Electronic structure of vacancy ordered spinels, GaMo₄S₈ and GaV₄S₈, from ab Initio calculations

Abstract

We report ab initio calculations for the band dispersions and total as well as partial densities of states for vacancy ordered, clustered spinels, GaMo₄S₈ and GaV₄S₈. Results are presented for the high temperature cubic phase for both compounds. Additionally, we discuss results of similar calculations for GaMo₄S₈ in an idealized cubic structure, as well as the nonmagnetic and the ferromagnetic states of the low temperature rhombohedral structure. Comparison of these results allows us to discuss the unusual aspects of the electronic structure of this interesting class of compounds, and provide estimates of the crystal-field and exchange splitting strengths.