The self-diffusivity of H in the body-centered cubic VHx phase was measured for x-values ranging from 0.17 to 0.68, and temperatures of 435 to 620K, by using the nuclear magnetic resonance alternating pulsed field spin echo method. It was found that the results could be described by Arrhenius relationships in which the activation energy depended markedly upon concentration, while the pre-exponential was essentially constant:

x =0.17:     D (cm2/s) = 4.3 x 10-4 exp[-0.087(eV)/kT]

x =0.22:     D (cm2/s) = 4.0 x 10-4 exp[-0.089(eV)/kT]

x =0.31:     D (cm2/s) = 3.8 x 10-4 exp[-0.089(eV)/kT]

x =0.38:     D (cm2/s) = 4.4 x 10-4 exp[-0.106(eV)/kT]

x =0.51:     D (cm2/s) = 5.2 x 10-4 exp[-0.121(eV)/kT]

x =0.68:     D (cm2/s) = 4.7 x 10-4 exp[-0.132(eV)/kT]

J.E.Kleiner, E.H.Sevilla, R.M.Cotts: Physical Review B, 1986, 33[10], 6662-5