Term: resonance hybrid
https://doi.org/10.1351/goldbook.RT07094

Definition:
A localized valence bond representation of a molecule. This describes pictorially an electronic wavefunction that makes some contribution to the state wavefunction of the system. resonance hybrids are needed to describe the state of a system when that system is not adequately described by a single Lewis structure.

Related Terms:
1) valence (http://doi.org/10.1351/goldbook.V06588).
2) resonance (http://doi.org/10.1351/goldbook.R05326).

Source: PAC, 1999, 71, 1919. 'Glossary of terms used in theoretical organic chemistry' on page 1961 (https://doi.org/10.1351/pac199971101919)

Citation: 'resonance hybrid' 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.RT07094

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