The migration of H atoms in YH0.05 was investigated by means of electrical resistance measurements at about 150K. Disordered H atoms were introduced, by quenching from 273K into liquid N, and were then ordered by migration during annealing. The activation energy for H migration was deduced from a kinetic analysis of the resistance decrease due to ordering during isochronal or isothermal annealing. The magnitude of the energy could be determined more exactly by using isothermal annealing. Its value (0.481eV) was lower than that at high temperatures. The decrease was attributed to tunnelling effects.

K.Yamakawa, H.Maeta: Journal of Alloys and Compounds, 1999, 293-295, 341-5