Room-Temperature Thermal Conductivity and Grüneisen Parameter of the I–III–VI2 Chalcopyrite Compounds

Abstract

The Grüneisen parameter (γ) of the I–III–VI2 chalcopyrite compounds is calculated from the reported room-temperature thermal conductivity (χ) data using a modified form of the Leibfried and Schlömann theory that takes into account the effect of the crystal structure. It is also found that γ varies linearly with the Phillips average bond ionicity in these compounds. The values of γ obtained after these corrections are in good agreement with those obtained from other methods. It is also established that for compounds of low cation-anion mass ratio, χ at room temperature is appreciably influenced by the acoustic-optical three-phonon scattering.