Term: geminate recombination
https://doi.org/10.1351/goldbook.G02603

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: G02603.png

Related Terms:
1) cage (http://doi.org/10.1351/goldbook.C00769).
2) transient species (http://doi.org/10.1351/goldbook.T06451).
3) diffusion (http://doi.org/10.1351/goldbook.D01716).

Image: Not defined (https://goldbook.iupac.org/img/inline/G02603.png) 

Source: PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1117 (https://doi.org/10.1351/pac199466051077)

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. https://doi.org/10.1351/goldbook.G02603

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