Size-dependent properties of ZnmSn clusters:: A density-functional tight-binding study -: art. no. 044311

We present the results of our theoretical calculations on structural and electronic properties of ligand-free ZnnSn [with n ranging from 4 to 104 (0.8-2.0-nm diameter)] clusters as a function of size of the clusters. We have optimized the structure whereby our initial structures are spherical parts of either zinc-blende or wurtzite structure. We have also considered some hollow bubblelike structures. The calculations are performed by using a parametrized linear combination of atomic orbitals-density-functional theory-local-density approximation-tight-binding method. We have focused on the variation of radial distribution function, Mulliken populations, electronic energy levels, band gap, and stability as a function of size for both zinc-blende and wurtzite-derived ZnS clusters. We have also reported the results of some nonstoichiometric ZnmSn (with m+n=47, 99, 177) clusters of zinc-blende modification. (C) 2005 American Institute of Physics.