Chemistry - Coordination Chemistry Question with Solution | TestHub
Select the correct graph between the spin-only magnetic moment of an octahedral complex and the number of d-electrons, with weak field ligands and strong field ligands respectively.
Options:
Answer:
Solution:
The spin-only magnetic moment is μ = √[n(n+2)] BM, where n is the number of unpaired electrons. So μ increases with n but is not directly proportional to it. We take an octahedral complex.
Weak field ligand (high spin): pairing does not occur early, so n rises from d¹ to d⁵ (n = 5) and then falls to d¹⁰ (n = 0), giving a single peak at d⁵.
Strong field ligand (low spin): electrons pair up in the lower t₂g orbitals first, so n peaks at d³ (n = 3), drops to 0 at d⁶, rises again to a smaller peak at d⁸ (n = 2), and finally drops to 0 at d¹⁰.
The graph with these two curves is option (A).
