Term: atom–molecule complex mechanism
https://doi.org/10.1351/goldbook.A00510

Definition:
A mechanism that sometimes applies to the combination of atoms, but rarely of free radicals. In this mechanism the atom A first combines with a third body or chaperon, A00510-1.png and the complex AM then forms A2 + M by collision with another atom A.Contrast the energy-transfer mechanism.

Related Terms:
1) third body (http://doi.org/10.1351/goldbook.T06361).
2) chaperon (http://doi.org/10.1351/goldbook.C00973).
3) energy-transfer mechanism (<em>in photochemistry</em>) (http://doi.org/10.1351/goldbook.E02116).

Image: Not defined (https://goldbook.iupac.org/img/inline/A00510-1.png) 

Source: PAC, 1996, 68, 149. 'A glossary of terms used in chemical kinetics, including reaction dynamics (IUPAC Recommendations 1996)' on page 153 (https://doi.org/10.1351/pac199668010149)

Citation: 'atom–molecule complex mechanism' 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.A00510

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