Term: degenerate chain branching
https://doi.org/10.1351/goldbook.D01557

Definition:
Sometimes chain branching is brought about by an intermediate which has a long lifetime compared with an ordinary free radical. If this intermediate can break down in different ways, only one of which leads to branching, there may be a relatively slow increase in the number of radicals, and there is said to be degenerate chain branching.

Related Terms:
1) chain branching (http://doi.org/10.1351/goldbook.C00948).
2) lifetime (http://doi.org/10.1351/goldbook.L03515).
3) free radical (http://doi.org/10.1351/goldbook.F02519).

Source: PAC, 1996, 68, 149. 'A glossary of terms used in chemical kinetics, including reaction dynamics (IUPAC Recommendations 1996)' on page 162 (https://doi.org/10.1351/pac199668010149)

Citation: 'degenerate chain branching' 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.D01557

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