It was found that the diffusivity could be as low as 10-12 to 10-11cm2/s at 1000C. Corresponding ionic conductivities of 10-7 to 10-6S/cm were estimated from these diffusion data.

I.Yasuda, K.Ogasawara, M.Hishinuma, T.Kawada, M.Dokiya: Solid State Ionics, 1996, 86-88[2], 1197-201