立方尖晶石Li(Fe_(0.1)Mn_(1.9))O_4电子结构的穆斯堡尔谱研究  

Electronic Structure of Cubic Li(Fe_(0.1)Mn_(1.9))O_4 Studied with Mssbauer Spectroscopy

作　　者：严立云[1] 

机构地区：[1]吉林师范大学物理学院,吉林四平136000

出　　处：《衡水学院学报》2009年第4期48-50,共3页Journal of Hengshui University

摘　　要：通过对Fe掺杂的尖晶石材料Li(Fe0.1Mn1.9)O4的穆斯堡尔谱研究,得出了不同温度下的同质异能移(IS)和四极劈裂(QS).由同质异能移可知Fe在八面体中处于三价高自旋态,低温时样品的离子性较强.根据晶体场理论,得出能隙随QS而增大,表明Jahn-Teller畸变增大,说明低温下Mn3d电子去局域化,使化合物离子性增强,与IS所得结论一致.The MOssbauer spectra of Fe3＋ doped cubic spinel LiMn2O4 （LiFe0.1Mn1.9O4） in differem temperatures （295K and 80K） are collected by using 57Fe as the radiation source. The values of isomer shift （IS） shows that Fe ion is in a high spin trivalent state in octahedron site and the ionicity of LiFe0.1Mnl.904 increases in 80K compared with that in 295K. Based on the crystal-field theory, the energy gaps between different d orbitals, AE（blg - alg） and 2~E（bEg - eg）, can be estimated from QS. From the different energy gaps we can see that the Jahn-Teller distortion increased and the [MnO6] octahedron enlongated in low temperature. This corresponds to the conclusion deduced from the values of the isomer shift.

关 键 词：Li(Fe0.1Mn1.9)O4 同质异能移 四极分裂 JAHN-TELLER畸变 

分 类 号：TM912[电气工程—电力电子与电力传动]