La_(0.4)FeCo_3Sb_(12)晶体结构的x射线和电子衍射表征  

Characterisation of the crystal structure of La_(0.4)FeCo_3Sb_(12) by means of x-ray and electron diffractions

作　　者：徐敏[1] 沈雯[1] 高瞻[1] 赵良磊[1] 姜蓓[1] 杨磊[1] 张澜庭[1] 

机构地区：[1]上海交通大学材料科学与工程学院

出　　处：《物理学报》2005年第7期3302-3306,共5页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:59902003);上海交通大学"本科生研究计划(PRP)"(批准号:050305)资助的课题.~~

摘　　要：用粉末x射线衍射结合Rietveld解析方法和电子衍射研究了一种n型La0.4FeCo3Sb12化合物的晶体结构和演化.二元Skutterudite化合物的晶体结构中存在一半径为0.1980nm的结构间隙,可以填入稀土类原子,稀土原子填入后主要引起晶格中Sb原子位置的变化,稀土原子相对于其他原子具有较大的热振动参数.化合物的电子衍射花样具有体心立方晶系的消光规律,晶面的衍射强度与粉末x射线衍射的结果完全一致,有序结构引起了个别强衍射斑点.The crystal structure and its evolution of an n-type La-0.4 FeCo3 Sb-12 compound have been characterized by the Rietveld refinement and TEM observation. An interstitial site 0.1980nm in radius has been found in the lattice of the binary Skutterudite compound. Filling this interstitial site by rare earth atom mainly results in a change of lattice coordinates of the Sb atom in the compound. Thermal vibration parameter of the rare earth atom is larger than those of other atoms. The electron diffraction patterns confirm the bcc structure of this compound. The intensities of diffraction from different crystallographic planes correspond well between electron and powder x-ray diffractions.

关 键 词：晶体结构 Skutterudite化合物 X射线 RIETVELD 粉末x射线衍射 表征 电子衍射花样 稀土原子 解析方法 原子位置 立方晶系 振动参数 衍射强度 有序结构 稀土类 填入 晶格 

分 类 号：O76[理学—晶体学]