Secondary ion mass spectroscopy was used to study the volume diffusion of Cu in 4N-purity Ag crystals. At 699 to 897K, the results were described by:

D (cm2/s) = 2.9 x 10-2 exp[-39(kcal/mol)/RT]

P.Dorner, W.Gust, M.B.Hintz, A.Lodding, H.Odelius, B.Predel: Acta Metallurgica, 1980, 28[3], 291-300