Electronic Band Structure of Cadmium Chromium Chalcogenide Spinels: CdCr2S4 and CdCr2Se4

We report ab initio band structure results for two chromium chalcogenide spinels, CdCr2S4 and CdCr2Se4. Electronic structures have been calculated for both the nonmagnetic and the ferromagnetic states. The calculations correctly predict CdCr2Se4 to be a ferromagnetic insulator. The results for CdCr2S4 correspond to a ferromagnetic semimetallic ground state, with very low density of states at the Fermi energy and a nearly gapped structure. Strong exchange splitting in both compounds suggests the possibility of realizing a half-metallic ferromagnetic state in doped Cr chalcogenide spinels.