The proton spin-lattice relaxation rate, of H which was in solid solution in the hexagonal close-packed metal, was measured at temperatures ranging from 7 to 800K, and frequencies ranging from 12 to 400MHz. The value of the proton spin-lattice relaxation rate arose from conduction electrons, long-range and localized H motions, and from cross-relaxation by 175Lu nuclear spins. The conduction electron contribution (/s) was equal to T/148 at temperatures greater than 180K. Evidence for an electronic structure transition was seen at about 180K. Long-range H diffusion yielded a hopping frequency (/s) of the form: 2 x 1013 exp[-0.52(eV/atom)/kT].

D.R.Torgeson, J.W.Han, P.C.T.Chang, L.R.Lichty, R.G.Barnes, E.F.W.Seymour, G.W.West: Zeitschrift für Physikalische Chemie, 1989, 164[1], 853-8