Title: nth order phase transition
Long Title: IUPAC Gold Book - <i>n</i>th order phase transition
DOI: 10.1351/goldbook.N04224
Status: current

Definition
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.

Related Terms
- Gibbs energy: https://goldbook.iupac.org//terms/view/G02629
- chemical potential: https://goldbook.iupac.org//terms/view/C01032
- first-order phase transition: https://goldbook.iupac.org//terms/view/F02390
- second-order transition: https://goldbook.iupac.org//terms/view/S05531

Source
- 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)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/N04224/html
- json: https://goldbook.iupac.org/terms/view/N04224/json
- xml: https://goldbook.iupac.org/terms/view/N04224/xml

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
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Accessed: 2026-08-09T07:10:15+00:00