Title: energized species
Long Title: IUPAC Gold Book - energized species
DOI: 10.1351/goldbook.E02100
Status: current

Definition
In an elementary process, a species having sufficient energy to become an activated complex, but which does not have the structure of the activated complex. If it is not inactivated by collisions it can become an activated complex and pass at once into products, after undergoing vibration.

Related Term
- activated complex: https://goldbook.iupac.org//terms/view/A00092

Source
- PAC, 1996, 68, 149. 'A glossary of terms used in chemical kinetics, including reaction dynamics (IUPAC Recommendations 1996)' on page 164 (https://doi.org/10.1351/pac199668010149)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/E02100/html
- json: https://goldbook.iupac.org/terms/view/E02100/json
- xml: https://goldbook.iupac.org/terms/view/E02100/xml

Citation: Citation: 'energized species' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.E02100
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Accessed: 2026-04-23T22:13:51+00:00