The diffusion of Cu in samples of various stoichiometries was studied by using radiotracer methods after surface deposition from solution. Annealing was carried out at 250-480C. The data could be described by:

D (cm2/s) = 1 x 10-3 exp[-0.7(eV)/kT]

O.E.Panchuk, V.I.Grytsiv, D.P.Belotskii: Izvestiya Akademii Nauk SSSR – Neorganicheskie Materialy, 1975, 11[10], 1763-5