ELECTRONIC STRUCTURAL AND MAGNETIC-PROPERTIES OF CADMIUM CHALCOGENIDEBERYLLOSILICATE SODALITES

Density functional self consistent spin-polarized calculations with th e Discrete Variational Method were performed to obtain the electronic structures of cadmium chalcogenide beryllosilicate sodalites Cd-8[BeSi O4](6)Z(2) and their bulk materials CdZ (Z = S, Se, Te). Similar as th eir bulk materials, these sodalites are also semiconductors. From thei r density of states and charge distributions, it was found that there is greater localization of the electron density in the sodalites compa red with that of the bulk. The band gaps in their bulk compounds are d ifferent from those in the sodalite structures due to the electrons of Si, Be and O filled in. Different from their bulk materials, the d el ectrons of Cd play an important role to form an unseparated valence ba nd with all orbitals of other elements. The calculated magnetic moment s of these three materials are very small since all d atomic orbitals are fully occupied.