Title: isotopically substituted
Long Title: IUPAC Gold Book - isotopically substituted
DOI: 10.1351/goldbook.I03338
Status: current

Definition
Describes a compound that has a composition such that essentially all the molecules of the compound have only the indicated nuclide at each designated position. For all other positions, the absence of nuclide indication means that the nuclide composition is the natural one.

Related Term
- nuclide: https://goldbook.iupac.org/terms/view/N04257

Sources
- Blue Book, p. 514 (https://www.acdlabs.com/iupac/nomenclature/)
- PAC, 1981, 53, 1887. 'Nomenclature of inorganic chemistry: II.1 - Isotopically modified compounds' on page 1890 (https://doi.org/10.1351/pac198153101887)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/I03338/html
- json: https://goldbook.iupac.org/terms/view/I03338/json
- xml: https://goldbook.iupac.org/terms/view/I03338/xml

Citation: Citation: 'isotopically substituted' 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.I03338
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Accessed: 2026-05-15T02:42:57+00:00