SYNTHESIS AND SPECTRAL STUDIES OF SOME RARE-EARTH-METAL COMPLEXES OF PYRAZINECARBOXYLIC HYDRAZIDE

Trivalent lanthanide metal complexes of pyrazine carboxylic hydrazide (pyzh) of the type [Ln(pyzh)3Cl2]Cl.EtOH where Ln = La, Pr, Nd, Sm, Eu , Gd, Tb, Dy and Y have been synthesized and their structures studied by elemental analyses, electrical conductance, magnetic susceptibility , electronic, infrared, H-1 and C-13 NMR spectral techniques. The bond ing parameters betaBAR, b1/2, %delta and eta were calculated from the electronic spectral (hypersensitive) bands of Pr(III), Nd(III), Sm(III ), Eu(III) and Dy(III) complexes. The spectral data suggest an eight-c oordination around the metal ion and a neutral bidentate nature of pyz h in the complexes.