <- 9606 # That is a species getrank(id1, taxdir) # The next step up the taxonomy id2 <- parent(id1, taxdir) print(id2) # That is a genus getrank(id2, taxdir) # That genus is "Homo" sciname(id2, taxdir) # We can ask what phylum is it part of? id3 <- parent(id1, taxdir, "phylum") # Answer: "Chordata" sciname(id3, taxdir) # H. sapiens' complete taxonomy id4 <- allparents(id1, taxdir) sciname(id4, taxdir) ## The names of the organisms in the supplied taxonomy files taxdir <- system.file("extdata/taxonomy", package = "CHNOSZ") id5 <- c(83333, 4932, 9606, 186497, 243232) sciname(id5, taxdir) # These are not all species, though # (those with "no rank" are something like strains, # e.g. Escherichia coli K-12) getrank(id5, taxdir) # Find the species for each of these id6 <- sapply(id5, function(x) parent(x, taxdir = taxdir, rank = "species")) unique(getrank(id6, taxdir)) # "species" # Note that the K-12 is dropped sciname(id6, taxdir) ## The complete nodes.dmp and names.dmp files are quite large, ## so it helps to store them in memory when performing multiple queries ## (this doesn't have a noticeable speed-up for the small files in this example) taxdir <- system.file("extdata/taxonomy", package = "CHNOSZ") nodes <- getnodes(taxdir = taxdir) # All of the node ids in this file id7 <- nodes$id # All of the non-leaf nodes id8 <- unique(parent(id7, nodes = nodes)) names <- getnames(taxdir = taxdir) sciname(id8, names = names)
## Get information about Homo sapiens from the ## packaged taxonomy files taxdir <- system.file("extdata/taxonomy", package = "CHNOSZ") # H. sapiens' taxonomic id id1 <- 9606 # That is a species getrank(id1, taxdir) # The next step up the taxonomy id2 <- parent(id1, taxdir) print(id2) # That is a genus getrank(id2, taxdir) # That genus is "Homo" sciname(id2, taxdir) # We can ask what phylum is it part of? id3 <- parent(id1, taxdir, "phylum") # Answer: "Chordata" sciname(id3, taxdir) # H. sapiens' complete taxonomy id4 <- allparents(id1, taxdir) sciname(id4, taxdir) ## The names of the organisms in the supplied taxonomy files taxdir <- system.file("extdata/taxonomy", package = "CHNOSZ") id5 <- c(83333, 4932, 9606, 186497, 243232) sciname(id5, taxdir) # These are not all species, though # (those with "no rank" are something like strains, # e.g. Escherichia coli K-12) getrank(id5, taxdir) # Find the species for each of these id6 <- sapply(id5, function(x) parent(x, taxdir = taxdir, rank = "species")) unique(getrank(id6, taxdir)) # "species" # Note that the K-12 is dropped sciname(id6, taxdir) ## The complete nodes.dmp and names.dmp files are quite large, ## so it helps to store them in memory when performing multiple queries ## (this doesn't have a noticeable speed-up for the small files in this example) taxdir <- system.file("extdata/taxonomy", package = "CHNOSZ") nodes <- getnodes(taxdir = taxdir) # All of the node ids in this file id7 <- nodes$id # All of the non-leaf nodes id8 <- unique(parent(id7, nodes = nodes)) names <- getnames(taxdir = taxdir) sciname(id8, names = names)
Run reset()
to reset all of the data used in CHNOSZ to default values.
This includes the computational settings, thermodynamic database, and system settings (chemical species).
The system settings are changed using basis
and species
.
To clear the system settings (the default, i.e. no species loaded), run basis("")
; to clear only the formed species, run species(delete = TRUE)
The thermodynamic database is changed using add.OBIGT
and mod.OBIGT
.
To restore the default database without altering the species settings, run OBIGT()
.
The computational settings are changed using water
, P.units
, T.units
, E.units
, and some other commands (e.g. mod.buffer
).
All the data are stored in the thermo
data object in an environment named CHNOSZ
.
thermo()
is a convenience function to access or modify parts of this object, in particular some computational settings, for example, thermo("opt$ideal.H" = FALSE)
(see nonideal
).
The source data are provided with CHNOSZ as *.csv
files in the extdata/thermo
and extdata/OBIGT
directories of the package.
These files are used to build the thermo
object, which is described below.
reset() OBIGT(no.organics = FALSE) thermo(...)
reset() OBIGT(no.organics = FALSE) thermo(...)
no.organics |
logical, load the database without data files for organic species (NOTE: CH4 is listed as an “inorganic” species)? |
... |
list, one or more arguments whose names correspond to the setting to modify |
thermo()$opt
List of computational settings.
Square brackets indicate default values.
Note that the units of G.tol
and Cp.tol
depend on the E_units
for each species in thermo()$OBIGT
.
Therefore, species with E_units
of ‘J’ have a lower absolute tolerance for producing messages (because 4.184 J = 1 cal).
E.units |
character | The user's units of energy ([‘J’] or ‘cal’) (see subcrt ) |
T.units |
character | The user's units of temperature ([‘C’] or ‘K’) |
P.units |
character | The user's units of pressure ([‘bar’] or ‘MPa’) |
state |
character | The default physical state for searching species [‘aq’] (see info ) |
water |
character | Computational option for properties of water ([‘SUPCRT’] or ‘IAPWS’; see water ) |
G.tol |
numeric | Difference in G above which check.GHS produces a message (cal mol-1) [100] |
Cp.tol |
numeric | Difference in Cp above which check.EOS produces a message (cal K-1 mol-1) [1] |
V.tol |
numeric | Difference in V above which check.EOS produces a message (cm3 mol-1) [1] |
varP |
logical | Use variable-pressure standard state for gases? [FALSE ] (see subcrt ) |
IAPWS.sat |
character | State of water for saturation properties [‘liquid’] (see util.water ) |
paramin |
integer | Minimum number of calculations to launch parallel processes [1000] (see palply ) |
ideal.H |
logical | Should nonideal ignore the proton? [TRUE ] |
ideal.e |
logical | Should nonideal ignore the electron? [TRUE ] |
nonideal |
character | Option for charged species in nonideal [Bdot ] |
Setchenow |
character | Option for neutral species in nonideal [bgamma0 ] |
Berman |
character | User data file for mineral parameters in the Berman equations [NA ] |
maxcores |
numeric | Maximum number of cores for parallel calculations with palply [2 ] |
ionize.aa |
numeric | Calculate properties of ionized proteins when H+ is in basis species (see affinity ) [TRUE ]
|
thermo()$element
Dataframe containing the thermodynamic properties of elements taken from Cox et al., 1989, Wagman et al., 1982, and (for Am, Pu, Np, Cm) Thoenen et al., 2014.
The standard molal entropy ((
Z
)) at 25 °C and 1 bar for the “element” of charge (Z
) was calculated from (H2,g) + 2
(
Z
) = 2(H+), where the standard molal entropies of H2,g and H+ were taken from Cox et al., 1989.
The mass of
Z
is taken to be zero.
Accessing this data frame using mass
or entropy
will select the first entry found for a given element; i.e., values from Wagman et al., 1982 will only be retrieved if the properties of the element are not found from Cox et al., 1989.
element |
character | Symbol of element |
state |
character | Stable state of element at 25 °C and 1 bar |
source |
character | Source of data |
mass |
numeric | Mass of element (in natural isotopic distribution; |
referenced to a mass of 12 for 12C) | ||
s |
numeric | Entropy of the compound of the element in its stable |
state at 25 °C and 1 bar (cal K-1 mol-1) | ||
n |
numeric | Number of atoms of the element in its stable |
compound at 25 °C and 1 bar |
thermo()$OBIGT
This dataframe is a thermodynamic database of standard molal thermodynamic properties and equations of state parameters of species. “OrganoBioGeoTherm” is the name of a Windows GUI interface to SUPCRT92 that was produced in Harold C. Helgeson's Laboratory of Theoretical Geochemistry and Biogeochemistry at the University of California, Berkeley. The OBIGT database was originally distributed with that program, and was the starting point for the database in CHNOSZ.
Note the following database conventions:
The combination of name
and state
defines a species in thermo()$OBIGT
. A species cannot be duplicated (this is checked when running reset()
).
English names of inorganic gases are used only for the gas state. The dissolved species is named with the chemical formula. Therefore, info("oxygen")
refers to the gas, and info("O2")
refers to the aqueous species.
Each entry is referenced to one or two literature sources listed in thermo()$refs
.
Use thermo.refs
to look up the citation information for the references.
See the vignette OBIGT for a complete description of the sources of data.
The identifying characteristics of species and their standard molal thermodynamic properties at 25 °C and 1 bar are located in the first 13 columns of thermo()$OBIGT
:
name |
character | Species name |
abbrv |
character | Species abbreviation |
formula |
character | Species formula |
state |
character | Physical state |
ref1 |
character | Primary source |
ref2 |
character | Secondary source |
date |
character | Date of data entry (ISO 8601 extended format) |
model |
character | Model for thermodynamic properties of the species |
E_units |
character | Units of energy: ‘J’ for Joules or ‘cal’ for calories |
G |
numeric | Standard molal Gibbs energy of formation |
from the elements (J|cal mol-1) | ||
H |
numeric | Standard molal enthalpy of formation |
from the elements (J|cal mol-1) | ||
S |
numeric | Standard molal entropy (J|cal mol-1 K-1) |
Cp |
numeric | Standard molal isobaric heat capacity (J|cal mol-1 K-1) |
V |
numeric | Standard molal volume (cm3 mol-1) |
model
must be one of ‘H2O’, ‘HKF’, ‘CGL’, ‘Berman’, ‘AD’, or ‘DEW’.
‘H2O’ is reserved for liquid water, the properties of which are calculated using one of several available models (see water
).
Most aqueous species use ‘HKF’ (the revised Helgeson-Kirkham-Flowers model).
Properties of aqueous species with model
set to ‘AD’ are calculated using the Akinfiev-Diamond model, and those with ‘DEW’ are calculated using the DEW
model.
Many minerals in the default database use the ‘Berman’ model (see Berman
).
All other species use ‘CGL’ (general crystalline, gas, liquid model).
Properties of these species are calculated using a heat capacity function with up to six terms; the exponent on the final term can be defined in the database (see below).
The meanings of the remaining columns depend on the model for each species.
The names of these columns are compounded from those of the parameters in the HKF equations of state and general heat capacity equation; for example, column 13 is named a1.a
.
Scaling of the values by integral powers of ten (i.e., orders of magnitude; OOM) for the HKF parameters (this also includes the DEW model) is based on the usual (but by no means universal) convention in the literature.
Columns 15-22 for aqueous species (parameters in the revised HKF equations of state).
