Oxygen self-diffusion coefficients, determined experimentally using a variety of techniques, were reviewed and compared. In the case of essentially stoichiometric UO2, the expression,

D(cm2/s) = 1.15 exp[-56700/RT]

fitted the data for three separate sets of observations covering a range of 10 orders of magnitude.

J.Belle: Journal of Nuclear Materials, 1969, 30[1-2], 3-15