Parent ion

This term is not recommended: see precursor ion.

An electrically charged molecular moiety which may dissociate to form fragments, oneor more of which may be electrically charged, and one or more neutral species. Aparent ion may be a molecular ion or an electrically charged fragment of a molecular ion. Synonymous with Precursor ion.

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An electrically charged molecular moiety which may dissociate to form fragments, one or more of which may be electrically charged, and one or more neutral species. A parent ion may be a molecular ion or an electrically charged fragment of a molecular ion.

Source:

PAC, 1991, 63, 1541 (Recommendations for nomenclature and symbolism for mass spectroscopy (including an appendix of terms used in vacuum technology). (Recommendations 1991)) on page 1549

Orange Book, p. 205

Any ion (including negatively and doubly charged ions) that gives fragments.

Any ion that fragments to a product ion.