It was noted that the diffusion of these solutes could be completely described in terms of interstitial-substitutional exchange mechanisms (dissociative, kick-out). The Zn profiles, after diffusion at temperatures of between 870 and 1208C, were analyzed in order to obtain information concerning the equilibrium concentrations of the intrinsic point defects which were involved in diffusion. An analysis of Zn diffusion data yielded the fractions of Zn atoms which were located on interstitial or substitutional sites, and the mass-action constants of the underlying diffusion-reaction processes. The enthalpy difference between interstitial and substitutional Zn, and the reaction enthalpies for diffusion processes, were deduced from the temperature dependences of these quantities. Total-energy calculations for Zn, Pt and Au on substitutional and tetrahedral interstitial sites were also carried out.

H.Bracht, H.Overhof: Physica Status Solidi A, 1996, 158[1], 47-55