Question

The total number of possible isomers for squareplanar $\left[ Pt ( Cl )\left( NO _{2}\right)\left( NO _{3}\right)( SCN )\right]^{2-}$ is:

• A. 16
• B. 12
• C. 8
• D. 24

Answer 1

Answer: (B)

The square-planar complex of type $[ Mabcd ]^{ nt }$, where all four ligands are different, has 3 geometrical isomers. But if one of the ligands is ambidentate, then $2 \times 3=6$ geometrical isomers are possible.

Here, two ligands are ambidentate, then $4 \times 3=12$ geometrical isomers are possible.
In our example, both $NO _{2}^{-}$and $SCN ^{-}$are ambidentate ligands.
Hence option B is correct.
The total number of possible isomers for square-planar $\left[ Pt ( Cl )\left( NO _{2}\right)\left( NO _{3}\right)( SCN )\right]^{2-}$ is $12 .$