Atomic and Molecular Hydrogen Impurities in Liquid 4 He

Abstract

The static properties of a single hydrogen atom and an hydrogen molecule in bulk superfluid4He are studied by means of the diffusion Monte Carlo method. The analysis includes atomic hydrogen, deuterium and tritium, and molecular hydrogen and deuterium. Our results, which show some differences with previous variational calculations, are in agreement with the only available experimental data corresponding to atomic deuterium. In contrast to the unbinding presented by the atomic impurities, the molecular ones do bind with energies higher than the chemical potential of pure4He.