An Isotropic Empirical Intermolecular Potential for Solid H2 and D2: A Classical Molecular Calculation.

We develop an isotropic empirical potential for molecular hydrogen (H₂) and deuterium (D₂) by fitting to solidstate data, which is appropriate for classical molecular dynamics (CMD) approach. Based on the prior isotropic intermolecular potential used in self-consistent phonon approximation, a zero-point energy term and an embedded energy term are introduced to describe the H₂–H₂ and D₂–D₂ interactions in CMD simulations. The structure, cohesive energy and elastic properties of solid H₂ (D₂) are used as the fitting database. The present method is tested by calculating the melting point of solid H₂, and the pressure and bulk elastic modulus as a function of volume. The developed potentials well reproduce many properties of solid H₂ and D₂. [ABSTRACT FROM AUTHOR]