Äîêóìåíò âçÿò èç êýøà ïîèñêîâîé ìàøèíû. Àäðåñ îðèãèíàëüíîãî äîêóìåíòà : http://www.geol.msu.ru/deps/geochems/soft/en/logK.doc Äàòà èçìåíåíèÿ: Tue Feb 11 19:24:55 2014 Äàòà èíäåêñèðîâàíèÿ: Thu Feb 27 23:32:05 2014 Êîäèðîâêà:

Yu. Shvarov and E. Bastrakov


Compatible with Unitherm version 4.5


logK package: UT2K and R2K utilities


Summary

UT2K and R2K Windows utilities are intended for batch calculation of log K
values of specified chemical reactions using a Unitherm database. In
addition, UT2K generates a file with a set of reactions for a specified
chemical system using the species kept by Unitherm.

The range of permissible temperatures and pressures is limited by the MHKF
model for the aqueous species (up to 1000 ºC and 5000 bar).

The utilities are consistent and have some overlap in functionality; they
can produce almost identical output files with tabulated log K values.
However, they are organised slightly differently due to the difference in
the source data they use.

Installation

Utilities UT2K and R2K are installed simultaneously in the same folder by
the provided Setup program. After the installation, we recommend you to
create shortcuts for these utilities in an easily accessible location. This
will allow you to change working folders for these programs using the box
"Start in" or "Working folder" of the shortcut properties.

You can remove the utilities only simultaneously, using the "Add/Remove
Programs" item of the Windows Control Panel.


Introduction to UT2K

UT2K is an interactive program. It allows you to create the definition of
your system in terms of chemical reactions from scratch. To this end, you
need to choose the required Unitherm species from the offered lists and to
specify temperatures and pressures for log K tabulation.

The output data are kept in the following optional files that can be
switched on and off during the program session:

logK.txt (similar to the R2K logK.txt file; see below)
React.txt (the full list of the generated reactions that can be optionally
used by R2K)

Additional output files - System.txt, System.st, and TPset.txt - are
generated whenever you choose logK.txt and React.txt as output files,
respectively.

System.txt contains the definition of your system in terms of chemical
elements, master species, and dependent species. Optionally, this
information can be complemented by ion sizes for aqueous species, molar
volumes for minerals, and molecular weights for all species.

System.st is a binary system file for equilibrium modelling using the HCh
software package. This file defines your chemical system in terms of
chemical elements, possible phases, and phase species (components).

TPset.txt defines the TP grid that can be used by R2K.


Introduction to R2K

R2K utility is non-interactive. To run, it requires three input text files:

R2K.ini (optionally, UT2K.ini)
React.txt
TPset.txt

R2K.ini is an initialisation file that specifies the path to a Unitherm
database. If missing, this file can be substituted by the UT2K.ini file in
the same working folder.

React.txt contains stoichiometry of chemical reactions of your interest.
The easiest way to obtain this file is to copy it from a Unitherm database
(UT_react.ref) if you earlier saved your reactions there. Alternatively,
you can create this file manually using a simple text editor (e.g.,
Notepad) and following the Unitherm conventions for the UT_react.ref files.

TPset.txt defines the required T-P table. Formats of T and P definitions
are the same as in Unitherm (see file UT_table.ref in your database).

Note: If required, files TPset.txt and React.txt can be generated by
UT2K.

The calculated log K values are saved in the logK.txt file.

The detailed description of the utilities is provided below.


