Question

The magnitude of $CFSE$ (Crystal Field Splitting Energy, $\Delta_{o}$) can be related to the configuration of $d$-orbitals in a coordination entity as

• A. if $\Delta_{o} <\, P$, the configuration is $t^{3}_{2g} e^{1}_{g}=$ weak field ligand and high spin complex
• B. if $\Delta_{o} >\, P$, the configuration is $t^{3}_{2g} e^{1}_{g}=$ strong field ligand and low spin complex
• C. if $\Delta_{o} >\, P$, the configuration is $t^{4} _{2g} e^{0}_{g}=$ strong field ligand and high spin complex
• D. if $\Delta_{o} = P$, the configuration is $t^{4}_{2g} e^{0}_{g}=$ strong field ligand and high spin complex

Answer 1

Answer: (A)

If $CFSE (\Delta_{0})<\, P$ (Energy required for pairing), the electrons do not pair up and fourth electron goes to $e_{g}$ of higher energy. Hence, high spin complex is formed. Pairing of electrons does not take place in case of weak field ligands.