AMEND_ELEMENT_DATA

This command is for the Gibbs Energy System (GES) module.

The data for an element (in the SER, the Stable Element Reference, state) can be changed by this command. It should only be used for the elements that do not have any data in the database because the element data available in the database is set by the database-developer for the purpose of internal consistency. Except for the mass, the other values have no influence on the calculations.

Syntax

AMEND_ELEMENT_DATA

Prompts

Element name: <Element name>

Specify the name of the element for which you want to change the data.

 

New stable element reference /ABCD/: <Name of ser>

Press <Enter> to accept the default SER or specify a new SER for the element. Important: The default name should not be changed if this data is retrieved from a database. This name is used when parameters for a phase are listed and the database assumes that the stable element reference is the same as in the database. Only if the element's data have not been fetched from a database, e.g. entered manually, can you enter a new SER.

 

New atomic mass /xx.xxxx/: <yyyyyy>

Press <Enter> to accept the default atomic mass or specify a new value for the element. The atomic mass of the element is given in g/mol.

 

New h(298.15)-h(0) /xxx.xxx/: <yyyyy>

Press <Enter> to accept the default H(298.15)-H(0) or specify a new value for the element. H(298.15)-H(0) is the enthalpy difference between 298.15 K and 0 K for the element in its SER state.

 

New s(298.15) /xx.xxxx/: <yyyyy>

Press <Enter> to accept the default S(298.15) or specify a new value for the element. S(298.15) is the absolute value of the entropy at 298.15 K for the element in its SER state.

 

Default element reference state symbol index /#/: <index>

The index only changes the symbol, not any value. Normally the index is set correctly by the database. Only when manually entering data, you must set the index to get the correct symbol.

Specify an index for the default listing parameters (symbol), or press <Enter> to accept the pre-set index. 0 is for G, 1 is for H298 and 2 is for H0.

The index is to define the symbol printed in parameter listings. The symbol can be:

  • G the data are referred to Gibbs energy at a variable temperature (also called lattice stability).
  • H298 the data are referred to the enthalpy of the element at 298.15 K and 1 bar.
  • H0 is the same as H298 but at the temperature 0 K.