NOTE: Most older papers use units of calories for these parameters, so ‘cal’ is listed here; the actual units for each species are set in the E_units
column.
a1 |
numeric | a1 * 10 (cal mol-1 bar-1) |
a2 |
numeric | a2 * 10-2 (cal mol-1) |
a3 |
numeric | a3 (cal K mol-1 bar-1) |
a4 |
numeric | a4 * 10-4 (cal mol-1 K) |
c1 |
numeric | c1 (cal mol-1 K-1) |
c2 |
numeric | c2 * 10-4 (cal mol-1 K) |
omega |
numeric | ω * 10-5 (cal mol-1) |
Z |
numeric | Charge |
Columns 15-22 for crystalline, gas and liquid species (CP = +
+
-2 +
-0.5 +
2 +
lambda).
NOTE: As of CHNOSZ 2.0.0, OOM scaling for heat capacity coefficients has been removed, and new entries use units of Joules unless indicated by setting
E_units
to ‘cal’.
a |
numeric | (J K-1 mol-1) |
b |
numeric | (J K-2 mol-1) |
c |
numeric | (J K mol-1) |
d |
numeric | (J K-0.5 mol-1) |
e |
numeric | (J K-3 mol-1) |
f |
numeric | (J K-lambda-1 mol-1) |
lambda |
numeric | λ (exponent on the term) |
T |
numeric | Positive value: Temperature (K) of polymorphic transition or phase stability limit |
T |
numeric | Negative value: Opposite of temperature (K) limit of CP equation (see FAQ for details) |
Columns 15-17 for aqueous species using the Akinfiev-Diamond model. Note that the c
column is used to store the parameter. Columns 18-22 are not used.
a |
numeric | (cm3 g-1) |
b |
numeric | (cm3 K0.5 g-1) |
c |
numeric | |
d |
numeric | NA |
e |
numeric | NA |
f |
numeric | NA |
lambda |
numeric | NA |
Z |
numeric | NA |
thermo()$refs
References for thermodynamic data.
key |
character | Source key |
author |
character | Author(s) |
year |
character | Year |
citation |
character | Citation (journal title, volume, and article number or pages; or book or report title) |
note |
character | Short description of the compounds or species in this data source |
URL |
character | URL |
thermo()$buffers
Dataframe which contains definitions of buffers of chemical activity. Each named buffer can be composed of one or more species, which may include any species in the thermodynamic database and/or any protein. The calculations provided by buffer
do not take into account polymorphic transitions of minerals, so individual polymorphs of such minerals must be specified in the buffers.
name |
character | Name of buffer |
species |
character | Name of species |
state |
character | Physical state of species |
logact |
numeric | Logarithm of activity (fugacity for gases) |
thermo()$protein
Data frame of amino acid compositions of selected proteins. Most of the compositions were taken from the SWISS-PROT/UniProt online database (Boeckmann et al., 2003) and the protein and organism names usually follow the conventions adopted there. In some cases different isoforms of proteins are identified using modifications of the protein names; for example, ‘MOD5.M’ and MOD5.N
proteins of ‘YEAST’ denote the mitochondrial and nuclear isoforms of this protein. See pinfo
to search this data frame by protein name, and other functions to work with the amino acid compositions.
protein |
character | Identification of protein |
organism |
character | Identification of organism |
ref |
character | Reference key for source of compositional data |
abbrv |
character | Abbreviation or other ID for protein |
chains |
numeric | Number of polypeptide chains in the protein |
Ala ...Tyr |
numeric | Number of each amino acid in the protein |
thermo()$groups
This is a dataframe with 22 columns for the amino acid sidechain, backbone and protein backbone groups ([Ala]..[Tyr],[AABB],[UPBB]) whose rows correspond to the elements C, H, N, O, S. It is used to quickly calculate the chemical formulas of proteins that are selected using the iprotein
argument in affinity
.
thermo()$basis
Initially NULL
, reserved for a dataframe written by basis
upon definition of the basis species. The number of rows of this dataframe is equal to the number of columns in “...” (one for each element).
... |
numeric | One or more columns of stoichiometric |
coefficients of elements in the basis species | ||
ispecies |
numeric | Rownumber of basis species in thermo()$OBIGT
|
logact |
numeric | Logarithm of activity or fugacity of basis species |
state |
character | Physical state of basis species |
thermo()$species
Initially NULL
, reserved for a dataframe generated by species
to define the species of interest. The number of columns in “...” is equal to the number of basis species (i.e., rows of thermo()$basis
).
... |
numeric | One or more columns of stoichiometric |
coefficients of basis species in the species of interest | ||
ispecies |
numeric | Rownumber of species in thermo()$OBIGT
|
logact |
numeric | Logarithm of activity or fugacity of species |
state |
character | Physical state of species |
name |
character | Name of species |
thermo()$stoich
A precalculated stoichiometric matrix for the default database. This is a matrix, not a data frame, and as such can accept duplicated row names, corresponding to chemical formulas of the species. See retrieve
, and the first test in inst/tinytest/test-retrieve.R
for how to update this.
rownames |
character | Chemical formulas from thermo()$OBIGT
|
... |
numeric | Stoichiometry, one column for each element present in any species |
thermo()$Bdot_acirc
Values of ion size parameter (Å) for species, taken from the UT_SIZES.REF file of the HCh package (Shvarov and Bastrakov, 1999), which is based on Table 2.7 of Garrels and Christ, 1965.
This is used in nonideal
with the default ‘Bdot’ method.
Custom ion size parameters can be added to this vector; to override a default value for a species, either replace the numeric value for that species or prepend a named numeric value (for duplicated species, the first value is used).
See demo("yttrium")
for an example of adding and overriding species.
thermo()$Berman
A data frame with thermodynamic parameters for minerals in the Berman equations, assembled from files in ‘extdata/Berman’ and used in Berman
.
To enable the calculation of thermodynamic properties of polymorphic transitions, higher-temperature polymorphs of minerals are listed in OBIGT with states ‘cr2’, ‘cr3’, etc.
The standard thermodynamic properties of high-temperature polymorphs at 25 °C and 1 bar are apparent values that are consistent with given values of enthalpy of transition (where available) at the transition temperature ().
See the FAQ question “How can minerals with polymorphic transitions be added to the database?” for details of the retrieval of standard thermodynamic properties of polymorphs used in OBIGT.
Cox, J. D., Wagman, D. D. and Medvedev, V. A., eds. (1989) CODATA Key Values for Thermodynamics. Hemisphere Publishing Corporation, New York, 271 p. https://www.worldcat.org/oclc/18559968
Garrels, R. M. and Christ, C. L. (1965) Solutions, Minerals, and Equilibria, Harper & Row, New York, 450 p. https://www.worldcat.org/oclc/517586
Thoenen, T., Hummel, W., Berner, U. and Curti, E. (2014) The PSI/Nagra Chemical Thermodynamic Database 12/07. Paul Scherrer Institut. https://www.psi.ch/en/les/database
Wagman, D. D., Evans, W. H., Parker, V. B., Schumm, R. H., Halow, I., Bailey, S. M., Churney, K. L. and Nuttall, R. L. (1982) The NBS tables of chemical thermodynamic properties. Selected values for inorganic and C1 and C2 organic substances in SI units. J. Phys. Chem. Ref. Data 11 (supp. 2), 1–392. https://srd.nist.gov/JPCRD/jpcrdS2Vol11.pdf
Other data files, including those supporting the examples and vignettes, are documented separately at extdata
.
## Where are the data files in CHNOSZ? system.file("extdata", package = "CHNOSZ") # What files make up OBIGT? # Note: file names with _aq, _cr, _gas, or _liq # are used in the default database dir(system.file("extdata/OBIGT", package = "CHNOSZ")) ## Exploring thermo()$OBIGT # What physical states are present unique(thermo()$OBIGT$state) # Formulas of ten random species n <- nrow(thermo()$OBIGT) thermo()$OBIGT$formula[runif(10)*n] ## Adding an element old <- thermo()$element # Element symbol, state, source (can be anything), # mass, entropy, and number in compound Xprops <- data.frame(element = "X", state = "cr", source = "user", mass = 100, s = 100, n = 1) new <- rbind(old, Xprops) thermo(element = new) # Now "X" is recognized as an element in other functions mass("X10") # Restore default settings to remove X reset()
## Where are the data files in CHNOSZ? system.file("extdata", package = "CHNOSZ") # What files make up OBIGT? # Note: file names with _aq, _cr, _gas, or _liq # are used in the default database dir(system.file("extdata/OBIGT", package = "CHNOSZ")) ## Exploring thermo()$OBIGT # What physical states are present unique(thermo()$OBIGT$state) # Formulas of ten random species n <- nrow(thermo()$OBIGT) thermo()$OBIGT$formula[runif(10)*n] ## Adding an element old <- thermo()$element # Element symbol, state, source (can be anything), # mass, entropy, and number in compound Xprops <- data.frame(element = "X", state = "cr", source = "user", mass = 100, s = 100, n = 1) new <- rbind(old, Xprops) thermo(element = new) # Now "X" is recognized as an element in other functions mass("X10") # Restore default settings to remove X reset()
These functions can be used to turn a list into an array and extract or replace values or take the sum along a certain dimension of an array.
list2array(l) slice(arr, d = NULL, i = 1, value = NULL) dimSums(arr, d = 1, i = NULL) slice.affinity(affinity, d = 1, i = 1)
list2array(l) slice(arr, d = NULL, i = 1, value = NULL) dimSums(arr, d = 1, i = NULL) slice.affinity(affinity, d = 1, i = 1)
l |
a list. |
arr |
an array. |
d |
numeric, what dimension to use. |
i |
numeric, what slice to use. |
value |
values to assign to the portion of an array specified by |
affinity |
list, output from |
list2array
turns a list of array
s, each with the same dimensions, into a new array having one more dimension whose size is equal to the number of initial arrays.
slice
extracts or assigns values from/to the i
th slice(s) in the d
th dimension of an array. Values are assigned to an array if value
is not NULL. This function works by building an expression containing the extraction operator ([
).
slice.affinity
performs a slice operation on the ‘values’ element of the ‘affinity’ variable (which should be the output of affinity
).
dimSums
sums an array along the d
th dimension using only the i
th slices in that dimension. If i
is NULL, all slices in that dimension are summed together. For matrices, dimSums(x,1)
has the same result as colSums(x)
and dimSums(x,2)
has the same result as rowSums(x)
.
