Substitutional Ag probe atoms were created by transmutation-doping, using radioactive Cd isotopes. The lattice sites of the Ag isotopes were determined by measuring the channelling effects of emitted conversion electrons. At temperatures below ambient, the Ag occupied mainly substitutional lattice sites. With increasing temperature, the substitutional fraction of the Ag atoms decreased. It completely vanished at temperatures above 400K. A simultaneously measured loss of Ag activity indicated that some of the Ag preferentially diffused to the surface, and there disappeared. The remaining Ag was thought to be trapped at extended defect complexes or precipitates. In the case of Cd-rich material, it was suggested that interstitial diffusion to sinks occurred directly after dissociation. In the case of Te-rich material, this process was thought to be retarded by the re-trapping of Cd vacancies.

S.G.Jahn, Isolde, H.Hofsäss, M.Restle, C.Ronning, H.Quintel, K.Bharuth-Ram, U.Wahl: Journal of Crystal Growth, 1996, 161, 172-6