Vacancies and Diffusion in Solid Hydrogen

Abstract

Self-diffusion by a particle-vacancy exchange mechanism is investigated in solid hydrogen and deuterium. The calculations are based on our quantum-crystal formalism published previously. The self-diffusion coefficient is calculated as a function of temperature, and the results compared with values inferred from nuclear-magnetic-resonance measurements; agreement of theory and experiment appears to be satisfactory. The effect of pressure on diffusion is also considered.