Term: quencher
https://doi.org/10.1351/goldbook.Q05006

Definition:
A molecular entity that deactivates (quenches) an excited state of another molecular entity, either by energy transfer, electron transfer, or by a chemical mechanism.

Related Terms:
1) excited state (http://doi.org/10.1351/goldbook.E02257).
2) electron transfer (http://doi.org/10.1351/goldbook.E02011).
3) quenching (http://doi.org/10.1351/goldbook.Q05007).
4) stern–volmer kinetic relationships (http://doi.org/10.1351/goldbook.S06004).

Source: PAC, 1996, 68, 2223. 'Glossary of terms used in photochemistry (IUPAC Recommendations 1996)' on page 2268 (https://doi.org/10.1351/pac199668122223)

Citation: 'quencher' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.Q05006

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