123.

Briefly explain the rules for writing down the names of the coordination compounds.

The rules which are to be followed while writing down the names of the coordination compounds are:

(i) The cationic part of the coordination compound is written first followed by the names of the anion with a small gap.

(ii) Within a coordination sphere, ligands names are written in alphabetical order before the name of the central metal atom or ion without leaving any gap.

(iii) To indicate the number of ligands in the coordination sphere two types of prefixes are used:

(a) One are di-, tri-, tetra- etc. These are used when the ligands names are simple.
(b) If the ligands are complex and contain the prefixes like di-, tri-, tetra etc. in their names, then prefixes -bis, -tris, tetrakis etc. are used.


(iv) The names of anionic ligands (both organic and inorganic) ends with –O–. If a ligand name is already having a prefix, its name is enclosed in simple brackets.

Neutral and cationic ligands names are written as such except – water (aqua), NH₃ (–ammine), –CO (–carbonyl) and NO (nitrosyl).

(v) The oxidation state of the central atom or ion is indicated in Roman numerals after the name of the central atom in simple brackets with no gap in between.

(vi) When coordination sphere is an anion then -ate is added to the name of the central metal atom/ion.