Semi-empirical potentials for He-He and He-V interactions were calculated on the basis of a theoretical model for a metal crystal. This model included contributions from 2-body components of atomic interactions, and the s- and d-electrons, into the binding energy of a transition metal. Using molecular dynamics methods, the equilibrium properties (energies, entropies, relaxation volumes, etc) were calculated and the atomic configurations of clusters (containing up to 15 He atoms and up to 3 vacancies) having the minimum free energy of formation were determined. The most probable mechanisms of He clustering and diffusion were deduced.

Atomic Mechanisms and Energetics of Thermally Activated Processes of Helium Redistribution in Vanadium. V.M.Chernov, V.A.Romanov, A.O.Krutskikh: Journal of Nuclear Materials, 1999, 271-272, 274-9