The self-diffusion coefficient of oxygen was determined as a function of temperature in single crystal and polycrystalline samples at up to 1780C. The rate of exchange between a gas phase and solid particles was measured using the stable isotope, 18O. In single crystals, intrinsic diffusion occurred in a high temperature region:

D(cm2/s) = 1.9 x 103 exp[-152000/RT]

Below about 1600C, variable results were obtained; depending upon the impurity content and previous heat treatment. For one set of samples, the experimental results were described by:

D(cm2/s) =6.3 x 10-8 exp[-57600/RT]

Y.Olshi, W.D.Kingery: The Journal of Chemical Physics, 1960, 33[2], 480-6