The structure of the liquid alkali metals

Abstract

We present calculations of the structure of the liquid alkali-metals, based on the optimized random phase approximation and on effective interatomic pair potentials derived from pseudopotential perturbation theory. In our approach the atomic interactions are decomposed self-consistently into a repulsive short-ranged part and a weak long-range perturbation, the repulsive part being modelled by a hard-sphere reference system via the Weeks-Chandler Andersen functional expansion. We show detailed comparisons with computer-simulation data and with experiment, demonstrating that the optimized random phase approximation with a hard-sphere reference system applies equally well to the liquid alkali metals as to the liquid polyvalent metals. Thus it is a comprehensive description of all liquid simple metals from Li to Pb.