A Simplified Procedure to Estimate Thermodynamic Activities in Multicomponent Oxide Melts

摘要

A model is presented by which thermodynamic activities of multicomponent oxide melts can be estimated to an accuracy of approx. 0.3 on the log activity scale. The calculation procedure is comparatively simple: Firstly, the constitutional compounds of the respective melt are identified by a unified norm calculation similar to the C.I.P.W. norm used in geology. Then, the activities of individual oxides are obtained by linear combinations of the Gibbs free energies of formation of these compounds (from the oxides), and the Gibbs free energies of the respective oxides under consideration. The results match well with available experimental data from binary and ternary systems, and a commercial mass glass composition.