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Updated: Jul 4, 2025
Microcrystallography of Protein Crystals and In Cellulo Diffraction
Published on: July 21, 2017
Understanding extended homometry based on complementary crystallographic orbit sets
Zeyue Zhang1, Yihan Shen1, Junliang Sun1
1College of Chemistry and Molecular Engineering, Beijing National Laboratory for Molecular Sciences, Peking University, 292 Chengfu Road, Beijing, 100871, People's Republic of China.
Abstract:
Extended homometry is a phenomenon in which distinct structures have the same X-ray diffraction (XRD) intensities, which may lead to incorrect results of structural analysis based on XRD methods. It is proposed and proved herein that half of a crystallographic orbit has the same powder X-ray diffraction intensity as its complementary set; three more theorems are deduced. These results are conducive to understanding the formation of extended homometric structures. Also analyzed are some reported or potential homometric or weakly homometric structures in the Inorganic Crystal Structure Database to confirm the theorems. This work presents a quick approach to analyze and construct extended homometric structures based on crystallographic orbits.
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