# Start with a matrix mat <- matrix(1:12, ncol = 3) # Pay attention to the following when # writing examples that test for identity! identical(1 * mat, mat) # FALSE # Create two matrices that are multiples of the first a <- 1 * mat b <- 2 * mat # These both have two dimensions of lengths 4 and 3 dim(a) # 4 3 # Combine them to make an array with three dimensions x <- list2array(list(a, b)) # The third dimension has length 2 dim(x) # 4 3 2 # The first slice of the third dimension slice(x, 3) # a # The second slice of the third dimension slice(x, 3, 2) # b # 'slice' works just like the bracket operator slice(x, 1) # x[1, , ] slice(x, 1, 2) # x[2, , ] slice(x, 2, 1) # x[, 1, ] slice(x, 2, 1:2) # x[, 1:2, ] # Replace part of the array y <- slice(x, 3, 2, value = a) # Now the second slice of the third dimension == a slice(y, 3, 2) # a # and the sum across the third dimension == b dimSums(y, 3) # b # Taking the sum removes that dimension dim(y) # 4 3 2 dim(dimSums(y, 1)) # 3 2 dim(dimSums(y, 2)) # 4 2 dim(dimSums(y, 3)) # 4 3 # Working with an 'affinity' object basis("CHNOS+") species("alanine") a1 <- affinity(O2 = c(-80, -60)) # i.e. pH = 7 a2 <- affinity(O2 = c(-80, -60), pH = c(0, 14, 7)) # In the 2nd dimension (pH) get the 4th slice (pH = 7) a3 <- slice.affinity(a2, 2, 4) all.equal(a1$values, a3$values) # TRUE
# Start with a matrix mat <- matrix(1:12, ncol = 3) # Pay attention to the following when # writing examples that test for identity! identical(1 * mat, mat) # FALSE # Create two matrices that are multiples of the first a <- 1 * mat b <- 2 * mat # These both have two dimensions of lengths 4 and 3 dim(a) # 4 3 # Combine them to make an array with three dimensions x <- list2array(list(a, b)) # The third dimension has length 2 dim(x) # 4 3 2 # The first slice of the third dimension slice(x, 3) # a # The second slice of the third dimension slice(x, 3, 2) # b # 'slice' works just like the bracket operator slice(x, 1) # x[1, , ] slice(x, 1, 2) # x[2, , ] slice(x, 2, 1) # x[, 1, ] slice(x, 2, 1:2) # x[, 1:2, ] # Replace part of the array y <- slice(x, 3, 2, value = a) # Now the second slice of the third dimension == a slice(y, 3, 2) # a # and the sum across the third dimension == b dimSums(y, 3) # b # Taking the sum removes that dimension dim(y) # 4 3 2 dim(dimSums(y, 1)) # 3 2 dim(dimSums(y, 2)) # 4 2 dim(dimSums(y, 3)) # 4 3 # Working with an 'affinity' object basis("CHNOS+") species("alanine") a1 <- affinity(O2 = c(-80, -60)) # i.e. pH = 7 a2 <- affinity(O2 = c(-80, -60), pH = c(0, 14, 7)) # In the 2nd dimension (pH) get the 4th slice (pH = 7) a3 <- slice.affinity(a2, 2, 4) all.equal(a1$values, a3$values) # TRUE
Show table of references in a web browser or get individual references for species. Check self consistency of individual entries in database.
thermo.refs(key = NULL, keep.duplicates = FALSE) check.EOS(eos, model, prop, return.difference = TRUE) check.GHS(ghs, return.difference = TRUE) check.OBIGT() dumpdata(file) RH2OBIGT(compound = NULL, state = "cr", file = system.file("extdata/adds/RH98_Table15.csv", package = "CHNOSZ"))
thermo.refs(key = NULL, keep.duplicates = FALSE) check.EOS(eos, model, prop, return.difference = TRUE) check.GHS(ghs, return.difference = TRUE) check.OBIGT() dumpdata(file) RH2OBIGT(compound = NULL, state = "cr", file = system.file("extdata/adds/RH98_Table15.csv", package = "CHNOSZ"))
key |
character, numeric, or list; bibliographic reference key(s) |
keep.duplicates |
logical, keep duplicated references? |
eos |
dataframe, equations-of-state parameters in the format of |
model |
character, thermodynamic model (see |
prop |
character, property of interest (‘Cp’ or ‘V’) |
return.difference |
logical, return the difference between database and calculated values? |
ghs |
dataframe, containing G, H and S, in the format of |
file |
character, path to a file |
compound |
character, name of compound(s) in group additivity calculation |
state |
character, physical state of species |
thermo.refs
with default arguments uses browseURL
to display the sources of thermodynamic data in thermo()$refs
, with the URLs in that table showing as hyperlinks in the browser.
Otherwise, if key
is character, the citation information for those reference key
s (including URLs) are returned.
If key
is numeric, the values refer to the species in those rows of thermo()$OBIGT
, and the citation information for each listed reference (thermo()$OBIGT$ref1
, thermo()$OBIGT$ref2
) is returned.
If key
is a list, it is interpreted as the result of a call to subcrt
, and the citation information for each species involved in the calculation is returned.
Only unique references are returned, unless keep.duplicates
is TRUE.
In that case, a single reference for each species is returned, ignoring anything in thermo()$OBIGT$ref2
.
check.EOS
calculates heat capacity (prop = "Cp"
) or volume (prop = "V"
) from equation-of-state parameters at 25 °C and 1 bar.
check.GHS
calculates G (standard molal Gibbs energy of formation from the elements) from H (standard molal enthalpy of formation) and S (standard molal entropy) at 25 °C and 1 bar.
The calculated values of Cp, V, or G are then compared with the given values (i.e., database values).
If return.difference
is TRUE (the default), the difference between the database and calculated values is returned.
If return.difference
is FALSE, the difference is compared with a tolerance setting (see below).
If the absolute value of the difference exceeds the tolerance, the function prints a message and returns the calculated value (not the difference) of the property.
If the absolute value of the difference is less than the tolerance, the function returns NA with no message.
For check.EOS
, the thermodynamic parameters should be provided in eos
, which is a data frame with column names in the same format as thermo$OBIGT
.
For check.GHS
, the data frame should include G, H, S, and the chemical formula of the species.
The default tolerances are 1 J/K.mol or 1 cal/K.mol for Cp (depending on the E_units
for the species), 1 cm3/mol for V, and 100 cal/mol for G.
These can be changed by setting thermo()$opt$Cp.tol
, thermo()$opt$V.tol
, and thermo()$opt$G.tol
.
check.OBIGT
is a function to check self-consistency of each entry in the thermodynamic database, using check.EOS
and check.GHS
.
The output is a table listing only species that exceed at least one of the tolerance limits, giving the species name and state, and DCp, DV and DG, for the calculated differences (only those above the tolerances are given).
Values of DCp and DG are given in the units present in the data files.
This function is used to generate the file found at ‘extdata/adds/OBIGT_check.csv’.
dumpdata
returns all of the available data, from both the default and optional data files, or writes it to a file if file
is not NULL.
The format is the same as thermo$OBIGT
, except for a single prepended column named ‘source’, giving the source of the data (‘OBIGT’ refers to the default database, and ‘DEW’, ‘SLOP98’, and ‘SUPCRT92’ are the optional data files).
RH2OBIGT
implements a group additivity algorithm for standard molal thermodynamic properties and equations of state parameters of crystalline and liquid organic molecules from Richard and Helgeson, 1998. The names of the compound
s and their physical state
are searched for in the indicated file
, that also contains chemical formulas and group stoichiometries; the names of the groups are stored in the column names of this file, and must be present in thermo$OBIGT
. The default file
(extdata/thermo/RH98_Table15.csv
) includes data taken from Table 15 of Richard and Helgeson, 1998 for high molecular weight compounds in ‘cr’ystalline and ‘liq’uid states. An error is produced if any of the compound
-state
combinations is not found in the file
, if any of the group names for a given compound
-state
combination is not found in thermo()$OBIGT
, or if the chemical formula calculated from group additivity (with the aid of i2A
and as.chemical.formula
) is not identical to that listed in the file
.
The values returned (invisible
-y) by mod.OBIGT
are the rownumbers of the affected species.
Richard, L. and Helgeson, H. C. (1998) Calculation of the thermodynamic properties at elevated temperatures and pressures of saturated and aromatic high molecular weight solid and liquid hydrocarbons in kerogen, bitumen, petroleum, and other organic matter of biogeochemical interest. Geochim. Cosmochim. Acta 62, 3591–3636. doi:10.1016/S0016-7037(97)00345-1
# Citation information for Helgeson et al., 1998 thermo.refs("HOK+98") # Two references for alanine thermo.refs(info("alanine")) # Three references for species in the reaction s <- subcrt(c("O2","O2"),c("gas","aq"),c(-1,1)) thermo.refs(s) ## Not run: ## Marked dontrun because it opens a browser # Show the contents of thermo()$refs thermo.refs() ## End(Not run) ## Calculate thermodynamic properties of organic compounds ## using group additivity, after Richard and Helgeson, 1998 RH2OBIGT()
# Citation information for Helgeson et al., 1998 thermo.refs("HOK+98") # Two references for alanine thermo.refs(info("alanine")) # Three references for species in the reaction s <- subcrt(c("O2","O2"),c("gas","aq"),c(-1,1)) thermo.refs(s) ## Not run: ## Marked dontrun because it opens a browser # Show the contents of thermo()$refs thermo.refs() ## End(Not run) ## Calculate thermodynamic properties of organic compounds ## using group additivity, after Richard and Helgeson, 1998 RH2OBIGT()
Generate expressions suitable for axis labels and plot legends describing chemical species, properties and reactions.
expr.species(species, state = "aq", value=NULL, log=FALSE, molality=FALSE, use.state=FALSE, use.makeup=FALSE) expr.property(property, molality = FALSE) expr.units(property, prefix = "", per = "mol") axis.label(label, units = NULL, basis = thermo()$basis, prefix = "", molality = FALSE) describe.basis(ibasis = 1:nrow(basis), basis = thermo()$basis, digits = 1, oneline = FALSE, molality = FALSE, use.pH = TRUE) describe.property(property, value, digits = 0, oneline = FALSE, ret.val = FALSE) describe.reaction(reaction, iname = numeric(), states = NULL) syslab(system = c("K2O", "Al2O3", "SiO2", "H2O"), dash="-") ratlab(top = "K+", bottom = "H+", molality = FALSE)
expr.species(species, state = "aq", value=NULL, log=FALSE, molality=FALSE, use.state=FALSE, use.makeup=FALSE) expr.property(property, molality = FALSE) expr.units(property, prefix = "", per = "mol") axis.label(label, units = NULL, basis = thermo()$basis, prefix = "", molality = FALSE) describe.basis(ibasis = 1:nrow(basis), basis = thermo()$basis, digits = 1, oneline = FALSE, molality = FALSE, use.pH = TRUE) describe.property(property, value, digits = 0, oneline = FALSE, ret.val = FALSE) describe.reaction(reaction, iname = numeric(), states = NULL) syslab(system = c("K2O", "Al2O3", "SiO2", "H2O"), dash="-") ratlab(top = "K+", bottom = "H+", molality = FALSE)
species |
character, formula of a chemical species |
state |
character, designation of physical state |
value |
numeric, logarithm of activity or fugacity of species, or value of other property |
log |
logical, write logarithm of activity/fugacity/molality? |
molality |
logical, use molality (m) instead of activity (a) for aqueous species? |
use.state |
logical, include state in expression? |
use.makeup |
logical, use |
use.pH |
logical, use pH instead of log activity of H+? |
property |
character, description of chemical property |
prefix |
character, prefix for units |
per |
character, denominator in units |
label |
character, description of species, condition or property |
units |
character, description of units |
ibasis |
numeric, which basis species to include |
basis |
data frame, definition of basis species |
digits |
numeric, number of digits to show after decimal point |
oneline |
logical, make descriptions occupy a single line? |
ret.val |
logical, return only the value with the units? |
reaction |
data frame, definition of reaction |
iname |
numeric, show names instead of formulas for these species |
states |
character, if ‘all’, show states for all species; numeric, which species to show states for |
system |
character, thermodynamic components |
dash |
character to use for dash between components |
top |
character, the ion in the numerator of the ratio |
bottom |
character, the ion in the denominator of the ratio |
The expr.*
functions create expression
s using the plotmath
syntax to describe the names and states and logarithms of activity or fugacity of chemical species, conditions including temperature and pressure and chemical properties such as Gibbs energy and volume.
expr.species
constructs a formatted expression using the formula or name of a single chemical species
.
