The impurity tracer diffusion of 59Fe was measured as a function of O activity at 1200C. The results (table 57) could be explained in terms of weak impurity-vacancy binding at high O potentials and of strong binding at low O potentials. Impurity tracer diffusion was also measured in CoO which had been exposed to an O potential gradient. In addition to normal Brownian motion, the impurity cations drifted in the crystal due to a cation vacancy wind.

M.Martin, S.Dorris: Berichte der Bunsengesellschaft für Physikalische Chemie, 1987, 91[8], 779-85

Table 57

Diffusion of 59Fe in CoO as a Function of O Activity at 1200C