Quantum molecular dynamics simulations of hot, dense hydrogen

摘要

Quantum molecular dynamics simulations of pure samples and of mixtures of isotopic hydrogenic species (H, D, T) yield important structural, dynamical, and electronic properties that characterize matter at high compressions ( rho >= 0.25 g/cm3) and moderate temperatures (3000–60 000 K). Quantum mechanical treatments of the electrons, contained in periodically replicated reference cells of Na atoms, by density functional and tight-binding methods determine the force on the nuclei and the electronic structure of the medium. The nuclei move according to the classical equations of motion in response to this quantal force. In addition, pair potentials based on Thomas-Fermi models (Moliere) extend both the temperature and density range of the more sophisticated models. Comparisons of the models are presented together with a comprehensive description of the techniques. Examples over a broad temperature and density range illustrate the basic physics for a hot, dense hydrogen medium.