Diffusion in Cubic Sulphates

Abstract

The diffusion coefficients of the divalent ions Mg, Zn, Ca, Cd and Pb have been measured between 600 and 800°C. The results can be described by an Arrhenius equation, where the preexponential factors decreases when the radius of the diffusing ion increases. By comparing results for univalent and divalent ions we have found that the formation energy is constant and that the migration energy decreases when the cation radius increases.