Thermodynamic Properties of the Molten Tl-GeTe_4 System

摘要

Form the electromotive force method, the chemical potential or activity of Tl in the molten Tl-GeTe_4 system has been measured as a function of composition and temperature. The chemical potential of Tl has then been separated in terms of partial entropy and enthalpy, the both quantities showing an abrupt change from negative to positive values around the stoichiometric composition corresponding to Tl_8 GeTe_4. The integral molar entropy and enthalpy, △S_m and △H_m, show sharp minima at the composition Tl_8GeTe_4 where the electrical conductivity has a sharp imimum and the thermoelectric power changes its sign.