With no other arguments, the formula is just formatted with the appropriate subscripts and superscripts.
Providing the physical state
adds a variable to the expression (a for aqueous species and pure phases, except f for gases).
Set molality
to TRUE to write m instead of a for aqueous species.
The state itself is written in the expression if use.state
is TRUE.
If log
is TRUE, the expression includes a ‘log’ prefix.
Finally, provide a value in value
to write an equation (something like logfO2 = -70), or set it to NA to only write the variable itself (e.g. logfO2).
Set use.makeup
to TRUE to use makeup
to parse the chemical formula.
This was an older default action that had the undesirable effect of reordering and grouping all the elements, and has been replaced with a different splitting algorithm so that coefficients and charges are sub/superscripted without affecting the intervening text.
expr.property
accepts a description in property
that indicates the chemical property of interest.
Uppercase letters are italicized, and lowercase letters are italicized and subscripted.
Other specific characters are parsed as follows (case-sensitive):
‘D’ | Delta |
‘A’ | bold A (chemical affinity) |
‘p’ | subscript italic P (for isobaric heat capacity) |
‘0’ | degree sign (for a standard-state property) |
‘l’ | subscript lambda |
‘'’ | prime symbol |
A ‘0’ gets interpreted as a degree sign only if it does not immediately follow a number (so that e.g. ‘2.303’ can be included in an expression).
Every other character that is one of the letters
or LETTERS
in the description of the property is italicized in the expression; other characters such as numerals or mathematical operators are shown without any special formatting.
Special cases for the property
argument (‘logK’, ‘Eh’, ‘pH’, ‘pe’, ‘IS’ and ‘ZC’) are interpreted as simple expressions, and are not parsed according to the above rules.
expr.units
returns an expression for the units, based on one or more characters appearing in the property
:
‘A’, ‘G’, ‘H’ | energy |
‘Cp’, ‘S’ | energy per Kelvin |
‘V’ | volume |
‘E’ | volume per Kelvin |
‘P’ | pressure |
‘T’ | temperature |
‘Eh’ | electrical potential |
‘IS’ | ionic strength |
If none of those characters appears in the property, the expression is an empty character (no units). If a prefix
is given, it is added to the expression. The denominator of the units (default ‘mol’) is taken from the per
argument; it is applied to all units except for ‘P’, ‘T’, ‘Eh’, and ‘IS’.
axis.label
accepts a generic description of a label
.
If this matches the chemical formula of one of the basis species in the basis
argument, the expression for the label is generated using expr.species
with log
set to the physical state of the basis species.
Otherwise, the expression is built by combining the output of expr.property
with expr.units
(or the value in units
, if it is supplied), placing a comma between the two.
This function is used extensively in diagram
and also appears in many of the examples.
Note that diagram
sets molality
to TRUE if IS
was supplied as an argument to affinity
.
describe.basis
makes an expression summarizing the basis species definition (logarithms of activity or fugacity of the basis species) provided in basis
; only the basis species identified by ibasis
are included.
describe.property
makes an expression summarizing the properties supplied in property
, along with their value
s. The expressions returned by both functions consist of a property, an equals sign, and a value (with units where appropriate); the expressions have a length equal to the number of property/value pairs. If oneline
is TRUE, the property/value pairs are combined into a single line, separated by commas. The number of digits shown after the decimal point in the values is controlled by digits
. If ret.val
is TRUE, only the values and their units are returned; this is useful for labeling plots with values of temperature.
describe.reaction
makes an expression summarizing a chemical reaction.
The reaction
data frame can be generated using subcrt
.
Based on the sign of their reaction coefficients, species are placed on the reactant (left) or product (right) side of the reaction, where the species with their coefficients are separated by plus signs; the two sides of the reaction are separated by a reaction double arrow (Unicode U+21CC).
Coefficients equal to 1 are not shown.
Chemical formulas of species include the physical state if states
is ‘all’, or a numeric value indicating which species to label with the state.
Names of species (as provided in reaction
) are shown instead of chemical formulas for the species identified by iname
.
syslab
formats the given thermodynamic components (using expr.species
) and adds intervening en dashes.
ratlab
produces a expression for the activity ratio between the ions in the top
and bottom
arguments.
The default is a ratio with H+, i.e. (activity of the ion) / [(activity of H+) ^ (charge of the ion)].
util.legend
for other functions to make legends.
demo("saturation")
for examples of syslab
and ratlab
.
## Show descriptions of species and properties on a plot plot(0, 0, xlim = c(1,5), ylim = c(1,5), xlab = "function", ylab = "example") text0 <- function(...) text(..., adj = 0) # Species text0(1, 1, expr.species("CO2")) text0(1, 2, expr.species("CO2", use.state = TRUE)) text0(1, 3, expr.species("CO2", log = TRUE, use.state = TRUE)) text0(1, 4, expr.species("CO2", log = TRUE)) text0(1, 5, expr.species("CO2", log = TRUE, value = -3)) # Properties text0(2, 1, expr.property("A")) text0(2, 2, expr.property("DV")) text0(2, 3, expr.property("DG0f")) text0(2, 4, expr.property("DCp0,r")) text0(2, 5, expr.property("T")) # Units text0(3, 1, expr.units("A", prefix = "k")) text0(3, 2, expr.units("DV")) text0(3, 3, expr.units("DG0f", prefix = "k")) text0(3, 4, expr.units("DCp0,r")) text0(3, 5, expr.units("T")) # axis.label text0(4, 1, axis.label("DG0f")) text0(4, 2, axis.label("T")) text0(4, 3, axis.label("pH")) text0(4, 4, axis.label("Eh")) text0(4, 5, axis.label("IS")) # describe.basis basis("CHNOS+") dbasis <- describe.basis(oneline = TRUE, digits = 0) property <- c("P", "T", "Eh", "pH", "IS") value <- c(1, 42.42, -1, 7, 0.1) dprop <- describe.property(property, value, oneline = TRUE) text(3, 1.5, dbasis) text(3, 2.5, dprop) dbasis <- describe.basis(c(1, 5)) dprop <- describe.property(property[1:2], value[1:2]) legend(2.4, 3.9, legend=c(dbasis, dprop), bty = "n") # describe.reaction # Reaction is automatically balanced because basis species are defined reaction <- subcrt("glucose", -1)$reaction text(3, 4.25, describe.reaction(reaction)) text(3, 4.5, describe.reaction(reaction, states = "all")) text(3, 4.75, describe.reaction(reaction, iname = 1:4)) title(main = "Plot labels for chemical species and thermodynamic properties")
## Show descriptions of species and properties on a plot plot(0, 0, xlim = c(1,5), ylim = c(1,5), xlab = "function", ylab = "example") text0 <- function(...) text(..., adj = 0) # Species text0(1, 1, expr.species("CO2")) text0(1, 2, expr.species("CO2", use.state = TRUE)) text0(1, 3, expr.species("CO2", log = TRUE, use.state = TRUE)) text0(1, 4, expr.species("CO2", log = TRUE)) text0(1, 5, expr.species("CO2", log = TRUE, value = -3)) # Properties text0(2, 1, expr.property("A")) text0(2, 2, expr.property("DV")) text0(2, 3, expr.property("DG0f")) text0(2, 4, expr.property("DCp0,r")) text0(2, 5, expr.property("T")) # Units text0(3, 1, expr.units("A", prefix = "k")) text0(3, 2, expr.units("DV")) text0(3, 3, expr.units("DG0f", prefix = "k")) text0(3, 4, expr.units("DCp0,r")) text0(3, 5, expr.units("T")) # axis.label text0(4, 1, axis.label("DG0f")) text0(4, 2, axis.label("T")) text0(4, 3, axis.label("pH")) text0(4, 4, axis.label("Eh")) text0(4, 5, axis.label("IS")) # describe.basis basis("CHNOS+") dbasis <- describe.basis(oneline = TRUE, digits = 0) property <- c("P", "T", "Eh", "pH", "IS") value <- c(1, 42.42, -1, 7, 0.1) dprop <- describe.property(property, value, oneline = TRUE) text(3, 1.5, dbasis) text(3, 2.5, dprop) dbasis <- describe.basis(c(1, 5)) dprop <- describe.property(property[1:2], value[1:2]) legend(2.4, 3.9, legend=c(dbasis, dprop), bty = "n") # describe.reaction # Reaction is automatically balanced because basis species are defined reaction <- subcrt("glucose", -1)$reaction text(3, 4.25, describe.reaction(reaction)) text(3, 4.5, describe.reaction(reaction, states = "all")) text(3, 4.75, describe.reaction(reaction, iname = 1:4)) title(main = "Plot labels for chemical species and thermodynamic properties")
Calculate the standard molal entropy of elements in a compound; calculate the standard molal Gibbs energy or enthalpy of formation, or standard molal entropy, from the other two; list coefficients of selected elements in a chemical formula; calculate the average oxidation state of carbon. Create a stoichiometric matrix for selected species.
as.chemical.formula(makeup, drop.zero = TRUE) mass(formula) entropy(formula) GHS(formula, G = NA, H = NA, S = NA, T = 298.15, E_units = "J") ZC(formula) i2A(formula)
as.chemical.formula(makeup, drop.zero = TRUE) mass(formula) entropy(formula) GHS(formula, G = NA, H = NA, S = NA, T = 298.15, E_units = "J") ZC(formula) i2A(formula)
makeup |
numeric, object returned by |
drop.zero |
logical, drop elements with a coefficient of zero? |
formula |
character, chemical formulas, or numeric, rownumbers in |
G |
numeric, standard molal Gibbs energy of formation from the elements |
H |
numeric, standard molal enthalpy of formation from the elements |
S |
numeric, standard molal molal entropy |
T |
numeric, temperature in Kelvin |
E_units |
character, energy units (J or cal) |
i2A
returns a stoichiometric matrix representing the elemental composition of the formula
s.
Each column corresponds to an element that is present in at least one of the formulas; some element counts will be zero if not all formula have the same elements.
If a matrix is passed to i2A
it is returned unchanged.
as.chemical.formula
makes a character string representing a chemical formula from a vector of coefficients with names corresponding to the elements (e.g., the output of makeup
) or from a stoichiometric matrix (output of i2A
).
