Thermodynamic behaviour of zinc and cadmium in liquid-Te-saturated CdTe---ZnTe solid solutions

Abstract

The activity of zinc in liquid-tellurium-saturated CdTe---ZnTe solid solutions in the temperature range 743-848 K was measured by an electrochemical technique using LiCl--- KCl + 5 wt% ZnCl₂ as the molten salt electrolyte. The activity of cadmium was estimated from hypothetical e.m.f. values and also by Gibbs—Duhem integration. The activity values of Zn and Cd calculated at different temperatures were used to obtain various partial and excess molar thermodynamic quantities, namely ΔG̅^M_Zn, ΔG̅^XS_Zn, ΔH̅^M_Zn, ΔS̅^M_Zn, ΔS̅^XS_Zn, ΔG̅ ^M_Cd, ΔG̅^XS_Cd, ΔH̅^M_Cd, ΔS̅^M_Cd and ΔS̅^XS_Cd. The thermodynamic data obtained in the present investigation are consistent with the view that the CdTe---ZnTe system consists of a single phase throughout the entire range of composition.