Term: harpoon mechanism
https://doi.org/10.1351/goldbook.H02746

Definition:
Reaction sequence (thermal or photoinduced) between neutral molecular or atomic entities in which long-range electron transfer is followed by a considerable reduction of the distance between donor and acceptor sites as a result of the electrostatic attraction in the ion pair created.

Related Terms:
1) sequence (http://doi.org/10.1351/goldbook.ST06775).
2) electron transfer (http://doi.org/10.1351/goldbook.E02011).
3) ion pair (http://doi.org/10.1351/goldbook.I03231).

Source: PAC, 1996, 68, 2223. 'Glossary of terms used in photochemistry (IUPAC Recommendations 1996)' on page 2245 (https://doi.org/10.1351/pac199668122223)

Citation: 'harpoon 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.H02746

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