Term: group
https://doi.org/10.1351/goldbook.G02705

Definition:
A defined linked collection of atoms or a single atom within a molecular entity. This use of the term in physical organic and general chemistry is less restrictive than the definition adopted for the purpose of nomenclature of organic compounds.

Related Terms:
1) characteristic group (<em>in organic nomenclature</em>) (http://doi.org/10.1351/goldbook.C00976).
2) principal group (<em>in inorganic nomenclature</em>) (<em>in organic nomenclature</em>) (http://doi.org/10.1351/goldbook.P04846).
3) substituent (<em>in organic nomenclature</em>) (http://doi.org/10.1351/goldbook.S06076).
4) collection (<em>in organic nomenclature</em>) (http://doi.org/10.1351/goldbook.C01148).
5) molecular entity (<em>in organic nomenclature</em>) (http://doi.org/10.1351/goldbook.M03986).

Source: PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1118 (https://doi.org/10.1351/pac199466051077)

Citation: 'group' 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.G02705

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