{"term":{"id":"02538","title":"Frumkin effect","longtitle":"IUPAC Gold Book - Frumkin effect","doi":"10.1351\/goldbook.F02538","code":"F02538","status":"current","also defines":"<em>also defines<\/em>: 'true' rate constant","definitions":[{"id":1,"text":"In an electrode reaction, when reactants or intermediates are adsorbed, the rate of reaction may no longer be related to the concentration by a simple law. The deviation may be due to either entropic or energetic effects or both. The situation best understood is that where a reactant is non-specifically adsorbed in the outer Helmholtz plane (inner boundary of the diffuse layer). The effect of such adsorption on electrode kinetics is usually termed the Frumkin effect. Rate constants, transfer coefficients etc. corrected for this effect are frequently called 'true' rate constants etc. It would be preferable to describe them as 'corrected for the Frumkin effect', but in any case, if such a correction is carried out, the basis on which it is made should be clearly described.","links":[{"term":"Rate constants","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/O04322"},{"term":"adsorption","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/A00155"},{"term":"concentration","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/C01222"},{"term":"deviation","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/D01650"},{"term":"diffuse layer","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/D01714"},{"term":"electrode reaction","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/E01960"},{"term":"intermediates","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/I03096"},{"term":"rate of reaction","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/R05156"}],"sources":["PAC, 1980, 52, 233. 'Electrode Reaction Orders, Transfer Coefficients and Rate Constants. Amplification of Definitions and Recommendations for Publication of Parameters' on page 239 (https:\/\/doi.org\/10.1351\/pac198052010233)"]}],"altoutputs":{"html":"https:\/\/goldbook.iupac.org\/terms\/view\/F02538\/html","xml":"https:\/\/goldbook.iupac.org\/terms\/view\/F02538\/xml","plain":"https:\/\/goldbook.iupac.org\/terms\/view\/F02538\/plain"},"citation":"Citation: 'Frumkin effect' 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.F02538","license":"The IUPAC Gold Book is licensed under Creative Commons Attribution-ShareAlike CC BY-SA 4.0 International (https:\/\/creativecommons.org\/licenses\/by-sa\/4.0\/) for individual terms.","collection":"If you are interested in licensing the Gold Book for commercial use, please contact the IUPAC Executive Director at executivedirector@iupac.org .","disclaimer":"The International Union of Pure and Applied Chemistry (IUPAC) is continuously reviewing and, where needed, updating terms in the Compendium of Chemical Terminology (the IUPAC Gold Book). Users of these terms are encouraged to include the version of a term with its use and to check regularly for updates to term definitions that you are using.","accessed":"2026-05-11T19:10:53+00:00"}}