First-principles calculations were used to identify the defects that were relevant to

H transport in MgH2 and NaMgH3. In both materials, the physically relevant

defects were charged, and the H diffusion was dominated by the mobility of

negatively charged H interstitials. The diffusion of these species occurred via

concerted interstitialcy mechanisms with low energy barriers. The results indicated

that any examination of H diffusion in light-metal hydrides had to consider the

concerted diffusion of charged defects.

Hydrogen Diffusion in MgH2 and NaMgH3 Via Concerted Motions of Charged

Defects. S.Hao, D.S.Sholl: Applied Physics Letters, 2008, 93[25], 251901