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displays on the screen the current status of the system in terms of:

(a) which elements, components, substances, unaries and phases are to be considered in the calculations
(b) various parameters set by the user

  • the amounts of Type 1 components

  • the fixed activities or partial pressures of Type 2 components

  • the range of Type 3 components

  • the settings of gas volume and temperature






list system = elements substances !

list system = components settings phases !

Parameter values:


ELEMENTS displays a list of elements present in the chosen system. This may be useful if the components are non-elemental.

COMPONENTS The word components has two distinct meanings in COPLOT, namely the predefined components and the effective components. The effective components are those determined by the user by means of the SET and RANGE commands. They can be examined using LIST SYSTEM SETTINGS. The predefined components are determined by the initial data retrieval. If the systems has been defined using DEFINE SYSTEM. then the predefined COMPONENTS are the elements or compounds specified in the system definition, for example as in the following list:

    1      Cu                      NORMAL     undefined
    2      S                       NORMAL     undefined
    3      H2O                     NORMAL     undefined
    4      H/+                     NORMAL     undefined
    5      O                       NORMAL     undefined

The 3rd and the 4th column headings need some explanation. The STATUS column can have the entries NORMAL/ABSENT. NORMAL (i.e. present) and ABSENT indicate whether the component is included in the system, irrespective of the original DEFINE SYSTEM command - this adjustment is made using the CLASSIFY option. However CLASSIFY ABSENT has not been fully tested for COMPONENTS in COPLOT. AMOUNT is the number of moles of each component present as determined by the user using the SET option. At least one component must have a set amount (see SET).

SUBSTANCES   displays the substances that could possibly be included in the calculations:

    1      Fe                      NORMAL
    2      Fe<g>                   NORMAL
    3      Fe2<g>                  NORMAL
    4      FeH<g>                  NORMAL
    5      FeHO<g>                 NORMAL
    6      FeHO2<g>                NORMAL
    7      FeH2O2<g>               NORMAL
    8      FeO<g>                  NORMAL
    9      FeO2<g>                 NORMAL
   10      H<g>                    NORMAL
   11      H2<g>                   NORMAL
   12      HO<g>                   NORMAL
   13      HO2<g>                  NORMAL
   14      H2O<g>                  NORMAL
   15      H2O2<g>                 NORMAL
   16      O<g>                    NORMAL
   17      O2<g>                   NORMAL
   18      O3<g>                   NORMAL
   19      FeHO2                   NORMAL
   20      FeH2O2                  NORMAL
   21      FeH3O3                  NORMAL
   22      Fe2H2O4                 NORMAL
   23      Fe0.947O<WUSTITE>       NORMAL
   24      FeO                     NORMAL
   25      Fe2O3<FE2O3_GAMMA>      NORMAL
   26      Fe2O3<FE2O3_HEMATITE    NORMAL
   27      Fe3O4<MAGNETITE>        NORMAL
   28      H2O<H2O1_LIQUID>        NORMAL
   29      H2O2<H2O2_LIQUID>       NORMAL

Substances are constrained to be NORMAL (present) when the system is initially DEFINED but,  they may temporarily be removed by reCLASSIFYing them as ABSENT. 

PHASES   displays all phases:

 NUMBER    PHASE                   STATUS      MODEL
    1      Fe                      NORMAL      PURE SUBSTANCE
    2      GAS                     NORMAL      IDEAL GAS
    3      FeHO2                   NORMAL      PURE SUBSTANCE
    4      FeH2O2                  NORMAL      PURE SUBSTANCE
    5      FeH3O3                  NORMAL      PURE SUBSTANCE
    6      Fe2H2O4                 NORMAL      PURE SUBSTANCE
    7      WUSTITE                 NORMAL      PURE SUBSTANCE
    8      FeO                     NORMAL      PURE SUBSTANCE
    9      FE2O3_GAMMA             NORMAL      PURE SUBSTANCE
   10      FE2O3_HEMATITE          NORMAL      PURE SUBSTANCE
   11      MAGNETITE               NORMAL      PURE SUBSTANCE
   12      H2O1_LIQUID             NORMAL      PURE SUBSTANCE
   13      H2O2_LIQUID             NORMAL      PURE SUBSTANCE

The entried under PHASE will often closely resemble the SUBSTANCE list. The reasons for this are as follows. Many pure condensed   substances are stored on the database without explicit phase names - for example NaCl may be stored as NaCl, rather than NaCl<halite>. COPLOT does not cater for substances that form non-ideal solutions and the program generates phase labels from the chemical formula when no explicit phase names are given. Thus, all condensed substances without secondary phase labels must form separate phases. This does not apply to gases or aqueous solutions, which all belong to these same phases, irrespective of the  secondary label, which, in the case of gases, identifies isomeric forms.
In  principle, as with SUBSTANCE, each phase can be CLASSIFY'd as NORMAL (present) or ABSENT. In practice, in COPLOT it is useful to classify absent only SUBSTANCES rather than PHASES or COMPONENTS.
The MODEL column indicates how the program deals with interactions between substances in the same phase. In the examples above,  PURE CONDENSED indicates a stoichiometric substance, i.e. no solution. Neither the IDEAL GAS nor the IDEAL AQUEOUS models allow non-ideal interactions.

SETTINGS displays user-defined conditions for which the calculations will be performed:

 TEMPERATURE       :   1000.000
 PRESSURE/Pa       :   101325.0
 VOLUME/m3         :    undefined
 SYSTEM AMOUNT/mol :    undefined
 COMP. AMOUNTS/mol :  0.1000000E-05   2.000000       0.000000       0.000000
 COMP. AMOUNTS/mol :  0.1000000E-01
 SYSTEM MASS/kg    :    undefined
 COMP. MASSES/kg   :  0.5584500E-07  0.2015880E-02   0.000000       0.000000
 COMP. MASSES/kg   :  0.3206500E-03

 Fe<g>                 0.1000000E-05
 H2<g>                  1.000000
 S<g>                  0.1000000E-01

 X        O2<g>                  -30.000   to        2.000
 Y        ClH<g>                 -10.000   to        2.000

Although for compatibility with other modules reference to composition by mass will be found in the SETTINGS list, mass has little significance in predominance area diagrams.

ALL Entry of ALL is equivalent to entry of COMPONENTS SUBSTANCES ELEMENTS PHASES UNARIES SETTINGS. All are listed.

General comments:

The information provided by LIST is important for use with the CLASSIFY command, and particularly with the SET and RANGE commands.

(a) the  quantities of Type 1 components are set by referring to a substance name without a phase label.

(b) SET or RANGED potentials (molality, activity or partial pressure)  are assigned by quoting the substance name with a phase label or the substance number. Substances that are SET by potential are referred to as Type 2 components; substances that are given a RANGE become Type 3 components.

For a system defined by the SYSTEM parameter, the substance number, substance name and phase label may be obtained from LIST SYSTEM SUBSTANCES. 

Although parameter values can be given in any order, the output from LIST is in a fixed sequence.


Updated 6 July 2010