`[NiCl_(2){P(C_(2)H_(5))_(2)(C_(6)H_(5))}_(2)]` exhibits temperature dependent magnetic behaviour. The coordination geometries of `Ni^(2+)` in the paramagnetic and diamagnetic states are:

Options

A. tetrahedral and tetrahedral
B. square planar and square planar
C. tetrahedral and square planar
D. square planar and tetrahedral

Answer

C

Explanation

`[NiCl_(2){P(C_(2)H_(5))_(2)(C_(6)H_(5))}_(2)]`
contains `Ni^(2+)` having the electronic configuration as under :

In the high spin state, it is paramagnetic with `sp^(3)` hybridization giving tetrahedral geometry. In the low spin state (unpaired electrons pair up), it is diamagnetic with `dsp^(2)` hybridization giving square planar geometry.