Naming Ligands

To name a complex ion, every ligand is named first, followed by the central metal atom/ion; when more than one kind of ligand is present, the ligand names are listed in strict alphabetical order (ignoring any multiplying prefix). Anionic ligand names end in the letter 'o' (e.g. chlorido, cyanido) and cationic ligand names end in 'ium', while neutral ligands mostly keep their molecular name, with a handful of memorised exceptions: H₂O is 'aqua', CO is 'carbonyl', NH₃ is 'ammine' and NO is 'nitrosyl'. An ambidentate ligand -- one that can bind through either of two different donor atoms -- carries a κ-term identifying which atom is actually bonded: thiocyanate bound through sulfur is named thiocyanato-κS, while bound through nitrogen it is thiocyanato-κN. When a coordination entity contains more than one ligand of the same kind, the count (2, 3, 4...) is shown with a Greek numerical prefix (di, tri, tetra...) attached to the ligand name; but if the ligand's own name already contains a Greek-derived syllable (as in ethylenediamine), an alternative prefix (bis, tris, …