Term: variational transition state theory
https://doi.org/10.1351/goldbook.V06603

Definition:
This expression is applied to modifications of conventional transition state theory in which the position of the dividing surface in the potential-energy surface is varied. The rate is calculated with the surface at various positions, and the lowest rate calculated is taken to be closest to the truth.

Related Terms:
1) transition state theory (http://doi.org/10.1351/goldbook.T06470).
2) dividing surface (http://doi.org/10.1351/goldbook.D01823).

Source: PAC, 1996, 68, 149. 'A glossary of terms used in chemical kinetics, including reaction dynamics (IUPAC Recommendations 1996)' on page 190 (https://doi.org/10.1351/pac199668010149)

Citation: 'variational transition state theory' 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.V06603

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