The diffusivity, at temperatures of between 200 and 500C, was determined by using a serial sectioning technique (figure 3). A change in the diffusion mechanism of Ni occurred at about 400C. This was tentatively attributed to vacancy generation in a basal Cu-O plane. There were marked differences in the temperature dependences, and these were attributed to the differences in atomic number and atomic radii.

V.N.Alfeev, P.P.Gorbik, V.V.Dyakin, F.A.Zaitov, V.M.Ogenko, G.M.Shalyapina: Solid State Communications, 1991, 77[1], 49-51

Figure 3

Diffusivity of In, Ni and Sn in Cu3Ba2YO7