The vibrational states, absorption energies, and diffusions of H in Pd and Pd1–xAgx (x = 0 to 1) were studied by first-principle calculations. All of the results compared favorably to experiment. The zero-point motion of H was important in the determination of the H site occupation, in the estimation of the diffusion barrier, and in the explanation of the reversed isotope effect. The interesting anomalous isotope effect was explored, and a diffusion mechanism was proposed for T. The preferred diffusion paths of H in Pd and Pd1–xAgx were “indirect” paths. According to the absorption energies and diffusion barriers, H diffusion in Pd-Ag alloys should avoid the Ag-rich areas.

Absorption and Diffusion of Hydrogen in Palladium-Silver Alloys by Density Functional Theory. X.Ke, G.J.Kramer: Physical Review B, 2002, 66[18], 184304 (11pp)