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.
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: http://goldbook.iupac.org (2006-) created by M. Nic, J. Jirat, B. Kosata; updates compiled by A. Jenkins. ISBN 0-9678550-9-8. doi:10.1351/goldbook