Properties of gold clusters and molecule-coated gold clusters as studied by molecular modeling

Abstract

The properties of small gold clusters are studied by use of density functional theory (DFT). A method validation study is conducted to choose a suitable DFT method. Geometry optimizations are performed on a number of different clusters, and their cohesive energies are computed. The charge distribution in the Au20 cluster is studied, both in the presence and absence of an electric field. The results are interpreted in terms of a model for the atomic charges in the cluster derived from electronegativity equalization. The interaction between Au20 and CO is studied, considering different possible adsorption sites on the face of the cluster. Only certain sites are found to give favourable interaction between the two subsystems.