Each elemental symbol is written followed by its coefficient; negative coefficients are signed.
Any coefficients equal to 1 are not explicitly written, and any charge (indicated by makeup
as ‘Z’) is shown as a signed number at the end of the formula.
If the formula is uncharged, and the last element has a negative coefficient, +0 is shown at the end of the formula to indicate a charge of zero.
The remaining functions documented here accept vectors of chemical formulas, species indices, or a mixture of both, or stoichiometric matrices with elements on the columns.
mass
and entropy
return the sums of masses or entropies of elements in each of the formula
s.
The masses are calculated using the masses of the elements in their natural isotopic distribution, and the entropies, in J K mol
, are calculated using the entropies of the compounds of the pure elements in their stable states at 25 °C and 1 bar.
The properties of the elements used by this function are taken from
thermo$element
.
GHS
computes one of the standard molal Gibbs energy or enthalpy of formation from the elements, or standard molal entropy, from values of the other two.
The formula
, G
, H
and S
arguments must all have the same length.
The entropies of the elements (Se
) in each formula
are calculated using entropy
, which gives values in Joules.
If E_units
is ‘cal’, the values are converted to calories.
The equation in effect can be written as , where
and
is the temperature given in
T
(defaults to 298.15 K) (note that G
and H
in the arguments correspond respectively to and
in the equation).
For each formula, if one of
G
, H
, or S
is NA, its value is calculated from the other two.
Otherwise, the values are returned unchanged.
ZC
returns the average oxidation state of carbon () calculated from ratios of the elements in the chemical
formula
s.
The equation used is
, where the
refer to the number of the indicated element in the formula and
is the charge (Dick and Shock, 2011).
The result is
NaN
for any formula that does not contain carbon. Elements other than those shown in the equation are not included in the calculation, and produce a warning.
mass
, entropy
, and ZC
return numeric values.
as.chemical.formula
returns a character object.
GHS
returns a matrix with column names ‘G’, ‘H’ and ‘S’, and i2A
returns a matrix with column names corresponding to the elements in the formulas.
Dick, J. M. and Shock, E. L. (2011) Calculation of the relative chemical stabilities of proteins as a function of temperature and redox chemistry in a hot spring. PLOS One 6, e22782. doi:10.1371/journal.pone.0022782
makeup
, used by mass
and entropy
, and ZC
and i2A
for counting the elements in a formula (the latter two make use of the count.zero
argument).
## Mass and entropy from chemical formulas mass("H2O") entropy("H2O") mass("-1") # electron entropy("-1") ## Different ways to get the formula of alanine iA <- info("alanine") info(iA)$formula as.chemical.formula(makeup(iA)) ## Converting among Gibbs energy, enthalpy, entropy # Calculate the value of G from H and S GHS("H2O", H = water("H")$H, S = water("S")$S) # The result is not exactly equal to the value from water("G"), # probably because of different entropies of the elements ## Average oxidation states of carbon ZC(c("CO2", "CH4", "CHNOSZ")) # 4, -4, 7 si <- info("LYSC_CHICK") # Can use species index or formula ZC(si) ZC(info(si)$formula) ## Calculate the chemical formulas, then ## ZC of all of the proteins in CHNOSZ's database pf <- protein.formula(thermo()$protein) range(mass(pf)) # Use na.rm = TRUE because we have a "protein" with a formula of H2O range(ZC(pf), na.rm = TRUE)
## Mass and entropy from chemical formulas mass("H2O") entropy("H2O") mass("-1") # electron entropy("-1") ## Different ways to get the formula of alanine iA <- info("alanine") info(iA)$formula as.chemical.formula(makeup(iA)) ## Converting among Gibbs energy, enthalpy, entropy # Calculate the value of G from H and S GHS("H2O", H = water("H")$H, S = water("S")$S) # The result is not exactly equal to the value from water("G"), # probably because of different entropies of the elements ## Average oxidation states of carbon ZC(c("CO2", "CH4", "CHNOSZ")) # 4, -4, 7 si <- info("LYSC_CHICK") # Can use species index or formula ZC(si) ZC(info(si)$formula) ## Calculate the chemical formulas, then ## ZC of all of the proteins in CHNOSZ's database pf <- protein.formula(thermo()$protein) range(mass(pf)) # Use na.rm = TRUE because we have a "protein" with a formula of H2O range(ZC(pf), na.rm = TRUE)
Generate expressions describing system conditions that can be added to legends of plots.
lNaCl(x, digits = 2) lS(x, digits = 3) lT(x, digits = 0) lP(x, digits = 0) lTP(x, y, digits = 0) lex(...)
lNaCl(x, digits = 2) lS(x, digits = 3) lT(x, digits = 0) lP(x, digits = 0) lTP(x, y, digits = 0) lex(...)
x |
numeric, value of the property |
digits |
numeric, digits for rounding |
y |
numeric, value of pressure |
... |
language, objects to combine in an expression |
These functions are used to make expressions for common chemical system variables that can be used in plot legends.
lNaCl
describe the molality of NaCl, and lS
the total molality of sulfur.
lT
and lP
describe the temperature and pressure.
lTP
describe the temperature and pressure together, separated by a comma.
The above functions return language objects, which can be combined with lex
to make an expression that when used in legend
appears on multiple lines.
plot.new() l <- lex(lTP(100, "Psat"), lNaCl(1), lS(1e-3)) legend("center", l)
plot.new() l <- lex(lTP(100, "Psat"), lNaCl(1), lS(1e-3)) legend("center", l)
Identify list elements that have the maximum (or minimum) values.
which.pmax(x, maximum = TRUE)
which.pmax(x, maximum = TRUE)
x |
list of numeric vectors |
maximum |
logical, find maximum values or minimum values? |
which.pmax
takes a list of equal-length numeric vectors or equal-dimension arrays in x
and returns the index of the list element that has the maximum value at each point.
Change maximum
to FALSE
to find the minimum values instead.
Calculate and temperature of polymorphic transitions; scale logarithms of activity to a desired total activity.
dPdTtr(ispecies, ispecies2 = NULL) Ttr(ispecies, ispecies2 = NULL, P = 1, dPdT = NULL) GHS_Tr(ispecies, Htr) unitize(logact = NULL, length = NULL, logact.tot = 0)
dPdTtr(ispecies, ispecies2 = NULL) Ttr(ispecies, ispecies2 = NULL, P = 1, dPdT = NULL) GHS_Tr(ispecies, Htr) unitize(logact = NULL, length = NULL, logact.tot = 0)
ispecies |
numeric, species index of a mineral phase |
ispecies2 |
numeric, species index of next mineral phase (the default is ispecies + 1) |
P |
numeric, pressure (bar) |
dPdT |
numeric, values of ( |
Htr |
numeric, enthalpy(ies) of transition (cal/mol) |
logact |
numeric, logarithms of activity |
length |
numeric, numbers of residues |
logact.tot |
numeric, logarithm of total activity |
dPdTtr
returns values of , where
represents the transition temperature, of the polymorphic transition at the high-
stability limit of the
ispecies
in thermo()$OBIGT
(other than checking that the names match, the function does not check that the species in fact represent different phases of the same mineral).
dPdTtr
takes account of the Clapeyron equation, =
, where
and
represent the changes in entropy and volume of polymorphic transition, and are calculated using
subcrt
at Ttr from the standard molal entropies and volumes of the two phases involved.
Using values of dPdT
calculated using dPdTtr
or supplied in the arguments, Ttr
returns as a function of P
values of the upper transition temperature of the mineral phase represented by ispecies
.
GHS_Tr
can be used to calculate values of G, H, and S at Tr for the cr2, cr3, and cr4 phases in the database.
It combines the given Htr
(enthalpies of transition) with the database values of GHS @ Tr only for the phase that is stable at 298.15 K (cr) and the transition temperatures and Cp coefficients for higher-temperature phases, to calculate the GHS @ Tr (i.e. low-temperature metastable conditions) of the phases that are stable at higher temperatures.
unitize
scales the logarithms of activities given in logact
so that the logarithm of total activity of residues is equal to zero (i.e. total activity of residues is one), or to some other value set in logact.tot
.
length
indicates the number of residues in each species.
If logact
is NULL, the function takes the logarithms of activities from the current species definition.
If any of those species are proteins, the function gets their lengths using protein.length
.
# We need the Helgeson et al., 1978 minerals for this example add.OBIGT("SUPCRT92") # That replaces the existing enstatite with the first phase; # the other phases are appended to the end of thermo()$OBIGT i1 <- info("enstatite") i2 <- info("enstatite", "cr2") i3 <- info("enstatite", "cr3") # (dP/dT) of transitions dPdTtr(i1, i2) # first transition dPdTtr(i2, i3) # second transition # Temperature of transitions (Ttr) as a function of P Ttr(i1, i2, P = c(1,10,100,1000)) Ttr(i2, i3, P = c(1,10,100,1000)) # Restore default database OBIGT() # Calculate the GHS at Tr for the high-temperature phases of iron # using transition enthalpies from the SUPCRT92 database (sprons92.dat) Htr <- c(326.0, 215.0, 165.0) iiron <- info("iron") GHS_Tr(iiron, Htr) # The results calculated above are stored in the database ... info(1:3 + iiron)[, c("G", "H", "S")] # ... meaning that we can recalculate the transition enthalpies using subcrt() sapply(info(0:2 + iiron)$T, function(T) { # A very small T increment around the transition temperature T <- convert(c(T-0.01, T), "C") # Use suppressMessages to make the output less crowded sres <- suppressMessages(subcrt("iron", T = T, P = 1)) diff(sres$out$iron$H) }) ## Scale logarithms of activity # Suppose we have two proteins whose lengths are 100 and # 200; what are the logarithms of activity of the proteins # that are equal to each other and that give a total # activity of residues equal to unity? logact <- c(-3, -3) # could be any two equal numbers length <- c(100, 200) logact.tot <- 0 loga <- unitize(logact, length, logact.tot) # The proteins have equal activity loga[1] == loga[2] # The sum of activity of the residues is unity all.equal(sum(10^loga * length), 1) ## What if the activity of protein 2 is ten times that of protein 1? logact <- c(-3, -2) loga <- unitize(logact, length, logact.tot) # The proteins have unequal activity, # but the activities of residues still add up to one all.equal(loga[2] - loga[1], 1) all.equal(sum(10^loga * length), 1)
# We need the Helgeson et al., 1978 minerals for this example add.OBIGT("SUPCRT92") # That replaces the existing enstatite with the first phase; # the other phases are appended to the end of thermo()$OBIGT i1 <- info("enstatite") i2 <- info("enstatite", "cr2") i3 <- info("enstatite", "cr3") # (dP/dT) of transitions dPdTtr(i1, i2) # first transition dPdTtr(i2, i3) # second transition # Temperature of transitions (Ttr) as a function of P Ttr(i1, i2, P = c(1,10,100,1000)) Ttr(i2, i3, P = c(1,10,100,1000)) # Restore default database OBIGT() # Calculate the GHS at Tr for the high-temperature phases of iron # using transition enthalpies from the SUPCRT92 database (sprons92.dat) Htr <- c(326.0, 215.0, 165.0) iiron <- info("iron") GHS_Tr(iiron, Htr) # The results calculated above are stored in the database ... info(1:3 + iiron)[, c("G", "H", "S")] # ... meaning that we can recalculate the transition enthalpies using subcrt() sapply(info(0:2 + iiron)$T, function(T) { # A very small T increment around the transition temperature T <- convert(c(T-0.01, T), "C") # Use suppressMessages to make the output less crowded sres <- suppressMessages(subcrt("iron", T = T, P = 1)) diff(sres$out$iron$H) }) ## Scale logarithms of activity # Suppose we have two proteins whose lengths are 100 and # 200; what are the logarithms of activity of the proteins # that are equal to each other and that give a total # activity of residues equal to unity? logact <- c(-3, -3) # could be any two equal numbers length <- c(100, 200) logact.tot <- 0 loga <- unitize(logact, length, logact.tot) # The proteins have equal activity loga[1] == loga[2] # The sum of activity of the residues is unity all.equal(sum(10^loga * length), 1) ## What if the activity of protein 2 is ten times that of protein 1? logact <- c(-3, -2) loga <- unitize(logact, length, logact.tot) # The proteins have unequal activity, # but the activities of residues still add up to one all.equal(loga[2] - loga[1], 1) all.equal(sum(10^loga * length), 1)
Initialize a new plot window using preset parameters, add an axis or title to a plot, generate labels for axes and subplots, add stability lines for water, get colors for a set of numeric values.
