Question

Why is the contribution of orbital motion to paramagnetism not quenched in
lanthanide ions ? Explain.

Answer 1

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Answer 2

Because in lanthenoids due to the presence of unpaired electrons in 4f-orbitals all the lanthenoids ions show paramegnatic behaviour except following ions of Lanthenoids series
La3+, L2+, Yb3+ and Cu3+. Modern theories have proven that magnetic behaviour is concerned not only with spin motion but also orbital motion too. Only unpaired electrons can perform these motions.