How relevant is the choice of classical potentials in finding minimal energy cluster conformations?

Abstract

We investigate the relevance of the choice of a particular classical potential in the task of finding global and local energy minima of small cluster conformations, in the context of their use as input for quantum refinement. We contrast results obtained using the many body Gupta and Sutton–Chen potentials for small nickel and copper clusters, with those of a Lennard-Jones pair potential. To obtain quantitative results we introduced a modified version of the concept of distance between configurations and color maps to represent these distances. Our main conclusion is that, for the small clusters we studied, all three potentials lead to practically the same results after quantum refinement is implemented.