Refinement by atomicity
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Pui Sum Yuen
Abstract
Besides the commonly employed refinement by minimization of the R factor, there is refinement by atomicity. These two refinements lead to two refined structures. Both structures are reasonable and close to each other. The differences between the results of these two refinements are significant. Refinement by atomicity is used as a supplement to refinement by minimization of R factor. For any crystal structure determined by minimization of R factor or other method, with all atoms determined and occupancy of each site equal to 1, in principle, refinement by atomicity should be applied. The purpose is to improve the atomic coordinates. It remains for the X-ray crystallographers to devise a procedure to obtain an improved structure from these two refined structures. The procedure can then be applied to all crystal structures reported in the literatures, or will be published in the future. This means that most articles in X-ray crystallography need to be improved. Many articles and books in other disciplines directly or indirectly contain or use structural informations, such as bond lengths and bond angles, obtained in X-ray crystallography. All these articles and books need to be revised.
Acknowledgments
I thank Dr. R. L. Collin, my Ph.D. supervisor, for his education to me. He taught me X-ray crystallography. This lay the foundation of my research. I thank the Executive Secretary of the IUCr (Mr. M. H. Dacombe) and Miss Carol Cook for the structure factors of beta manganese. I thank the reviewers for very detailed comments, leading to much improvement.
References
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Supplemental Material
The online version of this article (DOI: 10.1515/zkri-2015-1843) offers supplementary material, available to authorized users.
©2015 by De Gruyter
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Articles in the same Issue
- Frontmatter
- Graphical Synopsis
- Inorganic Crystal Structures
- Hydrothermal syntheses and characterization of uranyl tungstates with electro-neutral structural units
- X-ray diffraction investigation on Cu2ZnSiSe4 single and polycrystalline crystals
- Refinement by atomicity
- Organic and Metalorganic Crystal Structures
- Structures of three methoxy-substituted benzaldehyde 7-chloro-1-methyl-4H-quinolinyl-4-ylidene-hydrazones: variations in π···π interactions
- Conformational preferences for isomeric N,N′-bis(pyridin-n-ylmethyl)ethanedithiodiamides, n = 2, 3 and 4: a combined crystallographic and DFT study
- Investigation of the crystal structures of N-(4-fluorobenzoyl)benzenesulfonamide and N-(4-fluoro-benzoyl)-4-methylbenzenesulfonamide
- Hydrogen bonding induced polymorphism in the scandium(III) complex with ε-caprolactam
