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.
出处
《电子显微学报》
CAS
CSCD
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)