Bidentate Ligands

Bidentate ligands have two donor atoms which allow them to bind to a central metal atom or ion at two points. Common examples of bidentate ligands are ethylenediamine (en), and the oxalate ion (ox). Shown below is a diagram of ethylenediamine: the nitrogen (blue) atoms on the edges each have two free electrons that can be used to bond to a central metal atom or ion.

Figure 1 : Ethylenediamine (en) is an example of a bidentate ligand.

Ethylenediamine (en) is a bidentate ligand that forms a five-membered ring in coordinating to a metal ion M