定量会聚束电子衍射:Ⅱ.QCBED在镧钙锰氧中的应用  

Quantitative convergent-beam electron diffraction:Ⅱ.Application in La_(2/3)Ca_(1/3)MnO_3

作　　者：冯方[1] 张爱华[1] 朱静[1] 

机构地区：[1]清华大学材料科学与工程系,北京100084

出　　处：《电子显微学报》2007年第2期97-102,共6页Journal of Chinese Electron Microscopy Society

基　　金：国家973计划项目(No.2002CB613505)

摘　　要：本文介绍了定量会聚束电子衍射术在镧钙锰氧材料中的应用。结合La2/3Ca1/3MnO3材料的特点,作者对定量会聚束电子衍射的实验方法和优化程序进行了改进,包括采用图像畸变校正、多起点聚簇全局优化算法等。在对该材料的晶格畸变研究工作的基础上,通过对电子零损失峰能量过滤的会聚束电子衍射图样的拟合测定了La2/3Ca1/3MnO3九个衍射的精细结构因子。Quantitative convergent-beam electron diffraction method （QCBED） was applied to study the complex oxide,La2/3 Ca1/3MnO3 . For this purpose, some modifications, including the consideration of symmetry operation, the image distortion correction and multi-start clustering global optimization algorithm, to the QCBED experiments and optimization program were explored according to the structure feature of La2/3 Ca1/3MnO3. The way to refine atomic position parameters and temperature factors （Debye-Waller factors） without an energy-filter is attempted with the diffraction intensity of high-order Lane zone. Based on these refined atomic position parameters and temperature factors, the nine structure factors of the low-index diffractions were refined by fitting the energy-filtered diffraction patterns with the improved QCBED method.

关 键 词：定量会聚柬电子衍射 结构因子 全局优化算法 LA2/3CA1/3MNO3 

分 类 号：TB383.1[一般工业技术—材料科学与工程]