Term: onium compounds
https://doi.org/10.1351/goldbook.O04291

Definition:
Cations (with their counter-ions) derived by addition of a hydron to a mononuclear parent hydride of the nitrogen, chalcogen and halogen families. (H4N+) ammonium (H3O+) oxonium (H2F+) fluoronium (H4P+) phosphonium (H3S+) sulfonium (H2Cl+) chloronium (H4As+) arsonium (H3Se+) selenonium (H2Br+) bromonium (H4Sb+) stibonium (H3Te+) telluronium (H2I+) iodonium (H4Bi+) bismuthonium

Related Terms:
1) cations (http://doi.org/10.1351/goldbook.C00907).
2) hydron (<em>in an ion exchanger, in colloid chemistry</em>) (http://doi.org/10.1351/goldbook.H02904).
3) counter-ions (<em>in an ion exchanger, in colloid chemistry</em>) (http://doi.org/10.1351/goldbook.C01371).
4) parent hydride (<em>in an ion exchanger, in colloid chemistry</em>) (http://doi.org/10.1351/goldbook.P04405).

Source: 

Citation: 'onium compounds' 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.O04291

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