Term: resonance effect
https://doi.org/10.1351/goldbook.08204

Definition:
Experimentally observable influence (on reactivity, etc.) of a substituent through electron delocalization to or from the substituent.

Source: PAC, 2022, 94, 353. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 2021)' on page 499 (https://doi.org/10.1515/pac-2018-1010)

Citation: 'resonance effect' 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.08204

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.

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