Published online by Cambridge University Press: 10 February 2011
The hydrogen dynamics in LaHx was studied for different concentrations x ≥ 2.5 at different temperatures by quasielastic neutron scattering. The neutron spectra show the existence of both long-range translational diffusion and localized motion. The prefactor of the jump rate for the first process exhibits a maximum around x= 2.75. The radius for the second motion is in agreement with neutron powder diffraction measurements which support a localized motion of H confined in an octahedral site.