thermo.plot.new(xlim, ylim, xlab, ylab, cex = par("cex"), mar = NULL, lwd = par("lwd"), side = c(1,2,3,4), mgp = c(1.7, 0.3, 0), cex.axis = par("cex"), col = par("col"), yline = NULL, axs = "i", plot.box = TRUE, las = 1, xline = NULL, grid = "", col.grid = "gray", ...) thermo.axis(lab = NULL, side = 1:4, line = 1.5, cex = par("cex"), lwd = par("lwd"), col = par("col"), grid = "", col.grid = "gray", plot.line = FALSE) label.plot(x, xfrac = 0.07, yfrac = 0.93, paren = FALSE, italic = FALSE, ...) usrfig() label.figure(x, xfrac = 0.05, yfrac = 0.95, paren = FALSE, italic = FALSE, ...) water.lines(eout, which = c("oxidation","reduction"), lty = 2, lwd = 1, col = par("fg"), plot.it = TRUE) mtitle(main, line = 0, spacing = 1, ...) ZC.col(z)
thermo.plot.new(xlim, ylim, xlab, ylab, cex = par("cex"), mar = NULL, lwd = par("lwd"), side = c(1,2,3,4), mgp = c(1.7, 0.3, 0), cex.axis = par("cex"), col = par("col"), yline = NULL, axs = "i", plot.box = TRUE, las = 1, xline = NULL, grid = "", col.grid = "gray", ...) thermo.axis(lab = NULL, side = 1:4, line = 1.5, cex = par("cex"), lwd = par("lwd"), col = par("col"), grid = "", col.grid = "gray", plot.line = FALSE) label.plot(x, xfrac = 0.07, yfrac = 0.93, paren = FALSE, italic = FALSE, ...) usrfig() label.figure(x, xfrac = 0.05, yfrac = 0.95, paren = FALSE, italic = FALSE, ...) water.lines(eout, which = c("oxidation","reduction"), lty = 2, lwd = 1, col = par("fg"), plot.it = TRUE) mtitle(main, line = 0, spacing = 1, ...) ZC.col(z)
xlim |
numeric, limits of the |
ylim |
numeric, limits of the |
xlab |
character, |
ylab |
character, |
cex |
numeric, character expansion factor for labels |
mar |
numeric, width (number of lines) of margins on each side of plot |
lwd |
numeric, line width |
side |
numeric, which sides of plot to draw axes |
mgp |
numeric, sizes of margins of plot |
cex.axis |
numeric, character expansion factor for names of axes |
col |
character, color |
yline |
numeric, margin line on which to plot |
axs |
character, setting for axis limit calculation |
plot.box |
logical, draw a box around the plot? |
las |
numeric, style for axis labels |
xline |
numeric, margin line on which to plot |
grid |
character, type of grid (‘major’, ‘minor’, or ‘both’) |
col.grid |
character, color of the grid lines |
plot.line |
logical, draw axis lines? |
... |
further arguments passed to |
lab |
character, axis label |
line |
numeric, margin line on which to place axis label or plot title |
x |
character, label to place on plot |
xfrac |
numeric, fractional location on |
yfrac |
numeric, fractional location on |
paren |
logical, add parentheses around label text? |
italic |
logical, italicize label text? |
eout |
data frame, output of |
which |
character, which of oxidation/reduction lines to plot |
lty |
numeric, line type |
plot.it |
logical, plot the lines? |
main |
character, text for plot title |
spacing |
numeric, spacing between multiple lines |
z |
numeric, set of values |
thermo.plot.new
sets parameters for a new plot, creates a new plot using plot.new
, and adds the axes tick marks to the plot.
Plot parameters (see par
) including cex
, mar
, lwd
, mgp
and axs
can be given, as well as a numeric vector in side
identifying which sides of the plot receive tick marks.
yline
, if present, denotes the margin line (default par('mgp')[1]
) where the y-axis name is plotted.
thermo.axis
is the function that actually adds the axes, including inward-pointing major and minor tick marks (often used for thermodynamic property diagrams).
Use grid
to add a grid to the plot, corresponding to either the major ticks (solid lines), minor ticks (dashed lines), or both.
The grid can be made by adding grid
argument to diagram
, or by calling thermo.axis
after diagram
(see example).
water.lines
plots lines representing the oxidation and reduction stability limits of water on Eh/pe/logfO2/logfH2 vs pH/T/P diagrams.
The x- and y-variables and their ranges are taken from eout
.
Values of T, P, pH, and logaH2O, not corresponding to either axis, are also taken from eout
.
which
controls which lines are drawn (‘oxidation’, ‘reduction’, or both (the default)).
The value of swapped
in the output reflects whether pH, T, or P is on the x-axis (TRUE) or y-axis (FALSE).
NA
is returned for any diagram for variables that can not be processed (including diagrams with more than 2 variables).
label.plot
and label.figure
add identifying text within the plot region and figure region.
The value given for x
is made into a label, optionally italicized and with parentheses (like (a)).
The location of the label is controlled by xfrac
and yfrac
(the fractional coordinates of either the plot or figure region), and ...
can include other parameters such as cex
and adj
that are passed to text
.
usrfig
returns the limits of the figure region in “user” coordinates (i.e. the limits of the plot region, from par("usr")
).
It is a supporting function for label.figure
but is also useful for other circumstances where information must be added at a particular location in a figure.
mtitle
can be used to add a multi-line title to a plot.
It loops over each element of main
and places it on a separate margin line using mtext
.
The spacing of the last (bottom) line from the edge of the plot is specified by line
.
This function exists to facilitate using expression
s in multiline titles.
ZC.col
uses colorspace) to generate colors from a diverging palette (red - light grey - blue) corresponding to the values in z
.
Red is associated with lower values of z
.
This function is intended to generate colors for distinguishing average oxidation state of carbon ZC
, but any numeric values can be supplied.
diagram
uses thermo.plot.new
to set up a new plot, unless the argument tplot
is set to FALSE in diagram
.
basis(c("H2S", "H2O", "H+", "e-")) species(c("HS-", "H2S", "HSO4-", "SO4-2")) a <- affinity(pH = c(0, 12), Eh = c(-1, 1), T = 200) opar <- par(mfrow = c(2, 2)) diagram(a, grid = "both") title(main = 'diagram(a, grid = "both")') diagram(a, grid = "major") title(main = 'diagram(a, grid = "major")') diagram(a, grid = "minor") title(main = 'diagram(a, grid = "minor")') diagram(a, fill = "terrain") thermo.axis(grid = "major", col.grid = "slategray") title(main = 'thermo.axis(grid = "major")') par(thermo()$opar) par(opar)
basis(c("H2S", "H2O", "H+", "e-")) species(c("HS-", "H2S", "HSO4-", "SO4-2")) a <- affinity(pH = c(0, 12), Eh = c(-1, 1), T = 200) opar <- par(mfrow = c(2, 2)) diagram(a, grid = "both") title(main = 'diagram(a, grid = "both")') diagram(a, grid = "major") title(main = 'diagram(a, grid = "major")') diagram(a, grid = "minor") title(main = 'diagram(a, grid = "minor")') diagram(a, fill = "terrain") thermo.axis(grid = "major", col.grid = "slategray") title(main = 'thermo.axis(grid = "major")') par(thermo()$opar) par(opar)
Return chemical formulas of groups in proteins, and calculate heat capacity using an additivity model from the literature.
MP90.cp(protein, T) group.formulas()
MP90.cp(protein, T) group.formulas()
protein |
proteins specified in any format usable by |
T |
numeric, temperature in °C |
group.formulas
returns the chemical formulas of each of the 20 common amino acid residues in proteins, as well as the terminal -H and -H (treated as the [H2O] group).
MP90.cp
takes protein
(name of protein) and T
(one or more temperatures in °C and returns the additive heat capacity (J mol ) of the unfolded protein using values of heat capacities of the residues taken from Makhatadze and Privalov, 1990.
Those authors provided values of heat capacity at six points between 5 and 125 °C; this function interpolates (using
splinefun
) values at other temperatures.
Makhatadze, G. I. and Privalov, P. L. (1990) Heat capacity of proteins. 1. Partial molar heat capacity of individual amino acid residues in aqueous solution: Hydration effect J. Mol. Biol. 213, 375–384. doi:10.1016/S0022-2836(05)80197-4
ionize.aa
for an example that compares MP90.cp
with heat capacities calculated in CHNOSZ at different temperatures and pHs.
Return names or one- or three-letter abbreviations of amino acids.
aminoacids(nchar = 1, which = NULL)
aminoacids(nchar = 1, which = NULL)
nchar |
numeric, |
which |
character, which amino acids to name |
aminoacids
returns the one-letter abbreviations (nchar
=‘1’) or the three-letter abbreviations (nchar
=‘3’) or the names of the neutral amino acids (nchar
=‘""’) or the names of the amino acids with ionized side chains (nchar
=‘"Z"’).
The output includes 20 amino acids in alphabetic order by 1-letter abbreviation (the order used in thermo()$protein
), unless which
is provided, indicating the desired amino acids (either as 1- or 3-letter abbreviations or names of the neutral amino acids).
protein.formula
for calculating the chemical formulas of proteins.
# Three-letter abbreviations of amino acids aminoacids(3)
# Three-letter abbreviations of amino acids aminoacids(3)
These functions convert values between units and set the user's preferred units.
