The diffusivity of O (table 157), and the migration energy of O ions (table 158), were deduced from the creep response which followed a sudden increase in temperature. It was concluded that a change in O vacancy concentration was directly linked to the diffusion of Ni vacancies to, or from, the surface.

M.Jiménez-Melendo, A.Dominguez-Rodriguez, J.Castaing: Journal of the Physics and Chemistry of Solids, 1991, 52[3], 517-21