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arXiv · 0908.0341

Characteristics of Precession Electron Diffraction Intensities from Dynamical Simulations

W. Sinkler·L. D. Marks
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Abstract

Precession Electron Diffraction (PED) offers a number of advantages for crystal structure analysis and solving unknown structures using electron diffraction. The current article uses many-beam simulations of PED intensities, in combination with model structures, to arrive at a better understanding of how PED differs from standard unprecessed electron diffraction. It is shown that precession reduces the chaotic oscillatory behavior of electron diffraction intensities as a function of thickness. An additional characteristic of PED which is revealed by simulations is reduced sensitivity to structure factor phases. This is shown to be a general feature of dynami-cal intensities collected under conditions in which patterns with multiple incident beam orienta-tions are averaged together. A new and significantly faster method is demonstrated for dynami-cal calculations of PED intensities, based on using information contained in off-central columns of the scattering matrix.

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W. Sinkler, L. D. Marks. 2009-08-03. Characteristics of Precession Electron Diffraction Intensities from Dynamical Simulations. https://doi.org/10.1524/zkri.2010.1199

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