Utilities limitations


|Temperature range |0-1000 ºC |
|Pressure range |0-5000 bar |
|The lowest possible water density (lower |0.32 g/cm¨ |
|densities are marked as "gas") | |
|Max. number of temperatures in all log K |21 |
|tables | |
|Max. number of pressures in 2D tables of the |7 |
|"grid" type | |
|Number of pressures in 1D tables of the "path"|Equal to the number of |
|type |temperatures |
|Number of reactions in output files from UT2K |Limited by the number of |
|(logK.txt and React.txt) |species in the Unitherm |
| |database |
|Number of reactions in a single React.txt file|Not limited |
|for R2K | |
|Number of reactants in a single reaction |10 |
|Number of elements in a single reactant |15 |
|Max. stoichiometric coefficient in a reaction |99.9999 |


UT2K

Utility UT2K is intended to support log K-based programs for calculation of
chemical equlibria. Using the Unitherm database, UT2K creates a list of the
"master species" of the aqueous solution, generates chemical reactions of
formation of the dependent aqueous species, minerals, and gases, and
calculates log K values of these reactions.


Starting UT2K

You can start UT2K from the Start menu or from Windows Explorer as any
other program. In this case, the working folder will be the folder
containing the utility. As all the results are written in the working
folder into files with the fixed names, we do not recommend this mode of
working.

For the different problems at hand (i.e., for different chemical systems),
we recommend to work in the different folders. Thus, the best way to start
UT2K (and R2K) is to use the shortcut that specifies the required startup
folder.


Working with UT2K

You work with the utility in a dialog mode. In a general case, you do not
need to complete any preparatory work before the first working session. The
only file UT2K is looking for after the start is the initialisation file
UT2K.ini.

If UT2K.ini is not found, the utility starts working "from scratch". In
this case, the first action of the program is to ask the user about the
location of the Unitherm database. This information is mandatory -
cancellation of this action results in quitting the program. Normally,
UT2K.ini will contain the path to a database, so this start of the working
session is not typical.

If UT2K.ini is found, the utility reads its information and sets all the
working modes specified in this file.

A typical start:

At the beginning of a UT2K session you are presented with the main starting
dialog that allows you to choose the following options:

(a) To start your work from the selection of the required chemical
elements. This option will limit the list of species that will be
presented to you at the next working step.

(b) To start your work from the selection of the master species.

(c) To jump straight to the final program dialog that allows you to start
calculations (this button is disabled if you do not have a data set ready
for calculations).

(d) To change the path to the database (the current path to a database is
specified in the dialog's title).

(e) To quit the program without calculations.


UT2K is designed as Windows Wizard: to define and solve your problem, you
are guided through a number of dialogs, at each step making a number of
specified choices. After that, the program outputs the required results and
finishes its work. The dialogs are numbered (Step 1, Step 2, etc), with the
current number specified in the dialog's title. On completing a dialog, you
have an option of proceeding to the next one, or returning to the previous
one with or without keeping the changes that you have made in the current
dialog. Also, you can jump straight to the final dialog if this option is
permitted by the current status of your problem.

The dialogs are as follows:

