Thermal Expansion and Thermal Conductivity of (In₂S₃)_x(AgIn₅S₈)_{1 – x} Alloys

Abstract

The thermal expansion and thermal conductivity of In₂S₃ and AgIn₅S₈ single-crystal compounds and (In₂S₃)_x(AgIn₅S₈)_{1 – x} alloys grown by the Bridgman method are studied. It is established that the thermal-expansion coefficient linearly varies under changes in the composition parameter x and the thermal conductivity has a minimum for the equimolar composition. From experimental data on the thermal-expansion coefficient, the Debye temperature and the root-mean-square (rms) dynamic displacements of atoms are calculated. It is shown that, as the content of Ag atoms in the alloys is increased, the Debye temperature increases and the rms dynamic displacements of atoms in the crystal lattice decrease.