Finite difference methods were used to calculate the transient and steady-state diffusion behavior of H atoms permeating through films of finite thickness and out-gassing from uniformly charged spheres. The relationships between the lattice diffusivity obtained from defect-free materials, and the diffusivities obtained from samples containing vacancy-related trapping sites and metastable (dislocation-related) traps, were calculated.

The Transient Diffusion of Hydrogen in Finite Metal Films and Spheres Containing Trapping Sites. D.Zang, R.B.McLellan: Journal of Physics and Chemistry of Solids, 2002, 63[1], 43-56