{"term":{"id":"04224","title":"<i>n<\/i>th order phase transition","longtitle":"IUPAC Gold Book - <i>n<\/i>th order phase transition","doi":"10.1351\/goldbook.N04224","code":"N04224","status":"current","definitions":[{"id":1,"text":"A transition in which the molar Gibbs energy (or chemical potential) and its \\((n - 1)\\)th-order derivatives are continuous, whereas the \\(n\\)th-order derivatives with respect to temperature and pressure are discontinuous at the transition point.","links":[{"term":"Gibbs energy","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/G02629"},{"term":"chemical potential","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/C01032"},{"term":"first-order phase transition","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/F02390"},{"term":"second-order transition","url":"https:\/\/goldbook.iupac.org\/\/terms\/view\/S05531"}],"sources":["PAC, 1994, 66, 577. 'Definitions of terms relating to phase transitions of the solid state (IUPAC Recommendations 1994)' on page 587 (https:\/\/doi.org\/10.1351\/pac199466030577)"]}],"altoutputs":{"html":"https:\/\/goldbook.iupac.org\/terms\/view\/N04224\/html","xml":"https:\/\/goldbook.iupac.org\/terms\/view\/N04224\/xml","plain":"https:\/\/goldbook.iupac.org\/terms\/view\/N04224\/plain"},"citation":"Citation: '<i>n<\/i>th order phase transition' 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.N04224","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":"2026-08-09T07:10:20+00:00"}}