Thermogravimetric measurements were made, of the deviations in stoichiometry of (Co,Fe,Mn)3-dO4 at 1200C, as a function of the O activity and cationic composition. The observed dependence upon O activity suggested that cation vacancies and cation interstitials were the main defects. Cation tracer (60Co, 59Fe, 54Mn) diffusion data (tables 38 to 40) revealed the existence of minima as a function of the O activity. This showed that cation vacancies and cation interstitials contributed to the cation tracer diffusivity.

F.H.Lu, R.Dieckmann: Solid State Ionics, 1992, 53-56, 290-302