Question

the complex ion NidppeCl2 can either have a tetrahedral geometry or a square planar geometry around the interior Ni2 ion. When tested, NidppeCl2 proved to be diamagnetic. Based on crystal field theory, what is the geometry around the central Ni ion

Answer 1

Square planar

Step-by-step explanation:

Ni^2+ is a d8 ion. It could exist in either a square planar or a tetrahedral geometry depending on the identity of the ligand. However, strong field ligands often lead to a square planar geometry owing to a greater crystal field splitting.

From the splitting diagrams of nickel II ion in tetrahedral and square planar geometries, it can easily be seen that a diamagnetic complex only arises from the square planar geometry.

Note that both tetrahedral and square planar geometries involve a coordination number of four.