Oxley Mark P, Kapetanakis Myron D, Prange Micah P, Varela Maria, Pennycook Stephen J, Pantelides Sokrates T
1Department of Physics and Astronomy,Vanderbilt University,Nashville,Tennessee 37235,USA.
2Materials Science and Technology Division,Oak Ridge National Laboratory,Oak Ridge,Tennessee 37831,USA.
Microsc Microanal. 2014 Jun;20(3):784-97. doi: 10.1017/S1431927614000610. Epub 2014 Mar 31.
We present a theoretical framework for calculating probe-position-dependent electron energy-loss near-edge structure for the scanning transmission electron microscope by combining density functional theory with dynamical scattering theory. We show how simpler approaches to calculating near-edge structure fail to include the fundamental physics needed to understand the evolution of near-edge structure as a function of probe position and investigate the dependence of near-edge structure on probe size. It is within this framework that density functional theory should be presented, in order to ensure that variations of near-edge structure are truly due to local electronic structure and how much from the diffraction and focusing of the electron beam.
我们通过将密度泛函理论与动态散射理论相结合，提出了一种用于计算扫描透射电子显微镜中与探针位置相关的电子能量损失近边结构的理论框架。我们展示了计算近边结构的更简单方法是如何未能包含理解近边结构随探针位置变化所需的基本物理原理的，并研究了近边结构对探针尺寸的依赖性。正是在这个框架内，应该呈现密度泛函理论，以确保近边结构的变化真正是由于局部电子结构，以及有多少是由于电子束的衍射和聚焦。
