{"term":{"id":"03096","title":"intermediate","longtitle":"IUPAC Gold Book - intermediate","doi":"10.1351\/goldbook.I03096","code":"I03096","status":"current","synonym":"<em>synonym<\/em>: reaction intermediate","definitions":[{"id":1,"text":"A molecular entity with a lifetime appreciably longer than a molecular vibration (corresponding to a local potential energy minimum of depth greater than \\(R\\ T\\)) that is formed (directly or indirectly) from the reactants and reacts further to give (either directly or indirectly) the products of a chemical reaction; also the corresponding chemical species.","links":[{"term":"chemical reaction","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/C01033"},{"term":"chemical species","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/CT01038"},{"term":"elementary reaction","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/E02035"},{"term":"lifetime","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/L03515"},{"term":"molecular entity","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/M03986"},{"term":"reaction step","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/R05178"},{"term":"stepwise reaction","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/S05970"}],"sources":["PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1126 (https:\/\/doi.org\/10.1351\/pac199466051077)"],"seealso":["PAC, 1996, 68, 149. 'A glossary of terms used in chemical kinetics, including reaction dynamics (IUPAC Recommendations 1996)' on page 170 (https:\/\/doi.org\/10.1351\/pac199668010149)"]}],"altoutputs":{"html":"https:\/\/goldbook.iupac.org\/terms\/view\/I03096\/html","xml":"https:\/\/goldbook.iupac.org\/terms\/view\/I03096\/xml","plain":"https:\/\/goldbook.iupac.org\/terms\/view\/I03096\/plain"},"citation":"Citation: 'intermediate' 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.I03096","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":"2026-05-31T01:48:18+00:00"}}