Tracer diffusion of O was studied in cation stoichiometric, LaMnO3, and A-site deficient, La0.9MnO3, specimens by means of the isotope-exchange depth-profiling technique; using secondary ion mass spectrometry. The measured O tracer diffusion coefficients ranged from 10-12 to 10-15cm2/s. These values were comparable to those found for Sr-doped lanthanum manganites. The activation energy for O tracer diffusion was 240kJ/mol in LaMnO3, and 294kJ/mol in La0.9MnO3. An A-site deficiency of up to 10% did not affect O tracer diffusion in the lanthanum manganites. Evidence was found for rapid diffusion in the A-site deficient material. This was attributed to grain boundary diffusion.

Oxygen Tracer Diffusion in Undoped Lanthanum Manganites. A.V.Berenov, J.L.MacManus-Driscoll, J.A.Kilner: Solid State Ionics, 1999, 122[1-4], 41-9