Oxygen diffusion coefficients were determined for near-stoichiometric α-Nb2O5 at 850 to 1200C under oxygen pressures of 10-2 to 1atm. At a given temperature, the diffusion coefficient was proportional to pO2-1/4. The temperature

dependence of the diffusion coefficient at a constant oxygen pressure was described by:

D(cm2/s) = 1.72 x 10-2exp[-49.4(kcal/mol)/RT]

W.K.Chen, R.A.Jackson: The Journal of Chemical Physics, 1967, 47[3], 1144-8