Term: fragment ion
https://doi.org/10.1351/goldbook.F02508

Definition:
An electrically charged dissociation product of an ionic fragmentation. Such an ion may dissociate further to form other electrically charged molecular or atomic moieties of successively lower formula weight.

Related Terms:
1) daughter ion (<em>in mass spectrometry</em>) (http://doi.org/10.1351/goldbook.D01524).
2) dissociation (<em>in mass spectrometry</em>) (http://doi.org/10.1351/goldbook.D01801).
3) fragmentation (<em>in mass spectrometry</em>) (http://doi.org/10.1351/goldbook.F02506).
4) weight (<em>in mass spectrometry</em>) (http://doi.org/10.1351/goldbook.W06668).

Source: Orange Book, 2nd ed., p. 205 (https://media.iupac.org/publications/analytical_compendium/)

Citation: 'fragment 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.F02508

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