COMPOUND_PHASE
COMPOUND_PHASE [phase name]*24 [data-type code]*8 [constituent] !
The keyword is a compact way to simultaneously define a species, a compound phase (maximum 24 characters) and its phase-constituent. It is useful for stoichiometric phases with constant compositions. The species name and stoichiometric formula must be identical, i.e. being the given constituent. The phase has this species as its only constituent. This keyword allows the database definition file for a large substance database to be more compact; it is a combination of the SPECIES, PHASE and CONSTITUENT keywords.

COMPOUND_PHASE AL2O3 % AL2O3 !
COMPOUND_PHASE MAGNETITE %MF FE3O4 !
COMPOUND_PHASE QUARTZ % SIO2 !