Number of ambidentate ligands in a representative metal complex M(en)(SCN)$$_4$$ is ______. [en = ethylenediamine]

An ambidentate ligand is a ligand that can coordinate to a metal through two different donor atoms.

In the complex $$M(en)(SCN)_4$$:

en (ethylenediamine): H₂N-CH₂-CH₂-NH₂. It coordinates through two nitrogen atoms. Both donor atoms are the same element (N), so it is a bidentate ligand but NOT ambidentate.

SCN⁻ (thiocyanate): This is an ambidentate ligand as it can coordinate through either:

- Sulfur atom (thiocyanato, S-bonded: M-SCN)

- Nitrogen atom (isothiocyanato, N-bonded: M-NCS)

There are 4 SCN⁻ ligands in the complex, and each one is ambidentate.

The number of ambidentate ligands is 4.