Question

Describe linkage isomerism with an example.

Answer 1

Linkage isomerism is a type of structural isomerism observed in coordination compounds where an ambidentate ligand binds to the central metal ion through different atoms.

Example: [Co(NH₃)₅NO₂]Cl₂ and [Co(NH₃)₅ONO]Cl₂ 

In this example, the ligand nitrite \[\ce{NO^-2}\] can bind to the metal in two different ways:

• Through the nitrogen atom (as nitro: -NO₂).
• Through the oxygen atom (as nitrito: -ONO).

These two complexes are linkage isomers because the nitrite ligand can coordinate to the central metal via either its nitrogen or oxygen atom, resulting in different isomers.