The correct order of the calculated spin-only magnetic moments of complexes (A) to (D) is : (A) (B) (C) (D)
As we have learnt,
contains which has a configuration having and
contains which has a configuration. In a weak ligand field, it has and hence has
contains which has a configuration. In a strong ligand field, these electrons get paired up and hence and
contains which has a configuration. These electrons get paired in the presence of strong ligand like and hence, and correspondingly .
Therefore, the correct order of spin only magnetic moment of the complexes is
Therefore, Option(4) is correct.