Iupac names of complex compounds Co(SCN) 4 2-, for example, is the tetrathiocyanatocobaltate(II) ion. [Ag(NH 3) 2] + diamminesilver(I) [Ni(CO) 4] 0 tetracarbonylnickel(0) 7- For complex compounds which are composed of complex cation and complex anion, the cation is named first then followed by the anion name. The usage of multiple prefixes along with the ordering of components and the usage of the more electronegative component towards the end of the name must be kept in mind while naming these compounds via IUPAC norms. Remember: Name the (possibly complex) cation BEFORE the (possibly complex) anion. Such compounds are referred to as coordination compounds or complex compounds. Example of coordination complexes and compounds are: A ligand can be an anion or a neutral molecule that donates an electron pair to the complex (NH3 NH 3, H2O H 2 O, Cl− Cl −). in a very shell, the principles are as follows: In Coordination Compounds, Within the coordination entities, we tend to list down the central atom/ion 1st followed by the ligands. Multiple functional group rule. These rules are: 1. There are several extant systems of nomenclature and many trivial names are still in use.