Interdiffusion in the System CaF ₂ ‐SrF ₂

Abstract

Interdiffusion coefficients were determined in single‐crystal (Ca,Sr)F 2 solid solutions in the temperature range 1100° to 1320°C. The composition dependence of the coefficients passes through a maximum that shifts toward higher CaF 2 concentrations at higher temperatures. Extrapolation of the interdiffusion coefficient to extremes of composition provides impurity diffusion coefficients that agree well with tracer results. The changes in activation energy with composition can be explained readily on the basis of cationic radii and lattice parameters.