Term: impact parameter, \(b\)
https://doi.org/10.1351/goldbook.I02987

Definition:
In simple hard sphere collision theory the distance of closest approach that would result for two particles in a collision if the particle trajectories were undeflected by the collision.

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

Source: Green Book, 2nd ed., p. 56 (https://goldbook.iupac.org/files/pdf/green_book_2ed.pdf)

Citation: 'impact parameter, \(b\)' 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.I02987

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