Pair Potential for Solid Rhodium from Extrapolated Ab-Initio Data

Abstract

The pair potential for solid rhodium is extracted from ab-initio energy-volume data using the lattice inversion procedure of Carlsson and co-workers [Phil. Mag. 41, 241 (1980)]. Because of the limited accuracy of the ab-initio techniques we extrapolate the energy for the low density systems by suitable analytical tail functions. We discuss the dependence of the molecular dynamics (MD) simulation results on the choice of the cohesive energy tail function. The MD-simulated radial distribution functions (RDFs), obtained for several energy tails, are compared with our experimental EXAFS results. We show that it is possible to choose the energy tail to achieve an excellent matching between the experimental and the MD calculated first RDF peak.