Term: negative ion
https://doi.org/10.1351/goldbook.N04098

Definition:
An atom, radical, molecule or molecular moiety in the vapour phase which has gained one or more electrons thereby acquiring an electrically negative charge. The use of the term anion as an alternative is not recommended because of its connotations in solution chemistry.

Related Terms:
1) moiety (http://doi.org/10.1351/goldbook.M03968).
2) anion (http://doi.org/10.1351/goldbook.A00358).
3) positive ion (<em>in mass spectrometry</em>) (http://doi.org/10.1351/goldbook.P04768).

Source: Orange Book, 2nd ed., p. 204 (https://media.iupac.org/publications/analytical_compendium/)

Citation: 'negative ion' 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.N04098

License: The IUPAC Gold Book is licensed under Creative Commons Attribution-ShareAlike CC BY-SA 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) for individual terms.

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