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Photochemical process leading to an isomerization of the substrate, either by bond rotation, skeletal rearrangement or atom- or group- transfer.
  1. Typical examples are cis-trans photosomerization of alkenes, polyenes and phototautomerization.
  2. Photochemical pathways have the advantage over thermal and catalytic methods of giving isomer mixtures (photostationary states) rich in thermodynamically unstable isomers.
  3. Photoisomerization is the primary photochemical reaction of the chromophore in several biological photoreceptors such as retinal proteins (e.g., rhodopsin), phytochromes, and the photoactive yellow protein.
PAC, 2007, 79, 293 (Glossary of terms used in photochemistry, 3rd edition (IUPAC Recommendations 2006)) on page 393
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IUPAC. Compendium of Chemical Terminology, 2nd ed. (the "Gold Book"). Compiled by A. D. McNaught and A. Wilkinson. Blackwell Scientific Publications, Oxford (1997). XML on-line corrected version: (2006-) created by M. Nic, J. Jirat, B. Kosata; updates compiled by A. Jenkins. ISBN 0-9678550-9-8.
Last update: 2014-02-24; version: 2.3.3.
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