{"term":{"id":"03011","title":"indirect reaction","longtitle":"IUPAC Gold Book - indirect reaction","doi":"10.1351\/goldbook.I03011","code":"I03011","status":"current","definitions":[{"id":1,"text":"A chemical process in which the reactive complex has a lifetime that is longer than its period of rotation is called an indirect reaction (in contrast to a direct reaction). In a molecular-beam experiment the products of such reactions are scattered at random with reference to the centre of mass of the system. Indirect reactions are also called complex-mode reactions. (They are sometimes called complex reactions, but this usage is not recommended in view of the danger of confusion with composite reactions, which occur in more than one step).","links":[{"term":"complex-mode reactions","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/C01206"},{"term":"composite","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/CT07545"},{"term":"direct reaction","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/D01773"},{"term":"lifetime","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/L03515"},{"term":"molecular-beam","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/M03982"},{"term":"reactive complex","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/R05182"}],"sources":["PAC, 1996, 68, 149. 'A glossary of terms used in chemical kinetics, including reaction dynamics (IUPAC Recommendations 1996)' on page 168 (https:\/\/doi.org\/10.1351\/pac199668010149)"]}],"altoutputs":{"html":"https:\/\/goldbook.iupac.org\/terms\/view\/I03011\/html","xml":"https:\/\/goldbook.iupac.org\/terms\/view\/I03011\/xml","plain":"https:\/\/goldbook.iupac.org\/terms\/view\/I03011\/plain"},"citation":"Citation: 'indirect reaction' 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.I03011","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":"2026-04-20T15:35:03+00:00"}}