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Electron crystallography is a method to determine the arrangement of atoms in solids using a transmission electron microscope (TEM). It can involve the use of high-resolution transmission electron microscopy images, electron diffraction patterns including convergent-beam electron diffraction or combinations of these. It has been successful in determining some bulk structures, and also surface structures. Two related methods are low-energy electron diffraction which has solved the structure of many surfaces, and reflection high-energy electron diffraction which is used to monitor surfaces often during growth.
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A crystallographic database is a database specifically designed to store information about the structure of molecules and crystals. Crystals are solids having, in all three dimensions of space, a regularly repeating arrangement of atoms, ions, or molecules. They are characterized by symmetry, morphology, and directionally dependent physical properties. A crystal structure describes the arrangement of atoms, ions, or molecules in a crystal.
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Crystallographic image processing (CIP) is traditionally understood as being a set of key steps in the determination of the atomic structure of crystalline matter from high-resolution electron microscopy (HREM) images obtained in a transmission electron microscope (TEM) that is run in the parallel illumination mode. The term was created in the research group of Sven Hovmöller at Stockholm University during the early 1980s and became rapidly a label for the "3D crystal structure from 2D transmission/projection images" approach. Since the late 1990s, analogous and complementary image processing techniques that are directed towards the achieving of goals with are either complementary or entirely beyond the scope of the original inception of CIP have been developed independently by members of the computational symmetry/geometry, scanning transmission electron microscopy, scanning probe microscopy communities, and applied crystallography communities.
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Precession electron diffraction (PED) is a specialized method to collect electron diffraction patterns in a transmission electron microscope (TEM). By rotating (precessing) a tilted incident electron beam around the central axis of the microscope, a PED pattern is formed by integration over a collection of diffraction conditions. This produces a quasi-kinematical diffraction pattern that is more suitable as input into direct methods algorithms to determine the crystal structure of the sample.
Structural chemistry is a part of chemistry and deals with spatial structures of molecules and solids. For structure elucidation a range of different methods is used. One has to distinguish between methods that elucidate solely the connectivity between atoms (constitution) and such that provide precise three dimensional information such as atom coordinates, bond lengths and angles and torsional angles.
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Steven L. Suib is an American inorganic chemist, academic and researcher. He is a Board of Trustees Distinguished Professor of Chemistry at University of Connecticut. He is a director of the Institute of Materials Science and of the Center for Advanced Microscopy and Materials Analysis.
Kenneth J. Balkus Jr. is an American chemist and materials scientist. He is professor of chemistry and former department chair at The University of Texas at Dallas. He is a Fellow of the American Chemical Society and a recipient of the ACS Doherty Award. His well known work is synthesis of zeolite UTD-1, the first high-silica zeolite to contain a one-dimensional, extra-large 14-ring pore system. Other notable work include rare-earth metal organic frameworks. He is editor to Journal of Porous Materials, Springer. He is also co-founder of DB Therapeutics, a company developing cancer therapies.
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References
- 1 2 3 "Xiaodong Zou, Stockholm University". foundry.lbl.gov. Retrieved 2022-03-10.
- 1 2 "Revolutionary close-ups of the building blocks of life | Knut and Alice Wallenberg Foundation". kaw.wallenberg.org. Retrieved 2022-03-10.
- ↑ "Xiaodong Zou's Group - Department of Materials and Environmental Chemistry". www.mmk.su.se. Retrieved 2022-03-10.
- ↑ Zou, Xiaodong (2006). "What is Electron Crystallography?". In Weirich, Thomas E.; Lábár, János L.; Zou, Xiaodong (eds.). Electron Crystallography. NATO Science Series II: Mathematics, Physics and Chemistry. Vol. 211. Dordrecht: Springer Netherlands. pp. 3–16. Bibcode:2006ecna.book....3Z. doi:10.1007/1-4020-3920-4_1. ISBN 978-1-4020-3920-1.
- ↑ "Xiaodong Zou answers questions about 15 years of research on covalent organic frameworks". Nature Communications. 11 (1): 5330. 2020-11-16. Bibcode:2020NatCo..11.5330.. doi: 10.1038/s41467-020-19300-z . ISSN 2041-1723. PMC 7669865 . PMID 33199686. S2CID 226984929.
- ↑ Zou, Xiaodong; Hovmöller, Sven; Oleynikov, Peter (2011). Electron Crystallography: Electron Microscopy and Electron Diffraction. International Union of Crystallography Texts on Crystallography. Oxford: Oxford University Press. doi:10.1093/acprof:oso/9780199580200.001.0001. ISBN 978-0-19-958020-0.
- ↑ "Materials, Characterization, and Applications". www.exselent.su.se. Retrieved 2022-03-10.
- 1 2 "K.H. Kuo Fund". med.nyu.edu. Retrieved 2022-03-10.
- ↑ "Göran Gustafsson Prize - Stockholm University". www.su.se. Retrieved 2022-03-10.
- ↑ "Pernilla Wittung-Stafshede awarded medal for her research | Chalmers". www.chalmers.se. Retrieved 2022-03-10.
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