Cation Self‐Diffusion in Cr 2 O 3

Self‐diffusion of 51 Cr was measured both parallel to and perpendicular to the c axis in single crystals of Cr 2 O 3 as a function of oxygen partial pressure at 1490° and 1570°C. The oxygen‐partial‐pressure dependence of the diffusivity indicates that cation self‐diffusion occurs by a vacancy mechanism. The values of the self diffusion coefficients determined in this experiment are about 10 4 times smaller than those previously reported in this temperature range .