It was recalled that the lightweight complex metal hydrides, NaH and LiH, were

the last-step materials during the hydrogen release process of alanates and borates.

First-principles molecular dynamics calculations were performed, based upon

density functional theory, ir order to study the hydrogen-deuterium exchange in

NaH and LiH. Single hydrogen-deuterium exchange in NaH and LiH was predicted

and the self-diffusion constants were calculated to be: <D>NaH ≈ 1.46 x 10−9m2/s of

deuterium in NaH at 420K and <D>LiH ≈ 1.49 x 10−9m2/s of deuterium in LiH at

550K; in good agreement with experiment.

Ab Initio Molecular Dynamics Study of the Hydrogen Diffusion in Sodium and

Lithium Hydrides. M.Ramzan, R.Ahuja: Journal of Applied Physics, 2009, 106[1],

016104