Free Radicals, Ions, and Radical Ions

Multiply Charged Ions Rule C-85

85.1 - When two or more cationic centres named in Table C-V are present in a single structure, that occurring highest in the Table is designated as suffix and the endings "-onium" of the others are changed to "-onio-" for citation as prefixes. Alternatively replacement nomenclature may be used.

Examples to Rule C-85.1

85.2 - When two or more cationic centres that cannot all be named as in Table C-V are present in a single structure, one of them is chosen as senior and its name, or the name of the component containing it, is used as parent; the other cationic centres are named by use of the prefixes designating either the centres themselves or the components in which they occur. The senior cationic centre is chosen according to the nature of its central atom, with the priorities (a) carbon and (b) then hetero atoms in the order of Table C-V. If a choice remains, then within each type having the same central atom, cyclic structures take precedence over acyclic, and the order of precedence of cyclic structures is that given in Subsection C-0.14.

Examples to Rule C-85.2

See Recommendations'93 R-5.8.4

Two or More Kinds of Ionic Centre with the Same Kind of Charge in a Single Structure
Rule C-86
Positive and Negative Ionic Centres in a Single Structure
Rule C-87


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