Question

Which type of isomerism does this complex $[\mathrm{Co}{\left(\mathrm{en}\right)}_3{]}^{3+}$ exhibit?

Answer 1

Optical Isomerism

• Optical isomers are mirror images that cannot be superimposed on one another.
• These are called enantiomers.

Isomerism in $[\mathrm{Co}{\left(\mathrm{en}\right)}_3{]}^{3+}$

• The complex $[\mathrm{Co}{\left(\mathrm{en}\right)}_3{]}^{3+}$shows optical isomerism.
• Dextro (d) and laevo (l) refer to the directions in which the two forms rotate the plane of polarised light in a polarimeter (d rotates to the right, l rotates to the left).
• Optical isomerism is common in octahedral complexes involving bidentate ligands as shown in the diagram given below:-