Exceptions: Names of the type benzenediazonium (Rule C-931), uronium (Rule C-973), and thiouronium (Rule C-974) are used as laid down in the Rules cited.
Examples to Rule C-82.1
Tetramethylammonium Dimethyloxonium Diphenyliodonium Ethylenebromonium
82.2 - If the positive charge of an organic cation is derived by fixation of a proton on a hetero atom of a parent compound whose name does not end in amine, the name of the ion is formed by adding "-ium" to the name of the organic parent compound, with elision of a terminal "e" (if present). When there is more than one hetero atom able to fix the proton, the point of attachment of the proton may be shown by the "indicated hydrogen" method.
82.3 - When replacement ("a") nomenclature is used (see Rule B-6) the ending "-a" of an affix oxa, thia, aza, etc., is changed to "-onia".
Examples to Rule C-82.2
Anilinium Guanidinium 2-Phenylhydrazinium 1-Methylhydrazinium
(for numbering see Rule C-921.5)
Acetonium 1,4-Dioxanium 1-Methylpyridinium Imidazolium Glycinium Prolinium 1,4-Dithian-2-iminium 9aH-Quinolizinium
82.4 - An organic cation formed by addition of a proton to an unsaturated hydrocarbon is named by adding "-ium" to the name of the hydrocarbon, with elision of terminal "e" if present. If desired the point of attachment of the proton is shown by the "indicated hydrogen" method. If a -complex is to be specified, the prefix is used. If the position of the charge is to be specified, the appropriate locant is placed before the ending "-ium".
Example to Rule C-82.3
See Recommendations'93 R-5.8.2
Examples to Rule C-82.4
Ethenium Benzenium Allenium
(position of unknown)
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