Polarizabilities of isolated semiconductor clusters

The static polarizabilities alpha(c) of the isolated semiconductor clusters Si-N, GaNAsM, and GeNTeM have been investigated in dependence of cluster size and temperature. The results for the Si-N clusters are discussed within a two-band semiconductor model that includes a widening of the band gap due to quantum size effects. Additionally, the importance of defectlike electronic states is discussed for Si-N and GaNAsM clusters. The temperature dependence of the polarizability values for several GaNAsM and GeNTeM species gives evidence for vibronic (ionic) contributions to alpha(c).