|Dialo|Task |Dialog content |
|g | | |
|Step |Selection of |The full list of the available chemical |
|1 |chemical elements |elements as defined by the content of the |
| |forming species of |chosen Unitherm database. |
| |your chemical | |
| |system | |
|Step |Selection of the |The list of the available aqueous species |
|2 |master (basis) |limited by the set of the chosen chemical |
| |species of aqueous |elements and by the content of the Unitherm |
| |solution |database. |
| | |Note: The option (b) of the main dialog ("Skip |
| | |to choosing master species") allows you to |
| | |start your work straight from this step, with |
| | |an automatic selection of all the chemical |
| | |elements available from Unitherm. |
| | |Note: This step is critical. There is a number |
| | |of constraints imposed on the chosen set of the|
| | |master species: |
| | |1. The number of the master species must be one|
| | |or more. |
| | |2. All the master species should be independent|
| | |(i.e., none of these species can be formed by |
| | |other master species). |
| | |Also, it is advisable to observe the following |
| | |condition: |
| | |The set of the master species should contain |
| | |all the chemical elements chosen at Step 1. |
| | |This condition is verified by the program, and |
| | |you will get a warning message if it is not |
| | |observed. |
| | |If the set of the master species does not allow|
| | |to define the formation reactions of all the |
| | |dependent species (i.e., the set of the master |
| | |species is not sufficient to build redox |
| | |reactions), this set will be automatically |
| | |augmented by the electron (e-). |
| | |On the completion of Step 2 (when you confirm |
| | |your selection), UT2K verifies the |
| | |correspondence between the set of the elements |
| | |and set of the master species. The results of |
| | |Step 1 can be corrected here (i.e., the set of |
| | |the elements can be reduced if you do not have |
| | |the sufficient number of the master species). |
| | |The set of the chemical elements verified at |
| | |this stage is kept in all the subsequent steps;|
| | |it can be modified only by returning to Step 1.|
|Step |Selection of the |The list of the available aqueous species |
|3 |dependent aqueous |formed by the chemical elements verified at |
| |species |Step 2 (including the master species). |
| | |If the definition of your chemical system is |
| | |prepared for the first time (i.e., without the |
| | |initialisation file), then all the non-master |
| | |species are automatically pre-selected. |
| | |In all the other cases, the program will |
| | |preserve the set of the previously chosen |
| | |aqueous species whenever possible. |
|Steps|Selection of the |The lists of the available minerals and gases |
|4 & 5|minerals and gases |formed by the chemical elements verified at |
| |respectively |Step 2. |
| | |The program will not pre-select any species by |
| | |default; however, it will recall the previous |
| | |selections from the UT2K.ini file if available.|
|Last |Setting calculation|You can set the following options: |
|step |options for the |1. Parameters of the T-P table for log K |
| |prepared data set |tabulation (the set of temperatures and |
| | |pressures). The syntax of strings defining the |
| | |temperature-pressure sets corresponds to the |
| | |conventions adopted in Unitherm. |
| | |Two types of tables are allowed: |
| | |"Grid " - two-dimensional tables of T & P (up |
| | |to 21 temperatures and 7 pressures) |
| | |"Path " - one-dimensional table (array) of |
| | |log K values where each value corresponds to |
| | |one pair of T-P values. In this case, the |
| | |number of specified temperatures must be equal |
| | |to the number of specified pressures; the |
| | |maximum number of pairs (calculation points) is|
| | |21. |
| | |2. Additional data that can be included in the |
| | |output file logK.txt (see below): |
| | |Tables of parameters of the Debye-HÝckel |
| | |equation for the specified T-P conditions (A, |
| | |B, b-dot). |
| | |Ion size parameters for calculation of activity|
| | |coefficients of aqueous species (Å), molar |
| | |volumes of minerals, molecular weights of all |
| | |species. |
| | |Tabulated log K values for the half-reaction |
| | |2H2O = O2,g + 4H+ + 4e-. These values can be |
| | |used to calculate Eh values of a chemical |
| | |system. |
| | |3. The set of the output files: |
| | |File logK.txt contains the main output from |
| | |UT2K: tabulated log K values for the reaction |
| | |of formation of the specified species from the |
| | |master species (plus, optionally, for the Eh |
| | |reaction); and, optionally, tabulated values of|
| | |parameters of the Debye-HÝckel equation. |
| | |Simultaneously with the logK.txt file, UT2K |
| | |creates file System.txt. This file contains the|
| | |lists of the chemical elements of your system, |
| | |master species, the dependent species, and |
| | |their stoichiometric matrixes. Optionally, |
| | |System.txt can contain ion size parameters for |
| | |aqueous species (Å), molar volumes of minerals |
| | |(cm¨/mol), and molecular weights of all |
| | |species. |
| | |File React.txt contains the list of the |
| | |generated reactions in the conventional |
| | |Unitherm format. This file can be processed by |
| | |the R2K utility. |
| | |For the same purpose, simultaneously with the |
| | |React.txt file, UT2K creates file TPset.txt |
| | |(see the documentation for R2K for details). |
| | |File UT2K.ini contains all the information |
| | |about the current system (including the path to|
| | |the database and the working modes). If you |
| | |mark the UT2K.ini checkbox, in your next |
| | |session UT2K will recall the same system. If |
| | |you leave it blank, UT2K.ini will not be saved;|
| | |your next session will start with the same |
| | |status as you current one. If you want to save |
| | |the current settings with the blank status of |
| | |this checkbox (i.e., if you want to make this |
| | |status permanent upon starting UT2K), make this|
| | |checkbox shaded by a repetitive mouse click. |
| | |Compared to others, this object has 3 states |
| | |that can be cyclically switched upon every |
| | |mouse click. |
| | |Clicking the Finish button on this dialog |
| | |results in the completion of all the specified |
| | |calculations and quitting the program. |


