Question

What is an ambidentate ligand?

Answer 1

An ambidentate ligand has two or more donor atoms, but when a complex is formed, only one donor atom is attached to the metal.

For example, in $N{O}_2^{-}$ ligand, out of two donor atoms (N and O), only one donor atom is attached to metal as $M-N{O}_2$ or $M-ONO$.

Other examples of ambidentate ligands are ligands $C{N}^{-}$ and $SC{N}^{-}$.

In $C{N}^{-}$ ligand, out of two donor atoms (N and C), only one donor atom is attached to metal as $M-CN$ or $M-NC$.

In $SC{N}^{-}$ ligand, out of two donor atoms (N and S), only one donor atom is attached to metal as $M-SCN$ or $M-NCS$.