Correlation Coefficient and the Isotope Effect for the Diffusion of Zinc in Silver

The correlation factor $f_i$ for the diffusion of zinc in silver has been obtained from measurements of the diffusion of ${\mathrm{Zn}}^{65}$ and ${\mathrm{Zn}}^{69}$ in silver single crystals. $f_i$ increases from 0.47 at 697°C to 0.56 at 952°C. The values of $f_i$ and their temperature dependence agree with those calculated by LeClaire. The self-diffusion coefficients of silver in silver-zinc alloys containing 0 to 4 at.% zinc have been measured at 747 and 880°C. The relative jump frequencies of the zinc atoms and the silver atoms, which are neighbors of the zinc atom, have been calculated from these data, using the theory of Howard and Manning and the results of the isotope-effect experiments. Values of $f_i$ calculated from these data by means of Lidiard's theory are also in agreement with the values obtained from the isotope effect.