Tips on using the UT2K interface

Not all the operations of controlling graphical objects of the UT2K dialogs
exactly follow the Windows standards. In this section, we draw your
attention to these differences.

1. When selecting items from the offered lists, the multiselect mode is
switched on from the very beginning. Every new mouse click on a list item
acts as if you press the CTRL key on the keyboard. A mouse click on the
previously selected item results in its deselecting, and the other way
round.

2. You can select a group of subsequent items using the SHIFT key as
usual (note that the multiselect mode will be preserved in this case as
well).

3. The keyboard provides many more options for working with the lists
than the mouse:



|To |Use |
|Select or Deselect items |SPACE or INSERT |
|Move within the list |ARROWS, PAGE UP, PAGE DOWN, HOME, END |
|Select the whole list |CTRL+A |
|Change the selection status of all| |
|the list items starting from the | |
|current position of the cursor bar| |
|to the end of the list: | |
|Select all |+ |
|Deselect all |- (minus) |
|Invert the selection |* |


Note: The list accepts the keyboard commands only when it has the
focus. At the first instance of the dialog display, the focus is kept
by the button Next. To set the focus on a UT2K list using the keyboard,
press the TAB key or the UP arrow key. The subsequent pressing the TAB
key will return focus to the Next button.

4. While working in any list, three keyboard keys are always connected
with the dialog buttons:

Pressing ENTER is equivalent to clicking the Next button.

The second permanently active key is BACKSPACE. It is always connected
with the button Back.

The third key - ESC - does not have an analogue compared to working with
mouse. This key, similar to BACKSPACE, results in moving one step back.
However, in distinction from BACKSPACE, the changes made in the current
dialog window are not kept.


UT2K output files

Most of the output data are kept in text files, with a special HCh-
compatible data kept in a binary file (System.st).

Text files

The content of the UT2K output text files is quite self-explanatory. Only a
few details require a special explanation:

1. Files TPset.txt and System.txt are intended as input files for other
programs. Thus, there is a provision for adding non-processed comment
lines designated at the beginning by the hash symbol (#).

2. In the file System.txt, the column immediately following the last
column of the stoichiometric coefficients table, contains the charge
values for aqueous species.

For all other types of species, the same column may contain the special
symbol *R*. This symbol identifies species containing non-integer
stoichiometric coefficients. See logK.txt file for the complete chemical
formula.

3. Optionally, the file System.txt contains two additional columns:

3.1. Ion size parameters for aqueous species (å) and molar volumes of
minerals (cm¨/mol).

3.2. Molecular weights of all species.



Binary System.st file

The UT2K program can be used to prepare a binary system file for
equilibrium modelling using the HCh software package. This file defines
your chemical system in terms of chemical elements, possible phases, and
phase species (components). Please see HCh documentation for more details.

The HCh system file is created whenever you select the logK.txt check box
from the Output files group of the final step of the UT2K wizard. The file
has a fixed name System.st.

