The electron distribution in $d^{n}$ coordination complexes depends on magnitude of crystal field splitting, ( $∆_{0}$ ) and pairing energy (P). The condition which favours formation of high spin complexes is :

see full answer

21% of IItians & 23% of AIIMS delhi doctors are from Sri Chaitanya institute !!

An Intiative by Sri Chaitanya

$t_{2 g}^{4} e_{g}^{0}$

$Δ_{o} > P$

$Δ_{o} = P$

$Δ_{o} < P$

answer is B.

(Unlock A.I Detailed Solution for FREE)

Ready to Test Your Skills?

Check your Performance Today with our Free Mock Test used by Toppers!

Take Free Test

Detailed Solution

High spin complex means pairing does not occur.
This condition is possible only in presence of weak field ligands.
In octahedral complexes energy of $t_{2 g} < e_{g}$ .
In presence of weak field ligand, electrons progressively enter to $t_{2 g}$ until each of the three orbitals of $t_{2 g}$ are half-filled then fourth and fifth electrons enter into $e_{g}$ levels are half filled.
This condition is possible when $Δ_{o} < P$ .