Title: equilibrium film
Long Title: IUPAC Gold Book - equilibrium film
DOI: 10.1351/goldbook.E02181
Status: current

Definition
A liquid film of thickness, or thicknesses, at which it is stable or metastable with respect to small thickness changes. Unless the area of the film is small, its composition may not be the same over its area and the (metastable) equilibrium thickness may be characteristic of the local condition only.

Related Terms
- film: https://goldbook.iupac.org//terms/view/F02366
- metastable: https://goldbook.iupac.org//terms/view/M03872
- metastable: https://goldbook.iupac.org//terms/view/S05901
- stable: https://goldbook.iupac.org//terms/view/S05900

Source
- PAC, 1972, 31, 577. 'Manual of Symbols and Terminology for Physicochemical Quantities and Units, Appendix II: Definitions, Terminology and Symbols in Colloid and Surface Chemistry' on page 614 (https://doi.org/10.1351/pac197231040577)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/E02181/html
- json: https://goldbook.iupac.org/terms/view/E02181/json
- xml: https://goldbook.iupac.org/terms/view/E02181/xml

Citation: Citation: 'equilibrium film' 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.E02181
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Accessed: 2026-04-08T02:05:09+00:00