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MTDATA Configuration Variables

Set in the file mtsignon.txt at the start of an MTDATA session in MTDATA version 4.71 and earlier.



To make changes during an MTDATA session enter [ before the variable name (in the character interface)



[? lists the settings currently active.

Variable names and values must be UPPER CASE in versions of MTDATA before 4.60.

Examples of "configuration variables"

HISTORY Provides information about the current MTDATA session eg MTDATA version number, log file name etc
DEBUG Reports all subsequent file opening and closing operations to the screen
Gives the CPU time used during the current MTDATA session or resets the CPU_TIME to zero
Sets the number of lines to a page in output from the LIST command. NONE gives continuous scrolling
Establishes the interactive graphics terminal type. (See mtsignon.dem for more information)
Switches between vertical and horizontal formats for MTDATA menus
BACKGROUND 24 Controls the colour of the background of the MTDATA graphics screen. (See mtsignon.dem for more information)
FOREGROUND 15 9 10 12 14 13 Controls the colours of lines drawn on the MTDATA graphics screen. (See mtsignon.dem for more information)
Used to set screen colours for normal MTDATA text output, error messages, menus, help, and major errors respectively. (See mtsignon.dem for more information)
IMPLICIT_COMPONENT=<NAME> Adds a named component to the end of EVERY database search list. eg DEFINE SYSTEM "H,Cl" ! would cause MTDATA to search for all combinations of H, Cl and /-if the named component was /-. IMPLICIT_COMPONENT=AUTOMATIC causes a suitable charged implicit component to be selected automatically if needed. IMPLICIT_COMPONENT=NONE cancels any previous implicit component settings. The default setting is IMPLICIT_COMPONENT=AUTO
ISO_SMALL_DOTS=YES/NO Specifies whether small or large dots should be used as a progress indicator in calculations using the isolpeth.mac “built-in” application. The default is YES
ISO_LINE_LABELS=YES/NO Specifies whether the lines calculated by NEW_ISOPETH are labelled automatically. The default is NO.
SUBLATTICE=SIMPLIFY Replaces sublattice models by simple substitutional models where possible for computational efficiency. Sublattice models can be retained by specifying SUBLATTICE=NOCHANGE
MISSING_DATA=FAIL (or CONTINUE) Establishes the action to be taken if missing binary interactions are identified during a database search. MTDATA will either CONTINUE and treat the missing interactions as ideal or FAIL to create a valid datafile
SYSTEM_RESIZE=<number>/NONE Specifies that all subsequent calculations should be performed with a system automatically resized to the specified number of moles (between 1 and 10000 inclusive). Results are reported according to the system specification with no RESIZE in operation. Use of SYSTEM_RESIZE is important in calculations where system sizes may become very small such as in SCHEIL calculations
HCPY=HPGL("start plot";"end plot")
Used to identify the type of hard-copy output to be generated during the current MTDATA session. Pre-plot and post-plot control code sequences may be supplied to control paper feeding and printer modes. (See mtsignon.dem for more details)
Used to specify the type of paper to be used for hard-copy output and so ensure MTDATA diagrams are positioned correctly
MAX_CHAR=<number> Used to specify the maximum number of characters per line in tables of results generated from within MULTIPHASE
In BATCH mode no cursor input is expected from the user and graphics screens are cleared automatically without the need for a . INTERACTIVE is the normal MTDATA mode
MACRO=CONTINUE Seen in MTDATA log files. Allows a macro to continue to execute following minor errors (such as typing mistakes made during an MTDATA session)
PREFIX=<path> Used to point to the central MTDATA folder where menu files, help files etc are to be found
DATABASE_PREFIX=<path> Used to point to the MTDATA folder where databases are to be found
METAFILE=filename (Use FILE, SAVE AS in MTDATA for Windows)
PARAMS_BRIEF=NO/YES Used in the ASSESSMENT module to control whether the data for the first two terms only of the temperature expansion are listed (YES) or all the coefficients (NO). The default value is YES


This is used to select the strategy to search for miscibility gaps. The default setting is NEW and in this mode interactions or unaries which have been specifically marked as potentially responsible for a miscibility gap are used to generate specific trial starting points for repeat caclulations to find the solution which gives the lowest Gibbs energy. If OLD is selected every unary in the phase is defined as a trial starting point for the calculations - this is likely to be slower than the NEW strategy but potentially more reliable.
MORE_MISC_GAP=YES/NO If selected (YES) extra calculations are carried out to check the validity of the original calculated result. The method involves doing a run then classifying absent phases found to be present one at a time and checking whether a lower Gibbs Energy has been found. The method also varies from the existing method in that it classifies absent non miscibility gap phases in some iterations and does the old miscibility gap restarts on reduced systems. Therefore it may or may not be faster on large systems. The default setting is NO
CHEMICAL_ORDERING=ABSENT/NORMAL The default value is ABSENT. This automatically classifies a chemically ordered phase as absent on creating an mpi file when searching a database. If the value is classified as NORMAL the chemically ordered phase will be appear in the mpi file as NORMAL
DEBYE-HUCKEL=YES/NO/UNDEFINED By default dilute aqueous data are treated as ideal aqueous solutions (value NO). A more realistic Debye-Huckel may used by selecting YES. This Debye-Huckel model without additional interactions (eg Pitzer model) may give spurious results in very concentrated solutions. If UNDEFINED is selected the Debye-Huckel model is used if any interactions
SEARCH=NO_PLASMA/ALL By default data for charged species for crystalline phases are retrieved automatically during a database search if IMPICIT_COMPONENT has been set to automatic. Data for charged gaseous species are not retrieved. It is possible to retrieve data for the gas phase, which may contain a large number of charged species, as well as those for crystalline phases by setting the configuration variable SEARCH to ALL.
PHASE_PRESENT_REL_TOL=UNDEFINED/<value> This is used as a criterion to select whether a phase is deemed to be present during a calculated equilibrium. Its effect will depend on the sort of calculation being carried. SYSTEM_RESIZE is generally a more sensible parameter to adjust to optimise accuracy
TIDY_COMPUTE=YES/NO This initiates an extra calculation at the end of a compute removing all those phases calculated to be absent in the initial calculation. The default value is NO

Updated 31 May 2011