Electronic band structure of In2S3 and CdIn2S4 semiconductor spinels from the data of x-ray spectroscopy and theoretical calculations

The electronic band structure of the chalcogenide spinels In₂S₃ and CdIn₂S₄ has been studied using the FEFF8 program. It is shown that the valence band top is formed by the S p states mixed with the In s and In p states for In₂S₃ or with the Cd s, Cd p, In s, and In p states for CdIn₂S₄. Compared to In₂S₃, the presence of Cd atoms in the nearest environment of S atoms in CdIn₂S₄ does not considerably affect the electronic band structure. In CdIn₂S₄ the Cd 4d states, as well as the In 4d states, form a narrow localized band shifted deep into the valence band. The theoretical results are in good agreement with the experimental x-ray photoelectron and x-ray spectra.