<i>Ab</i> <i>initio</i> Hartree–Fock self-consistent-field molecular dynamics study of structure and dynamics of Li8

Abstract

An ab initio Hartree–Fock-based molecular dynamics scheme is formulated and applied to study structural and dynamical properties of the Li8 cluster. Three new locally stable isomers of the cluster—of a C3v, a Cs, and a D2d symmetry, respectively—are identified. The main emphasis is on exploring the cluster dynamics as a function of its energy. The simulations indicate that the cluster undergoes a solid-to-liquid-like transition as its energy is increased. An analysis of the transition is given at the level of detail which approximates that of studies utilizing semiempirical potentials. In particular, isomer-specific mechanisms of the phenomenon are described. The computational efficiency of the scheme is achieved through code optimizations and use of parallel processing. The approach is critically evaluated and directions of future work are outlined.