Ab initio study of small gold clusters

The most stable geometries (lowest energy configurations) as well as the lowest-lying isomers of Au(n), n = 2-6, clusters are determined through ab initio calculations of the cluster total energy. It is found that Hartree-Fock plus second-order perturbation method of Moller-Plesset combined with a double-zeta basis set and an 11 valence electrons relativistic pseudopotential provide reliable results for a qualitative and quantitative analysis of the structures. Two-dimensional planar configurations are obtained as the lowest energy structures for all the gold cluster sizes investigated. Vibrational frequencies for all the investigated isomers were obtained. (C) 1999 Elsevier Science B.V. All rights reserved.