Electronic structure of CuV2S4

The results of ab initio band-structure calculations and measurements of x-ray-emission valence spectra (XES) (Cu Lα, V Kβ5, V Lα, S Kβ1,3, S L2,3) and X-ray-photoelectron valence-band and core-level spectra (XPS) of CuV2S4 thiospinel are presented. It is found that a peak in valence-conduction bands close to the Fermi level is formed by V 3d states, which provide the metallic properties of CuV2S4. The valence band is formed by Cu 3d, V 3d, V 4p, and S 3p states. Examination of the XES and XPS results and the calculated charge-density maps and densities of states indicates that the valences of both Cu and V are similar to those of their elemental solids. Calculations show a strong electron-phonon coupling in CuV2S4 and the prospect of superconducting behavior has not been confirmed