Term: mer-
https://doi.org/10.1351/goldbook.M03828

Definition:
An affix used in names to denote meridional; three groups occupying vertices of an octahedral coordination sphere in such a relationship that one is cis to the two others which are themselves trans, not now recommended for precise nomenclature purposes.

Related Terms:
1) coordination (http://doi.org/10.1351/goldbook.C01329).
2) trans (http://doi.org/10.1351/goldbook.C01092).

Source: Red Book, 3rd ed., p. 245 (https://doi.org/10.1515/pac-2014-0718)

Citation: '<i>mer</i>-' 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.M03828

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