Term: principle of least nuclear motion
https://doi.org/10.1351/goldbook.P04849

Definition:
The hypothesis that, for given reactants, the reactions involving the smallest change in nuclear positions will have the lowest energy of activation. (It is also often simply referred to as principle of least motion.)

Related Terms:
1) energy of activation (http://doi.org/10.1351/goldbook.A00102).

Source: PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1134 (https://doi.org/10.1351/pac199466051077)

Citation: 'principle of least nuclear motion' 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.P04849

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