Theoretical studies of structural and electronic properties of AlnAsn clusters

We present theoretical results of size dependent structural, electronic, and optical properties of ligand-free stoichiometric AlnAsn clusters of zinc-blende modification. The investigation is done using a simplified parametrized linear combination of atomic orbital-density functional theory-local density approximation tight-binding (LCAO-DFT-LDA-TB) method and consider clusters with n up to around 100. Initial structures have assumed as spherical parts of infinite zinc-blende structure and then allowed to relax to the closest local-energy-minimum structure. We analyze the radial distributions of atoms, Mulliken populations, electronic energy levels (in particular, HOMO and LUMO), bandgap, and stability as a function of size and composition. (c) 2005 Wiley Periodicals, Inc. Int J Quantum Chem 106: 887-893, 2006