Term: inhibition
https://doi.org/10.1351/goldbook.I03034

Definition:
The decrease in rate of reaction brought about by the addition of a substance inhibitor), by virtue of its effect on the concentration of a reactant, catalyst or reaction intermediate. For example, molecular oxygen and p-benzoquinone can react as 'inhibitors' in many reactions involving radicals as intermediates by virtue of their ability to act as scavengers toward these radicals. If the rate of a reaction in the absence of inhibitor is v 0 and that in the presence of a certain amount of inhibitor is v, the degree of inhibition (i) is given by: \[i=\frac{v_{0}- v}{v_{0}}\]

Related Terms:
1) mechanism-based inhibition (http://doi.org/10.1351/goldbook.M03805).
2) rate of reaction (http://doi.org/10.1351/goldbook.R05156).
3) inhibitor (http://doi.org/10.1351/goldbook.I03035).
4) catalyst (http://doi.org/10.1351/goldbook.C00876).
5) reaction intermediate (http://doi.org/10.1351/goldbook.R05171).
6) radicals (http://doi.org/10.1351/goldbook.R05066).
7) scavengers (http://doi.org/10.1351/goldbook.S05495).

Source: PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1125 (https://doi.org/10.1351/pac199466051077)

Citation: 'inhibition' 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.I03034

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