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arXiv · 1811.00089

Structure refinement from 'Digital' Large Angle Convergent Beam Electron Diffraction Patterns

Alex Hubert·Rudolf A. Römer·Richard Beanland
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Abstract

We use semi-automated data acquisition and processing to produce digital large angle CBED (D-LACBED) patterns. We demonstrate refinements of atomic coordinates and isotropic Debye-Waller factors for well-known materials using simulations produced with a neutral, spherical independent atom model. We find that atomic coordinate refinements in Al2O3 have sub-pm precision and accuracy. Isotropic DWFs are accurate for Cu, a simple fcc metal, but do not agree with X-ray measurements of GaAs or Al2O3. This indicates that models of bonding will be essential to fully interpret D-LACBED data.

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Alex Hubert, Rudolf A. Römer, Richard Beanland. 2018-10-16. Structure refinement from 'Digital' Large Angle Convergent Beam Electron Diffraction Patterns. https://doi.org/10.1016/j.ultramic.2018.12.007

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