Title: geminate recombination
Long Title: IUPAC Gold Book - geminate recombination
DOI: 10.1351/goldbook.G02603
Status: current

Definition
This expression refers to the reaction, with each other, of two transient species produced from a common precursor in solution. If reaction occurs before any separation by diffusion has occurred, this is termed primary geminate recombination. If the mutually reactive entities have been separated, and come together by diffusion, this is termed secondary geminate recombination. This is illustrated in the reaction diagram below: 

Related Terms
- cage: https://dev.goldbook.iupac.org/terms/view/C00769
- diffusion: https://dev.goldbook.iupac.org/terms/view/D01716
- transient species: https://dev.goldbook.iupac.org/terms/view/T06451

Sources
- PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1117 (https://doi.org/10.1351/pac199466051077)
- PAC, 1996, 68, 149. 'A glossary of terms used in chemical kinetics, including reaction dynamics (IUPAC Recommendations 1996)' on page 166 (https://doi.org/10.1351/pac199668010149)

Other Outputs
- html: https://dev.goldbook.iupac.org/terms/view/G02603/html
- json: https://dev.goldbook.iupac.org/terms/view/G02603/json
- xml: https://dev.goldbook.iupac.org/terms/view/G02603/xml

Citation: Citation: 'geminate recombination' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.G02603
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Accessed: 2026-02-15T10:27:40+00:00