Synthesis and characterization of some lanthanide complexes of 2,6-diacetylpyridine 2-thenoylnicotinoyldihydrazone

The complexes of the type [Ln(H(2)dapthnh)Cl(H2O)(2)]Cl-2[Ln=La, Pr, Nd, Sm , Eu, Gd, Tb and Dy; H(2)dapthnh = 2,6-diacetylpyridine-2-thenoylnicotinoyl dihydrazone] have been synthesized by reacting [Ln(Hdapth)Cl-2(H2O)(3)]Cl [ Hdapth=2,6-diacetylpyridinemono(2-thenoylhydrazone) with nicotinoylhydrazin e in ethanol and characterized by analytical, molar conductance, IR,H-1 NMR , electronic and FAB mass data. The position and shape of the hypersensitiv e transitions I-4(9/2) --> (4)G(5/2), (2)G(7/2) in the neodymium complex in dicate eight coordinate geometry around the Ln(III) ions. The symmetry of t he eight coordinate Eu(III) and Tb(III) complexes has been determined from the emission spectra.