Due to limitations of the UT2K program, System.st can contain only the
following possible phases:

|Minerals |Optional| |
|(Individual phases)| | |
|Gaseous mixture |Optional| |
|Aqueous solution |Mandator|UT2K master species + dependent |
| |y |aqueous species |

Optional lists of minerals and the gas phase are included when you select
at least one species from the appropriate UT2K lists.

Note: By default, the mixing model for the gaseous mixture is defined
as "real" (Peng-Robinson Stryjek-Vera equation of state). If necessary,
you can re-define it as "ideal" using the editing tools of the Main
program of HCh.

Though the System.st file will be equivalent to the System.txt file in
terms of the specified chemical system, there are some differences. These
differences stem from the specifications of the Gibbs minimisation code of
HCh:

1. There is a different order of phases in two files:

|System.s|minerals - gas phase - aqueous solution |
|t | |
|System.t|master species - dependent aqueous species - minerals|
|xt |- gases |

2. The aqueous solution combines the master and dependent aqueous species
and re-arranges them according to the order of the aqueous species in the
chosen Unitherm database.
3. The duplicates of the aqueous species that are allowed in UT2K are
automatically removed from System.st.

Note: In a routine UT2K working session, the master species will be
excluded from the pre-selected list of the aqueous species. However, in
a general case, the dependent aqueous species can replicate the master
species. Thus, the total number of the aqueous species in the System.st
file may be less than the number of the aqueous species in the
System.txt file.

In addition, there are some constraints imposed by current Gibbs
limitations:

1. The number of the chemical elements in your system must not exceed 30.
2. The number of minerals ("individual phases") must not exceed 255.
3. The number of possible species in any solution phase must not exceed
255.

If you breach any of these rules, the file System.st will not be created.
Any previous version of the System.st file will be deleted from your
working folder to avoid inconsistency with the newly created System.txt
file. You will get a warning message "File System.st not created: Too many
elements / aqueous species / minerals / gases". These conditions are
verified by the program in the specified order (elements - aqueous species
- minerals - gases).


R2K

R2K utility is a Windows utility intended for calculation of log K of
reactions. R2K has no graphical interface; it uses text files both for
input and output. All the thermodynamic properties of species are taken
from a Unitherm database.


Input data

The utility uses a complete set of Unitherm data files. Thus, an instance
of a Unitherm database must be available for the program. Three additional
text files for a R2K working folder should be provided by the user:

R2K.ini - an initialisation file that specifies the path to a Unitherm
database (if missing, this file can be substituted by the UT2K.ini file;
see "Running R2K" below)
TPset.txt - a file that describes output tables of log K values
React.txt - a file with list of chemical reactions of interest


Format of the R2K.ini file

This text file contains one mandatory line and one optional line:

The mandatory line contains the path to the required Unitherm database. Its
format is:

UTpath= (e.g., UTpath=C:\HCh\Unitherm\)

The optional line switches on the output of the parameters of the Debye-
HÝckel equation (A, B, and b-dot) into the result file logK.txt. Its format
is

D-H=n

where n accepts two values: 0 (zero, do not generate the Debye-HÝckel
tables - default), and 1 (generate the Debye-HÝckel tables).

Format of the TPset.txt file

TPset.txt consists of several lines. None of these lines is mandatory:

. Any line beginning with the hash symbol (#) is a comment line ignored
by the program.
. A line beginning with the keyword "type=" defines the type of log K
tables generated by the program. You can use two types of tables:

1) The line "type=grid" defines two-dimensional output T-P tables similar
to the tables generated by Unitherm.
2) Alternatively, the line "type=path" defines one-dimensional tables
(arrays) of log K values (similar to arrays of log K values in data
files of the GWB package).

The default type is "grid".

. A line beginning with the keyword "t=" defines the sequence of
temperatures (ºC). If omitted, R2K uses the standard Unitherm set of
temperatures.
. A line beginning with the keyword "p=" defines the sequence of
pressures (bar). If omitted, R2K uses the standard Unitherm set of
pressures. Like in Unitherm, the zero value (0) in the list of pressures
represents the saturated vapour pressure.

