Self-consistent phonon calculations and equations of state of solid hydrogen and deuterium

Abstract

A numerical computation of the ground-state energies and zero-temperature pressure-volume relations of fcc para-${\mathrm{H}}_2$ and ortho-${\mathrm{D}}_2$ was carried out within the framework of the self-consistent phonon approximation. The calculations employed two recently proposed pair potentials and are expected to be valid up to several hundred kilobars. The effect of the hard core in the intermolecular interaction was treated with a short-range correlation function. The pressure dependence of the phonon density of states, sound velocities, and bulk moduli were determined and comparison with experimental data was made where possible.