SEMIEMPIRICAL CALCULATION OF CADMIUM CHALCOGENIDE CLUSTERS

The electronic structure of cadmium chalcogenide clusters is calculated within the molecular orbital framework using the extended Huckel technique with charge self-consistency. The size of clusters calculated corresponds to one to three elementary cells (the largest cluster is Cd54S63). The results of the calculation show the tendency towards semiconductor-like band-structure formation. Explicit bands in the energy spectrum appear for clusters containing more than 100 atoms. There is good correspondence to experimental features of clusters in the optical and x-ray photoelectron spectra. The relative stability of clusters with different geometries and sizes is evidence of possible structure transformations in the case of small clusters. Most stable structures of small clusters are distinct from the bulk.