Tight-binding method for Cu clusters; Ground state studies of Cu[sub 3]–Cu[sub 12]

The recently developed tight-binding parametrization of copper by Mehl and Papaconstantopoulos (I) is tested against the ab-initio Discrete Variational Method (DVM). Good agreement is found for the eigenvalues, and total energies. Next, this parametrization is used to perform Molecular Dynamics (MD) and simulated annealing in order to investigate the ground state structure of small copper clusters. In this study, clusters of size up to 12 were considered. Results concerning their ground state geometry, binding energy and HOMO-LUMO gap are reported and compared to available theoretical and experimental data.