Term: vibrational relaxation
https://doi.org/10.1351/goldbook.V06615

Definition:
The loss of vibrational excitation energy by a molecular entity through energy transfer to the environment caused by collisions. The molecular entity relaxes into vibrational equilibrium with its environment.

Related Terms:
1) excitation energy (http://doi.org/10.1351/goldbook.E02250).
2) relaxation (http://doi.org/10.1351/goldbook.R05285).

Source: PAC, 1996, 68, 2223. 'Glossary of terms used in photochemistry (IUPAC Recommendations 1996)' on page 2283 (https://doi.org/10.1351/pac199668122223)

Citation: 'vibrational relaxation' 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.V06615

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