Term: isotopomer
https://doi.org/10.1351/goldbook.I03352

Definition:
Isomers having the same number of each isotopic atom but differing in their positions. The term is a contraction of 'isotopic isomer'. Isotopomers can be either constitutional isomers (e.g. CH2DCH=O and CH3CD=O) or isotopic stereoisomers [e.g. (R)- and (S)-CH3CHDOH or (Z)- and (E)-CH3CH=CHD].

Related Terms:
1) isomer (http://doi.org/10.1351/goldbook.I03289).
2) stereoisomers (http://doi.org/10.1351/goldbook.S05984).

Source: PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1132 (https://doi.org/10.1351/pac199466051077)

Citation: 'isotopomer' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.I03352

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