Abstract
The self-consistent band structure of the layer crystals NiCl2, CoCl2, FeCl2, and MnCl2 has been calculated by the intersecting-spheres model, using both the Slater and the Gáspár-Kohn-Sham approximation of the exchange potential. The results of these calculations, when compared with the experimental data and with previous results obtained for MgCl2, provide a rough and qualitative but reasonable interpretation of the various x-ray and optical spectra of these materials.