{"term":{"id":"05007","title":"quenching","longtitle":"IUPAC Gold Book - quenching","doi":"10.1351\/goldbook.Q05007","code":"Q05007","status":"current","also defines":"<em>also defines<\/em>: dynamic quenching, static quenching","definitions":[{"id":1,"text":"Deactivation of an excited molecular entity intermolecularly by an external environmental influence (such as a quencher) or intramolecularly by a substituent through a non-radiative process.","notes":{"1":"When the external environmental influence (quencher) interferes with the behaviour of the excited state after its formation, the process is referred to as dynamic quenching. Common mechanisms include energy transfer, electron transfer, etc.","2":"When the environmental influence inhibits the excited state formation the process is referred to as static quenching."},"links":[{"term":"Deactivation","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/D01528"},{"term":"electron transfer","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/E02011"},{"term":"excited state","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/E02257"},{"term":"quencher","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/Q05006"}],"sources":["PAC, 2007, 79, 293. 'Glossary of terms used in photochemistry, 3rd edition (IUPAC Recommendations 2006)' on page 407 (https:\/\/doi.org\/10.1351\/pac200779030293)"]}],"altoutputs":{"html":"https:\/\/goldbook.iupac.org\/terms\/view\/Q05007\/html","xml":"https:\/\/goldbook.iupac.org\/terms\/view\/Q05007\/xml","plain":"https:\/\/goldbook.iupac.org\/terms\/view\/Q05007\/plain"},"citation":"Citation: 'quenching' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351\/goldbook.Q05007","license":"The IUPAC Gold Book is licensed under Creative Commons Attribution-ShareAlike CC BY-SA 4.0 International (https:\/\/creativecommons.org\/licenses\/by-sa\/4.0\/) for individual terms.","collection":"If you are interested in licensing the Gold Book for commercial use, please contact the IUPAC Executive Director at executivedirector@iupac.org .","disclaimer":"The International Union of Pure and Applied Chemistry (IUPAC) is continuously reviewing and, where needed, updating terms in the Compendium of Chemical Terminology (the IUPAC Gold Book). Users of these terms are encouraged to include the version of a term with its use and to check regularly for updates to term definitions that you are using.","accessed":"2026-05-09T08:29:29+00:00"}}