The diffusivity of O was determined by using an electrochemical technique. Under direct-current polarization, the O-ion conductivity was measured and then converted into a diffusion coefficient by using a modified Nernst-Einstein equation. It was found that the data, for temperatures of between 412 and 800C, could be described by:

D (cm2/s) = 0.00498 exp[-0.50(eV)/kT]

I.Kontoulis, B.C.H.Steele: Solid State Ionics, 1991, 47[3-4], 317-24