Calculation of the P and As activity coefficients in In-P and In-As mixtures with the regular solution approaches and lattice models

The activity coefficients of P and As in the mixtures of In-P and In-As are calculated along the liquidus curve in the concentration ranges 0.014 <= xsub(p) <= 0.45 and 0.019 <= xsub(As) <= 0.87 using different versions of the regular solution theory and the lattice models of Barker and Tompa. It is shown that the Simple Solution, the Subregular Solution, and the model of Barker with temperature-dependent interaction parameters give a satisfactory description of the experimental variation of the activity coefficients and liquidus temperatures for both systems. (author)