Electronic band-structure calculations of some magnetic chromium compounds

Band-structure calculations of CrS, CrSe, Cr₃Se₄ and CrSb are presented. Together with the accompanying results for the chromium tellurides, these calculations give a coherent picture of the changes in the electronic structure caused by anion substitution and by introduction of cation vacancies. The importance of the Cr-X covalency and the 3d(_z²)-3d(z²) overlap of Cr neighbours along the c axis is stressed. Further, the bandstructure calculations shed some light on the formation, the variation in magnitude and the coupling of the Cr magnetic moments and the indirect magnetic polarisation of the anion bands.