Q52 · CSIR NET Chemistry, December 2011
Paper: CSIR NET December 2011 · Subject: Inorganic Chemistry · Chapter: Lanthanides and Actinides · Topic: Lanthanides & Actinides – General · Marks: 2 · Difficulty: Medium
The actual magnetic moment shows a large deviation from the spin-only formula in the case of
(a)$\mathrm{Ti}^{+}$
(b)$\mathrm{V}^{3+}$
(c)$\mathrm{Gd}^{3+}$
(d)$\mathrm{Sm}^{3+}$
Answer
Answer: D ✓ checked by 4AB · confidence high
Explanation
Sm³⁺ (f⁵, ⁶H₅/₂) has low-lying J levels that are thermally populated, so the observed moment (≈1.5 BM) departs strongly from both the spin-only and the ground-J value; Ti³⁺, V³⁺ and Gd³⁺ do not.
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