Studies on Mixed Ligand Complexes of Lanthanide(III) Ions

Abstract

As part of our research programme, we have prepared and characterized a few nitrato, thiocyanato and perchlorato complexes of lanthanide(III) ions with ligands, viz., a Schiff base derived from p-anisidine and vanillin and diphenyl sulphoxide. The complexes were characterized by the measurement of electrical conductances and magnetic susceptibilities, molecular mass and metal percentage and spectral analysis. The thermal
decompositions were studied by TG and DTG techniques. The thiocyanato
complexes were prepared by substitution method from nitrato complexes.
p-Anisidine-vanillin (HDDA) and diphenyl sulphoxide (DPSO) are coordinated
to the metal ion in unidentate fashion. All the anions were involved
in coordination in these complexes. Thus they were found to have non-electrolytic
behaviour with composition [Ln(HDDA)₂(DPSO)X₃] where
X = NO^–₃ or SCN^–. Perchlorato complexes were prepared from metal perchlorate
as done in the case of nitrato complexes. They were found to have
electrical conductance which corresponds to 1 : 1 electrolyte. Hence one
of the perchlorate ions is outside the coordination sphere. The composition
of this complex is found to be [Ln(HDDA)₃(DPSO)(ClO₄)₂]ClO₄.