In which of the following complex(s) spin only magnetic moment is independent, from the nature of ligand. (L=monodentate ligand) :

Options

A. `[overset(II)NiL_(4)]`
B. `[overset(II)NiL_(6)]`
C. `[overset(III)FeL_(6)]`
D. `[overset(III)CrL_(6)]`

Answer

B, D

Explanation

`Ni^(2+)(d^(8))`

CN=6 Only `sp^(3)d^(2)`
`Fe^(3+)(d^(6))C.N.=6` both `sp^(3)d^(2)` and `d^(2)sp^(3)` possible
`Cr^(3+)(d^(3))` only `d^(2)sp^(3)` (C.N.=6)