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Updated: Jul 25, 2026

X-ray Powder Diffraction in Conservation Science: Towards Routine Crystal Structure Determination of Corrosion Products on Heritage Art Objects
Published on: June 8, 2016
X-ray analysis of Co-C bond cleavage in the crystalline state
1Laboratory of Chemistry for Natural Products, Tokyo Institute of Technology, Japan.
Abstract:
During serial structure analysis of cobaloxime derivatives, aimed at interpreting the catalytic capability of the asymmetric hydrogenation, we have found that the crystal of R-alpha-cyanoethyl (S-alpha-methylbenzylamine)-cobaloxime changes its unit cell dimensions by X-ray exposure without degradation of a single crystal form. The rate of the change was so slow that it was possible to collect the intensity data for several intermediate stages. We have proved, by calculating electron density in each stage, that the change reflects the racemisation of the cyanoethyl group.
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