Term: line-of-centres model
https://doi.org/10.1351/goldbook.L03563

Definition:
A form of the collision theory of chemical reactions in which the assumption is made that reaction can only occur if on collision the component of energy along the line of centres of the masses of the colliding species is greater than a particular threshold energy.

Related Terms:
1) collision theory (http://doi.org/10.1351/goldbook.C01170).
2) threshold energy (http://doi.org/10.1351/goldbook.T06366).

Source: PAC, 1996, 68, 149. 'A glossary of terms used in chemical kinetics, including reaction dynamics (IUPAC Recommendations 1996)' on page 171 (https://doi.org/10.1351/pac199668010149)

Citation: 'line-of-centres model' 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.L03563

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