在定量电子显微镜中用于现象学吸收的精细的三参数方程 - - 确定方程.
Philip N H Nakashima1, Tianyu Liu2, Andrew E Smith3
1Department of Materials Science and Engineering Monash University Victoria3800 Australia.
概括
一个新的三项方程模拟了传输电子显微镜模拟材料中的电子束吸收. 这个方程准确地重现了散射因子,并且可以适应先进的定量融合束电子衍射分析.
科学领域:
- 材料科学 材料科学 材料科学
- 物理 物理学 物理
- 晶体学 晶体学是指结晶学.
背景情况:
- 定量融合束电子衍射 (QCBED) 模拟需要精确的电子散射模型.
- 现有的模型,如ATOM子程序,是有效的,但可能需要对未过的衍射模式进行改进.
研究的目的:
- 为了获得一种新的三项现象学方程,用于材料中电子束的吸收.
- 提高传输电子显微镜 (TEM) 模拟的准确性,特别是对于差异QCBED.
主要方法:
- 开发了一个现象学吸收的三项方程.
- 在广泛的元素和参数中对ATOM子程序的不弹性散射因子验证了方程.
- 研究了局部和非局部散射贡献方程系数的精细化.
主要成果:
- 导出方程准确地复制了ATOM子程序生成的不弹性散射因子 (在几百分之内).
- 该方程适用于元素Z=1-98,德拜-沃勒参数 (0.05-2.0 Å2),散射角度 (0-6.0 Å-1),以及电子能量 (1 keV-1 MeV).
- 方程的系数可以改进,以提高在未过的微分QCBED模式匹配中的适用性.
结论:
- 新的三项方程为材料中电子束吸收提供了一个强大的和可适应的模型.
- 该模型增强了定量TEM模拟的功能,特别是用于未过的QCBED分析.
- 精细的系数在模拟分散现象时提供了更大的灵活性,用于先进材料的表征.
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