The effects of heat-treatment temperature, THT, and heat-treatment time, tHT, on the structural and magnetic properties of manganites with a nominal composition La0.6Sr0.1MnO3−δ, prepared by the sol–gel method, were investigated. The X-ray diffraction spectra indicated that the samples had two phases, with the R¯3c perovskite being the predominant phase and Mn3O4 being the second phase. It was found that the Curie temperature of the samples varied as THT and tHT were changed. Calculation of the ion content ratios at the A, B, and O sites in the ABO3 perovskite phase on the basis of the thermal equilibrium theory of crystal defects, and Rietveld fitting of X-ray powder diffraction data led to the belief that the origin of this variation was the fact that the vacancy content, z, at B-sites in the ABO3 perovskite phase increased as THT and tHT increased. The calculations also showed that the samples were double-phase compositions of La0.6Sr0.1Mn1−yO1.5(1.7-y+z)/(Mn3O4)y/3.

Influence of Heat Treatment on the Vacancy Content at the B-Site in the ABO3 Manganites La0.6Sr0.1MnO3−δ. S.P.Liu, Y.G.Zhang, G.D.Tang, W.H.Qi, D.H.Ji, Y.F.Li, G.H.Liu, Y.Xie, W.Chen, D.L.Hou: Physica Status Solidi A, 2010, 207[11], 2437–45