Transition Metal Ion States and Their Interactions of Perovskite-type Mixed Oxides LaMyM'_(1-y)O_3
Liu Shetian; Yu Zuolong; Wu Yue(Changchun Institute of Applied Chemistry of Chinese Academy of Sciences Changchun 130022 China)
The transition metal ion states and their interactions in B-site mired perovskite-type chides LaMyM'1-yO3 (M, M'=Mn, Fe, Co) were discussed. In Mn-Co combined system, the ferromagnetic superexchange interaction of Mn3+-O2--Mn4+ plays a dominant role upon the magnetic property of the Mn-rich samples (y0.5) and the concentrations of Co2+ and Co3+ in CO-rich samples (y0.5) is the main factor influencing their magnetic and electronic properties. The strong ferromagnetic property of the sample with a composition of y=0.5 is mainly due to its crystal structure. In Fe-Mn and Fe-Co systems, the variant Fe ion states are mainly due to the distribution of Mn or Co in its neighboring transition metal ion site and the different redox properties of Mn, Fe, Co ions.