Ultraviolet properties and band structure of SnS₂, SnSe₂, CdI₂, PbI₂, BiI₃and BiOI crystals

The authors have conducted reflectivity measurements of the layer materials SnS 2 , SnSe 2 , CdI 2 , PbI 2 , BiI 3 and BiOI between 8 and 40 eV. Band structures have been calculated for SnS 2 , CdI 2 , PbI 2 on the basis of an LCAO approach and these are compared with the experimental data. Transitions from the metal d core states are discussed in terms of an atomic-like picture.