Identify the homoleptic complexes with odd number of d electrons in the central metal : (A) $$[FeO_4]^{2-}$$ (B) $$[Fe(CN)_6]^{3-}$$ (C) $$ [Fe(CN)_5NO]^{2-}$$ (D) $$[CoCl_4]^{2-}$$ (E) $$ [Co(H_2O)_3F_3]$$ Choose the correct answer from the options given below :

A homoleptic complex has only one type of ligand. We need to identify those with odd number of d electrons.

(A) $$[FeO_4]^{2-}$$: Fe is in +6 oxidation state ($$d^2$$). Homoleptic (only O ligands). d-electrons = 2 (even). Not selected.

(B) $$[Fe(CN)_6]^{3-}$$: Fe is in +3 oxidation state ($$d^5$$). Homoleptic (only CN ligands). d-electrons = 5 (odd). ✓

(C) $$[Fe(CN)_5NO]^{2-}$$: Has two types of ligands (CN and NO). Not homoleptic. Not selected.

(D) $$[CoCl_4]^{2-}$$: Co is in +2 oxidation state ($$d^7$$). Homoleptic (only Cl ligands). d-electrons = 7 (odd). ✓

(E) $$[Co(H_2O)_3F_3]$$: Has two types of ligands (H₂O and F). Not homoleptic. Not selected.

The correct answer is Option 3: (B) and (D) only.