The diffusion of He atoms and small He clusters in Ti at various temperatures were simulated. The pre-factors and the activation energies for diffusion were calculated. It was concluded that the diffusion was anisotropic. Simulations showed that pre-factors for diffusion were different to those of He species diffusing in different directions, but the activation energies were the same. The result demonstrated that it was insufficient to predict the diffusion behavior of He in metals when only the energy barrier in static lattice was considered. Dynamic calculations were necessary in order to obtain the correct pre-factors.

Molecular Dynamics Study of Small Helium Cluster Diffusion in Titanium. Chen, M.: Acta Physica Sinica, 2011, 60[12], 126602