作者:Y.M. Zhao、M. Hervieu、N. Nguyen、B. Raveau
DOI:10.1006/jssc.2000.8763
日期:2000.8
transition. A charge disproportionation 2Fe4+↔Fe3++Fe5+ is evidenced by Mössbauer spectroscopy. The electron diffraction study shows the coexistence of orthorhombic and rhombohedral-type domains. A comparison with the other lanthanides (La, Pr, Nd) is also made. This suggests that the size of the Ln3+ ion is not the only parameter which governs the charge ordering in these perovskites, but the oxygen
通过电子衍射显微镜,57 FeMössbauer光谱法首次在钙钛矿Sm 1/3 Sr 2/3 FeO 3− δ中显示了Fe 3+和Fe 5+物种之间的电荷有序(CO)和磁迁移跃迁,并通过测量传输和磁性能。该化合物的电荷有序在T CO = 110 K,这大大低于磁传输跃迁的温度T N = 150K。电荷歧化2Fe 4+ ↔Fe3 + + Fe 5+穆斯堡尔光谱法证明了这一点。电子衍射研究表明,正交和菱面体类型的域共存。还与其他镧系元素(La,Pr,Nd)进行了比较。这表明,Ln 3+离子的大小不是控制这些钙钛矿中电荷顺序的唯一参数,而是影响Fe 5+形成的氧化学计量,也可能在CO现象中起作用。