Term: collision complex
https://doi.org/10.1351/goldbook.C01160

Definition:
An ensemble formed by two reaction partners for which the distance is the sum of their van der Waals radii. As such it constitutes a subclass of the species indicated as encounter complex.

Related Terms:
1) encounter complex (http://doi.org/10.1351/goldbook.E02087).

Source: PAC, 1996, 68, 2223. 'Glossary of terms used in photochemistry (IUPAC Recommendations 1996)' on page 2233 (https://doi.org/10.1351/pac199668122223)

Citation: 'collision complex' 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.C01160

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