Term: reaction barrier
https://doi.org/10.1351/goldbook.R05166

Definition:
The energy barrier to chemical reaction. In vibrationally adiabatic transition-state theory its height is the zero-point energy of the activated complex minus that of the reactants.

Related Terms:
1) adiabatic transition-state theory (http://doi.org/10.1351/goldbook.A00146).
2) activated complex (http://doi.org/10.1351/goldbook.A00092).

Source: PAC, 1996, 68, 149. 'A glossary of terms used in chemical kinetics, including reaction dynamics (IUPAC Recommendations 1996)' on page 183 (https://doi.org/10.1351/pac199668010149)

Citation: 'reaction barrier' 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.R05166

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