All the lines in this file can follow in any order. If there are two or
more lines of the same type, R2K will use the last one.


Format of the file React.txt

This file has the same structure as the file UT_react.ref from Unitherm.
Thus, the most simple way to create it is to copy (or rename) an original
UT_react.ref file keeping chemical reactions. The only difference is that
React.txt has no limitation on the number of the included reactions.

If you wish to create or modify this file manually, you need to follow the
template of the original. However, you can simplify your job keeping in
mind the following:

. The first line of React.txt (the title) must always begin with the
word "Component" (the rest of the symbols are optional).
. The lines that separate the reactions can be shortened: they must
only begin with the minus (-) sign; the same is the true for the second
(separation) line that follows the title.
. Reactant names can begin from any column, but their length is limited
by 14 symbols. The names must be present in the Unitherm database as
components (species).
. Stoichiometric coefficients can be in an arbitrary format. They can
begin from any column starting at the position equal or greater than the
16-th position from the beginning of the reactant name (see above). At
least one space is required between the species name and the
stoichiometric coefficient.

Note: R2K recognises an additional type of reactant that is absent from
the Unitherm database - the electron. If you need to write a redox half-
reaction, just use "e-" for the electron name.


Running R2K

Since the utility has no user interface, you need to define the working
folder for the program before you start it. This can be done by editing its
shortcut property "Working folder" (or "Start in", depending on your
system).

Before running R2K, make sure it will find the right copy of the Unitherm
database. The path to the database is specified in the initialisation file
R2K.ini.

Note: The program searches for its initialisation file in the working
(start-up) folder. However, if R2K.ini is missing, this file can be
substituted by the initialisation file for the UT2K utility (UT2K.ini
file) located in the same folder. In this case, R2K will use the UTpath
and D-H settings from UT2K.ini. This mode allows you to ignore the
necessity of the initialisation file R2K.ini if both utilities have the
same working folder and you are working on the same chemical system
using both utilities.

If these utilities have different working folders, you still can copy
your UT2K.ini file into the R2K's working folder if you do not want to
create R2K.ini with the same settings manually.

The calculated log K values based on the data from the React.txt and
TPset.txt files will be saved in the logK.txt file in the same working
folder.

Note: If required, files TPset.txt and React.txt can also be generated
by UT2K utility.


Program messages

While working, R2K may inform you about the occurred errors (e.g., if one
of the mandatory source files is not found in the working folder). Any of
these error messages stops the program without generating the output file.
If no critical errors occurred during the program execution, R2K will
generate the output file logK.txt with an appropriate notification. Note
that an older version of logK.txt located in the working folder will be
replaced without any notification.


Output file logK.txt

All the data in the output file logK.txt are self-explanatory. This file
includes:

. The title.
. The data obtained from the TPset.txt file: the table type and lists
of temperatures and pressures.
. Optionally, tabulated values of the parameters of the Debye-HÝckel
equation (A, B, and b-dot).
. Reaction records based on the React.txt file:
. The stoichiometry data block for a given reaction. Note that logK.txt
outputs reaction stoichiometry record in a different format compared
to React.txt. Each reactant is characterised by its stoichiometric
coefficient, name in the database, and chemical formula extracted from
Unitherm. The last (chemical formula) position is also allocated for a
diagnostic message in case of non-critical errors.
. The tabulated log K values for the given reaction. If R2K finds an
error in a reaction, the line immediately below the stoichiometry data
block will contain the message that the reaction is not processed. In
this case, the log K table will not be printed.

