The diffusion of Ce was measured by using tracer and serial sectioning techniques. It was found that the diffusivity obeyed:

D (cm2/s) = 1.1 x 10-3 exp[-0.62(eV)/kT]

It was suggested that the Ce atoms entered the lattice as 3+ ions at substitutional sites, and diffused as an associated complex with cation vacancies.

A.L.Laskar, K.V.Reddy, G.A.Popson: Solid State Ionics, 1988, 28-30, 294-7