Liquid arsenic: Comparison of ab initio and pair-potential predictions of molecular structure

Properties of liquid arsenic are calculated by molecular-dynamics simulations using both ab initio local-density functional theory and pair potentials based on second-order perturbation theory. Radial distribution functions from both procedures compare well with experiment, in spite of small but significant differences in short-range order between the two calculations. Coordination is predicted to evolve from three-fold to six-fold when density is increased, and optical properties are predicted.