Synthesis and Physico-chemical Investigations of Some Seven Coordinated Complexes of Lanthanides(III) Chloride Derived from Hydrazones of Isonicotinic Acid Hydrazide

Abstract

The present work describes the synthesis of lanthanide(III) chloride coordination complexes of hydrazones of isonicotinic acid hydrazide viz., N-isonicotinamido-2-hydroxybenzalaldimine (INH-SAL), N-isonicotinamido-3-methoxy-4-hydroxybenzalaldimine (INH-VAN), N- isonicotinamido-2-hydroxy- 1-naphthalaldimine (INH-Naph) with with general composition [Ln(L)₂Cl₃] (Ln = La, Pr, Nd, Sm, Gd, Tb or Dy; L = INH-SAL, INH-VAN or INH-Naph). All these coordination compounds were characterized by elemental analyses, molar mass determination, magnetic susceptibility, infrared and electronic spectra. The infrared studies show that all the three hydrazones behave as bidentate with carbonyl-oxygen and azomethine nitrogen as two coordination sites. In all these coordination compounds the central metal displays a coordination number seven. Thermal properties of these compounds were also investigated.