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Updated: Jun 12, 2026

Measurement of X-ray Beam Coherence along Multiple Directions Using 2-D Checkerboard Phase Grating
Published on: October 11, 2016
The symmetry of precession electron diffraction patterns
J-P Morniroli1, P Stadelmann, G Ji
1Laboratoire de Métallurgie Physique et Génie des Matériaux, UMR CNRS 8517, USTL and ENSCL, Cité Scientifique, 59655 Villeneuve d'Ascq, France. Jean-Paul.Morniroli@univ-lille1.fr
Abstract:
The integrated intensity of the diffracted beams present on microdiffraction precession patterns can be used to infer the 'ideal' symmetry, i.e. the symmetry which takes into account both the position and the intensity of the diffracted beams on a diffraction pattern. It is shown that this symmetry is connected with the 11 Laue classes on conventional electron precession patterns and with the centro- and non-centrosymmetrical point groups on unconventional precession patterns obtained without 'descan'.
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