P.units(units = NULL) T.units(units = NULL) E.units(units = NULL) convert(value, units, T = 298.15, P = 1, pH = 7, logaH2O = 0)
P.units(units = NULL) T.units(units = NULL) E.units(units = NULL) convert(value, units, T = 298.15, P = 1, pH = 7, logaH2O = 0)
units |
character, name of units to set or convert to/from |
value |
numeric, value(s) to be converted |
T |
numeric, temperature (Kelvin), used in ‘G’-‘logK’, ‘pe’-‘Eh’ and ‘logfO2’-‘E0’ conversions |
P |
numeric, pressure (bar), used in ‘logfO2’-‘E0’ conversions |
pH |
numeric, pH, used in ‘logfO2’-‘E0’ conversions |
logaH2O |
numeric, logarithm of activity of water, used in ‘logfO2’-‘E0’ conversions |
The units settings are used by subcrt
, affinity
, and diagram
to accept input in or convert output to the units desired by the user.
The settings, which can be queried or changed with T.units
, E.units
and P.units
, refer to the units of temperature (C
or K
), energy (J
or cal
), and pressure (bar
or MPa
).
(The first value in each of those pairs refers to the default units).
The actual units conversions are handled by convert
, through which values
are transformed into destination units
(names not case sensitive).
The possible conversions and settings for the units
argument are shown in the following table.
Note that ‘Eh’ and ‘E0’ both stand for the value of Eh (oxidation-reduction potential in volts); they have different names so that one can choose to convert between Eh and either ‘pe’ or ‘logfO2’.
property | units | setting of units argument |
temperature | °C, K | C , K |
pressure | bar, MPa | bar , MPa |
energy | cal, J | cal , J |
energy | J, cm bar |
joules , cm3bar |
energy | J, [none] | G , logK |
oxidation potential | volt, [none] | Eh , pe |
oxidation potential | volt, [none] | E0 , logfO2 |
Another use of the function is to convert the results from solubility
into parts per billion, million, or thousand.
These destination units are specified by ‘ppb’, ‘ppm’, or ‘ppt’.
Additionally, the logarithms can be chosen with ‘logppb’, ‘logppm’, and ‘logppt’.
See demo("contour")
and demo("sphalerite")
for examples.
## Direct usage of convert # Temperature (Kelvin) to degrees C convert(273.15, "C") # Temperature (degrees C) to Kelvin convert(100, "K") # Gibbs energy (J mol-1) to/from logK convert(1000, "logK") convert(1000, "logK", T = 373.15) convert(1, "G") # Eh (volt) to pe convert(-1, "pe") convert(-1, "pe", T = 373.15) # logfO2 to E0 (volt) convert(-80, "E0") convert(-80, "E0", pH = 5) convert(-80, "E0", pH = 5, logaH2O = -5) # Convert from calories to Joules convert(1, "J") # 1 cal = 4.184 J # Convert from Joules to calories convert(1, "cal") # 1 J = 0.239 cal # Convert cm3bar to Joules convert(10, "joules") # 10 cm3.bar = 1 J ## Setting the units # Make K the units for temperature arguments to subcrt() and affinity() T.units("K") # Return to default - degrees C T.units("C")
## Direct usage of convert # Temperature (Kelvin) to degrees C convert(273.15, "C") # Temperature (degrees C) to Kelvin convert(100, "K") # Gibbs energy (J mol-1) to/from logK convert(1000, "logK") convert(1000, "logK", T = 373.15) convert(1, "G") # Eh (volt) to pe convert(-1, "pe") convert(-1, "pe", T = 373.15) # logfO2 to E0 (volt) convert(-80, "E0") convert(-80, "E0", pH = 5) convert(-80, "E0", pH = 5, logaH2O = -5) # Convert from calories to Joules convert(1, "J") # 1 cal = 4.184 J # Convert from Joules to calories convert(1, "cal") # 1 J = 0.239 cal # Convert cm3bar to Joules convert(10, "joules") # 10 cm3.bar = 1 J ## Setting the units # Make K the units for temperature arguments to subcrt() and affinity() T.units("K") # Return to default - degrees C T.units("C")
Utility functions for properties of water and steam.
WP02.auxiliary(property, T = 298.15) rho.IAPWS95(T = 298.15, P = 1, state="", trace=0) water.AW90(T = 298.15, rho = 1000, P = 0.1)
WP02.auxiliary(property, T = 298.15) rho.IAPWS95(T = 298.15, P = 1, state="", trace=0) water.AW90(T = 298.15, rho = 1000, P = 0.1)
property |
character, property to calculate |
T |
numeric, temperature (K) |
P |
numeric, pressure (units of bar, except MPa for |
state |
character, state or phase of H2O |
trace |
integer number |
rho |
numeric, density (kg m |
Auxiliary equations to the IAPWS-95 formulation (Wagner and Pruß, 2002) are provided in WP02.auxiliary
.
The property
for this function can be one of ‘P.sigma’ (saturation vapor pressure in MPa), ‘dP.sigma.dT’ (derivative of saturation vapor pressure with respect to temperature), or ‘rho.liquid’ or ‘rho.vapor’ (density of liquid or vapor in kg m).
rho.IAPWS95
implements a root-finding technique (using uniroot
) to determine the values of density for the stable phase of H2O at the given temperature and pressure.
The state
option is used internally in order to determine the stable phase at conditions close to saturation (0.9999*PSAT <= P <= 1.00005*PSAT, where PSAT is the saturation pressure calculated by WP02.auxiliary
).
Alternatively, the user can specify a state
of ‘liquid’ or ‘vapor’ to force the calculation of density for the corresponding phase, even if it is metastable (e.g. superheated water, supercooled steam; this option has no effect in the supercritical region).
The state
is set in calls by water.IAPWS95
to the value in thermo()$opt$IAPWS.sat
(default ‘liquid’) so that higher-level functions (water
, subcrt
) take properties for that state along the saturation curve.
Diagnostic messages are printed if trace
is positive (it is also included in the call to uniroot
).
water.AW90
provides values of the static dielectric constant (epsilon
) calculated using equations given by Archer and Wang, 1990.
Archer, D. G. and Wang, P. M. (1990) The dielectric constant of water and Debye-Hückel limiting law slopes. J. Phys. Chem. Ref. Data 19, 371–411. https://srd.nist.gov/JPCRD/jpcrd383.pdf
Wagner, W. and Pruß, A. (2002) The IAPWS formulation 1995 for the thermodynamic properties of ordinary water substance for general and scientific use. J. Phys. Chem. Ref. Data 31, 387–535. doi:10.1063/1.1461829
# Calculate density of stable phase at 500 K, 500 bar rho <- rho.IAPWS95(T = 500, P = 500) # Calculate pressure (= 50 MPa) at this density IAPWS95("P", T = 500, rho = rho) # Calculate dielectric constant water.AW90(T = 500, rho = rho, P = 50) # Density along saturation curve T <- seq(273.15, 623.15, 25) WP02.auxiliary(T = T) # liquid from WP02 WP02.auxiliary("rho.vapor", T) # vapor from WP02 # WP02.auxiliary gives a close estimate of saturation pressure... T <- 445:455 P.sigma <- WP02.auxiliary("P.sigma", T) # ... but alternates between being just on the liquid or vapor side # (low rho: steam; high rho: water) rho.IAPWS95(T, convert(P.sigma, "bar")) # thermo()$opt$IAPWS.sat allows for choosing liquid or vapor or "" thermo("opt$IAPWS.sat" = "") # Shows artifactual vapor-liquid transition water.IAPWS95("V", T, "Psat") # The calculated Psat, while not exact, should be close enough for most # geochemical calculations to select liquid or vapor oldwat <- water("IAPWS95") thermo("opt$IAPWS.sat" = "vapor") V.vapor <- subcrt("water", T=convert(445:455, "C"))$out[[1]]$V thermo("opt$IAPWS.sat" = "liquid") # the default V.liquid <- subcrt("water", T=convert(445:455, "C"))$out[[1]]$V all(V.vapor > V.liquid) # TRUE water(oldwat)
# Calculate density of stable phase at 500 K, 500 bar rho <- rho.IAPWS95(T = 500, P = 500) # Calculate pressure (= 50 MPa) at this density IAPWS95("P", T = 500, rho = rho) # Calculate dielectric constant water.AW90(T = 500, rho = rho, P = 50) # Density along saturation curve T <- seq(273.15, 623.15, 25) WP02.auxiliary(T = T) # liquid from WP02 WP02.auxiliary("rho.vapor", T) # vapor from WP02 # WP02.auxiliary gives a close estimate of saturation pressure... T <- 445:455 P.sigma <- WP02.auxiliary("P.sigma", T) # ... but alternates between being just on the liquid or vapor side # (low rho: steam; high rho: water) rho.IAPWS95(T, convert(P.sigma, "bar")) # thermo()$opt$IAPWS.sat allows for choosing liquid or vapor or "" thermo("opt$IAPWS.sat" = "") # Shows artifactual vapor-liquid transition water.IAPWS95("V", T, "Psat") # The calculated Psat, while not exact, should be close enough for most # geochemical calculations to select liquid or vapor oldwat <- water("IAPWS95") thermo("opt$IAPWS.sat" = "vapor") V.vapor <- subcrt("water", T=convert(445:455, "C"))$out[[1]]$V thermo("opt$IAPWS.sat" = "liquid") # the default V.liquid <- subcrt("water", T=convert(445:455, "C"))$out[[1]]$V all(V.vapor > V.liquid) # TRUE water(oldwat)
Calculate thermodynamic and electrostatic properties of water.
water(property = NULL, T = 298.15, P = "Psat", P1 = TRUE) water.SUPCRT92(property=NULL, T = 298.15, P = 1, P1 = TRUE) water.IAPWS95(property=NULL, T = 298.15, P = 1) water.DEW(property=NULL, T = 373.15, P = 1000)
water(property = NULL, T = 298.15, P = "Psat", P1 = TRUE) water.SUPCRT92(property=NULL, T = 298.15, P = 1, P1 = TRUE) water.IAPWS95(property=NULL, T = 298.15, P = 1) water.DEW(property=NULL, T = 373.15, P = 1000)
property |
character, computational setting or property(s) to calculate |
T |
numeric, temperature (K) |
P |
numeric, pressure (bar), or ‘Psat’ for vapor-liquid saturation |
P1 |
logical, output pressure of 1 bar below 100 °C instead of calculated values of ‘Psat’? |
These functions compute the thermodynamic (Gibbs energy and it derivatives) and electrostatic (dielectric constant and its derivatives) properties of liquid or supercritical H2O as a function of temperature and pressure using equations of state taken from the literature.
The high-level function water
performs different computations, depending on the setting of thermo()$opt$water
:
Thermodynamic and electrostatic properties are calculated using a FORTRAN subroutine taken from the SUPCRT92 software package (Johnson et al., 1992). See more information below.
Thermodynamic properties are calculated using an implementation in R code of the IAPWS-95 formulation (Wagner and Pruss, 2002), and electrostatic properties are calculated using the equations of Archer and Wang, 1990. See IAPWS95
and more information below.
