The diffusion of hydrogen atoms in solid palladium was studied via molecular dynamics simulation. In this calculation, the palladium atoms were fixed on the sites of the face-centered cubic lattice and the hydrogen atoms were initially put on the O (octahedral) sites. Using the present molecular dynamics simulation, the diffusion constant and activation energy were calculated for several different concentrations of hydrogen atoms. It was found that the hydrogen atoms exhibited jump motions between the O sites which led to super-diffusion in the solid palladium. The temperature dependence and concentration dependence of the vacancy factor and jump correlation functions were also obtained.

Molecular Dynamics Study of the Diffusion of Hydrogen in Solid Palladium. Muranaka, T., Uehara, K., Takasu, M., Hiwatari, Y.: Molecular Simulation, 1994, 12[3-6], 329-41