Error messages


Critical errors

R2K will attempt to inform you about every error that may occur during its
execution. Errors that do not allow the program to run further properly are
critical. In case of a critical error the program displays an error message
and immediately stops running. The list of the program's critical errors is
as follows:

|Error message |Reason and recommendation |
|Unitherm database not |Initialisation file is not found or its Utpath |
|found |parameter is erroneous. Check the R2K.ini file |
| |(or, optionally, the UT2K.ini file). |
|Cannot read database |The version of the Unitherm database you are using|
|of a higher version |is higher than the version of this utility. Use a |
| |database with an earlier version number. |
|File ... not found |The working folder does not contain one of the two|
| |mandatory input files (TPset.txt or React.txt). |
| |Put the required file into the working folder. |
|Error(s) in file ... |Incorrect structure or unrecognised line in the |
| |specified input file. Edit the file. |
|Syntax error in |Incorrect list of temperatures in the input file |
|temperatures |TPset.txt. Check the temperature list. |
|Syntax error in |Incorrect list of pressures in the input file |
|pressures |TPset.txt. Check the pressure list. |
|Too many temperatures |The number of temperatures in the input file |
| |TPset.txt exceeds the maximal value (21). Reduce |
| |the temperature list. |
|Too many pressures |The number of pressures in the input file |
| |TPset.txt exceeds the maximal value (7 for the |
| |tables of the "grid" type; also, see below). |
| |Reduce the pressure list. |
|Temperature out of |One or more temperatures have invalid value |
|range |(should be within the 0-1000 ºC range). Remove |
| |invalid values. |
|Pressure out of range |One or more pressures have invalid value (should |
| |be within the 0-5000 bar range). Remove invalid |
| |values. |
|Number of temperatures|For tables of the type "path" each calculation |
|and pressures |point must be defined by a pair of temperature and|
|inconsistent |pressure. Thus, the number of temperatures must be|
| |equal to the number of pressures. Check the table |
| |definition in the file TPset.txt. |
|Wrong format of |A critical error occurred while parsing reaction |
|reaction file |records from the React.txt file. As reactions are |
| |processed subsequently, the results for the |
| |successfully processed reactions are written in |
| |the output logK.txt file. View logK.txt to find |
| |the reaction that resulted in this error. |
|Unexpected error |An error that should not occur in a correct |
| |system. A possible reason for this error is an |
| |error in the Unitherm database. Please inform the |
| |utility developer (Yuri Shvarov, |
| |yshvarov@geol.msu.ru) if this error occurred |
| |because of any other reason. |


Non-critical errors

Non-critical errors make it impossible to tabulate the log K values for the
current reaction but allow processing of the subsequent reactions. If an
error is detected in a reactant, the corresponding diagnostic message is
printed in the chemical formula field for this species. If the error
pertains to the whole reaction, the appropriate message is printed in the
line immediately below the reaction stoichiometry block. In both cases, the
log K table is not built and the notification "Reaction not processed" is
added to the line below the reaction stoichiometry block.

|Error message |Location |Meaning and recommendation |
|Unknown |Chem. |Internal database error. Check the UT database|
|reactant type |formula |files. |
| |field | |
|Species not |Chem. |There is no species with this name in the |
|found |formula |database. Verify spelling of the species' name|
| |field |in the React.txt file |
|Error(s) |1st line |Summary message. Notifies the presence of one |
|detected |below the |of two above messages. |
| |reaction | |
| |stoichiome| |
| |try record| |
|Incorrect |1st line |The formula of an aqueous species from the |
|formula |below the |Unitherm file UT_frmls.ref is incorrect. Check|
|occurred |reaction |the formula in this file. |
| |stoichiome| |
| |try record| |
|Reaction not |1st line |Found a non-zero sum of mole quantities of an |
|balanced |below the |element or charge for the reaction. Check the |
| |reaction |reactant names, their formulas, and |
| |stoichiome|stoichiometric coefficients. |
| |try record| |
|*error* |Log K |This message is printed in the log K table |
| |table |instead of a value that could not be computed |
| | |correctly (usually, in an extrapolation area).|
| | |No action is required, as calculated constants|
| | |have no physical sense in these areas. |