Term: elementary reaction
https://doi.org/10.1351/goldbook.E02035

Definition:
A reaction for which no reaction intermediates have been detected or need to be postulated in order to describe the chemical reaction on a molecular scale. An elementary reaction is assumed to occur in a single step and to pass through a single transition state.

Related Terms:
1) stepwise reaction (http://doi.org/10.1351/goldbook.S05970).
2) reaction intermediates (http://doi.org/10.1351/goldbook.R05171).
3) transition state (http://doi.org/10.1351/goldbook.T06468).

Source: PAC, 1993, 65, 2291. 'Nomenclature of kinetic methods of analysis (IUPAC Recommendations 1993)' on page 2294 (https://doi.org/10.1351/pac199365102291)

Citation: 'elementary reaction' 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.E02035

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