QJEEM23Che4b9: JEE Main 2023 Chemistry - Class 12 JEEM23Che4b9 Solution: Which of the following complex has a possibility to exist as…

Meridional (mer) isomerism is a type of geometrical isomerism found specifically in octahedral complexes, where three identical ligands occupy a meridian plane. Thus, it requires at least three identical bidentate or monodentate ligands.

Given the options, the complex that could potentially exist as a meridional isomer is :

Option D : $[\mathrm{Co}(\mathrm{NH}_{3})_{3}(\mathrm{NO}_{2})_{3}]$

In this complex, there are three $\mathrm{NH_3}$ and three $\mathrm{NO_2}$ ligands, allowing it to form a meridional configuration where either all three $\mathrm{NH_3}$ or all three $\mathrm{NO_2}$ ligands lie along a meridian plane.