Thermodynamic and electrostatic properties are calculated using the Deep Earth Water (DEW) model (Sverjensky et al., 2014). The defaults for T
and P
reflect the minimum values for applicability of the model; calculations at lower T
and/or P
points fall back to using ‘SUPCRT92’. See DEW
.
Calling the function with no arguments returns the current computational setting.
Use e.g. water("DEW")
to make the setting; the previous setting (at the time of the function call) is returned invisibly.
Subsequent calculations with water
, or other functions such as subcrt
and affinity
, will use that setting.
The allowed property
s for water
are one or more of those given below, depending on the computational setting; availability is shown by an asterisk.
Note that some of the properties that can actually be calculated using the different formulations are not implemented here.
Except for rho
, the units are those used by Johnson and Norton, 1991.
Property | Description | Units | IAPWS95 | SUPCRT92 | DEW |
A |
Helmholtz energy | J mol |
* | * | NA |
G |
Gibbs energy | J mol |
* | * | * |
S |
Entropy | J K mol |
* | * | NA |
U |
Internal energy | J mol |
* | * | NA |
H |
Enthalpy | J mol |
* | * | NA |
Cv |
Isochoric heat capacity | J K mol |
* | * | NA |
Cp |
Isobaric heat capacity | J K mol |
* | * | NA |
Speed |
Speed of sound | cm s |
NA | * | NA |
alpha |
Coefficient of isobaric expansivity | K |
NA | * | NA |
beta |
Coefficient of isothermal compressibility | bar |
NA | * | NA |
epsilon |
Dielectric constant | dimensionless | NA | * | * |
visc |
Dynamic viscosity | g cm s |
NA | * | NA |
tcond |
Thermal conductivity | J cm s K |
NA | * | NA |
tdiff |
Thermal diffusivity | cm s |
NA | * | NA |
Prndtl |
Prandtl number | dimensionless | NA | * | NA |
visck |
Kinematic viscosity | cm s |
NA | * | NA |
albe |
Isochoric expansivity | bar K |
NA | * | NA |
-compressibility | |||||
ZBorn |
Z Born function | dimensionless | NA | * | NA |
YBorn |
Y Born function | K |
* | * | NA |
QBorn |
Q Born function | bar |
* | * | * |
daldT |
Isobaric temperature derivative | K |
NA | * | NA |
of expansibility | |||||
XBorn |
X Born function | K |
* | * | NA |
NBorn |
N Born function | bar |
* | NA | NA |
UBorn |
U Born function | bar K |
* | NA | NA |
V |
Volume | cm mol |
* | * | * |
rho |
Density | kg m |
* | * | * |
Psat |
Saturation vapor pressure | bar | * | * | NA |
E |
Isobaric expansivity | cm K |
NA | * | NA |
kT |
Isothermal compressibility | cm bar |
NA | * | NA |
de.dT |
Temperature derivative | K |
* | NA | NA |
of dielectric constant | |||||
de.dP |
Pressure derivative | bar |
* | NA | NA |
of dielectric constant | |||||
P |
Pressure | bar | * | NA | NA |
A_DH |
A Debye-Huckel parameter | kg mol |
* | * | * |
B_DH |
B Debye-Huckel parameter | kg mol cm |
* | * | * |
Call water.SUPCRT92
, water.IAPWS95
, or water.DEW
with no arguments to list the available properties.
water.SUPCRT92
interfaces to the FORTRAN subroutine taken from the SUPCRT92 package (H2O92D.F) for calculating properties of water.
These calculations are based on data and equations of Levelt-Sengers et al., 1983, Haar et al., 1984, and Johnson and Norton, 1991, among others (see Johnson et al., 1992).
A value of P
set to ‘Psat’ refers to one bar below 100 °C, otherwise to the vapor-liquid saturation pressure at temperatures below the critical point (‘Psat’ is not available at temperatures above the critical point).
water.SUPCRT92
provides a limited interface to the FORTRAN subroutine; some functions provided there are not made available here (e.g., using variable density instead of pressure, or calculating the properties of steam).
The stated temperature limits of validity of calculations in water.SUPCRT92
are from the greater of 0 °C or the melting temperature at pressure, to 2250 °C (Johnson et al., 1992).
Valid pressures are from the greater of zero bar or the melting pressure at temperature to 30000 bar.
The present functions do not check these limits and will attempt calculations for any range of input parameters, but may return NA
for properties that fail to be calculated at given temperatures and pressures and/or produce warnings or even errors when problems are encountered.
Starting with version 0.9-9.4, a check for minimum pressure (in valTP function in H2O92D.f) has been bypassed so that properties of H2O can be calculated using water.SUPCRT92
at temperatures below the 0.01 °C triple point.
A primary check is still enforced (Tbtm), giving a minimum valid temperature of 253.15 K.
water.IAPWS95
is a wrapper around IAPWS95
, rho.IAPWS95
and water.AW90
.
water.IAPWS95
provides for calculations at specific temperature and pressure; density, needed for IAPWS95
, is inverted from pressure using rho.IAPWS95
.
The function also contains routines for calculating the Born functions as numerical derivatives of the static dielectric constant (from water.AW90
).
For compatibility with geochemical modeling conventions, the values of Gibbs energy, enthalpy and entropy output by IAPWS95
are converted by water.IAPWS95
to the triple point reference state adopted in SUPCRT92
(Johnson and Norton, 1991; Helgeson and Kirkham, 1974).
water.IAPWS95
also accepts setting P
to ‘Psat’, with the saturation pressure calculated from WP02.auxiliary
; by default the returned properties are for the liquid, but this can be changed to the vapor in thermo()$opt$IAPWS.sat
.
A_DH
and B_DH
are solvent parameters in the “B-dot” (extended Debye-Huckel) equation (Helgeson, 1969; Manning, 2013).
A data frame, the number of rows of which corresponds to the number of input temperature-pressure pairs.
Archer, D. G. and Wang, P. M. (1990) The dielectric constant of water and Debye-Hückel limiting law slopes. J. Phys. Chem. Ref. Data 19, 371–411. doi:10.1063/1.555853
Haar, L., Gallagher, J. S. and Kell, G. S. (1984) NBS/NRC Steam Tables. Hemisphere, Washington, D. C., 320 p. https://www.worldcat.org/oclc/301304139
Helgeson, H. C. and Kirkham, D. H. (1974) Theoretical prediction of the thermodynamic behavior of aqueous electrolytes at high pressures and temperatures. I. Summary of the thermodynamic/electrostatic properties of the solvent. Am. J. Sci. 274, 1089–1098. doi:10.2475/ajs.274.10.1089
Helgeson, H. C. (1969) Thermodynamics of hydrothermal systems at elevated temperatures and pressures. Am. J. Sci. 267, 729–804. doi:10.2475/ajs.267.7.729
Johnson, J. W. and Norton, D. (1991) Critical phenomena in hydrothermal systems: state, thermodynamic, electrostatic, and transport properties of HO in the critical region. Am. J. Sci. 291, 541–648. doi:10.2475/ajs.291.6.541
Johnson, J. W., Oelkers, E. H. and Helgeson, H. C. (1992) SUPCRT92: A software package for calculating the standard molal thermodynamic properties of minerals, gases, aqueous species, and reactions from 1 to 5000 bar and 0 to 1000°C. Comp. Geosci. 18, 899–947. doi:10.1016/0098-3004(92)90029-Q
Levelt-Sengers, J. M. H., Kamgarparsi, B., Balfour, F. W. and Sengers, J. V. (1983) Thermodynamic properties of steam in the critical region. J. Phys. Chem. Ref. Data 12, 1–28. doi:10.1063/1.555676
Manning, C. E. (2013) Thermodynamic modeling of fluid-rock interaction at mid-crustal to upper-mantle conditions. Rev. Mineral. Geochem. 76, 135–164. doi:10.2138/rmg.2013.76.5
Sverjensky, D. A., Harrison, B. and Azzolini, D. (2014) Water in the deep Earth: The dielectric constant and the solubilities of quartz and corundum to 60 kb and 1,200 °C. Geochim. Cosmochim. Acta 129, 125–145. doi:10.1016/j.gca.2013.12.019
Wagner, W. and Pruss, A. (2002) The IAPWS formulation 1995 for the thermodynamic properties of ordinary water substance for general and scientific use. J. Phys. Chem. Ref. Data 31, 387–535. doi:10.1063/1.1461829
## Calculations along saturation curve T <- seq(273.15, 623.15, 25) # Liquid density, from SUPCRT92 water("rho", T = T, P = "Psat") # Values of the saturation pressure, Gibbs energy water(c("Psat", "G"), T = T, P = "Psat") # Derivatives of the dielectric constant (Born functions) water(c("QBorn", "YBorn", "XBorn"), T = T, P = "Psat") # Now at constant pressure water(c("QBorn", "YBorn", "XBorn"), T = T, P = 2000) ## Comparing the formulations T <- convert(c(25, 100, 200, 300), "K") # IAPWS-95 oldwat <- water("IAPWS95") water(water.IAPWS95(), T = T) # Deep Earth Water (DEW) water("DEW") water(water.DEW(), T = T, P = 1000) # SUPCRT92 (the default) water(oldwat) water(water.SUPCRT92(), T = T) ## Calculating Q Born function # After Table 22 of Johnson and Norton, 1991 T <- rep(c(375, 400, 425, 450, 475), each = 5) P <- rep(c(250, 300, 350, 400, 450), 5) w <- water("QBorn", T = convert(T, "K"), P = P) # The rest is to make a neat table w <- as.data.frame(matrix(w[[1]], nrow = 5)) colnames(w) <- T[1:5*5] rownames(w) <- P[1:5] print(w)
## Calculations along saturation curve T <- seq(273.15, 623.15, 25) # Liquid density, from SUPCRT92 water("rho", T = T, P = "Psat") # Values of the saturation pressure, Gibbs energy water(c("Psat", "G"), T = T, P = "Psat") # Derivatives of the dielectric constant (Born functions) water(c("QBorn", "YBorn", "XBorn"), T = T, P = "Psat") # Now at constant pressure water(c("QBorn", "YBorn", "XBorn"), T = T, P = 2000) ## Comparing the formulations T <- convert(c(25, 100, 200, 300), "K") # IAPWS-95 oldwat <- water("IAPWS95") water(water.IAPWS95(), T = T) # Deep Earth Water (DEW) water("DEW") water(water.DEW(), T = T, P = 1000) # SUPCRT92 (the default) water(oldwat) water(water.SUPCRT92(), T = T) ## Calculating Q Born function # After Table 22 of Johnson and Norton, 1991 T <- rep(c(375, 400, 425, 450, 475), each = 5) P <- rep(c(250, 300, 350, 400, 450), 5) w <- water("QBorn", T = convert(T, "K"), P = P) # The rest is to make a neat table w <- as.data.frame(matrix(w[[1]], nrow = 5)) colnames(w) <- T[1:5*5] rownames(w) <- P[1:5] print(w)