From known Gibbs free energies for the magnesium-hydrogen system, the concentration, x, of hydrogen in MgHx - in equilibrium with MgH2 - was calculated to be 1.13 x 10-3 at 673K. From an ab initio dynamic simulation the position of hydrogen in magnesium (mainly in tetrahedral sites), the Debye-Waller factors (0.06Å2 for tetrahedral sites and 0.08Å2 for octahedral sites) were obtained. The diffusion constant was 6.6 x 10-9m2/s at 673K.

Hydrogen Diffusion in Magnesium Metal (α Phase) Studied by ab initio Computer Simulations. H.G.Schimmel, G.J.Kearley, J.Huot, F.M.Mulder: Journal of Alloys and Compounds, 2005, 404-406, 235-7