Showing papers by "Bachcha Singh published in 2003"

Reaction of Coordinated Ligands. III. Synthesis and Characterization of Some Lanthanide Complexes of 2,6‐Diacetylpyridine‐2‐thenoylpicolinoyl Dihydrazone

Abstract: A new ligand, 2,6‐diacetylpyridine‐2‐thenoylpicolynoyl dihydrazone (H2dapthph), has been prepared. Complexes of the type [Ln(H2dapthph)Cl2]Cl (Ln = La, Pr, Nd, Sm, Eu, Gd, Tb and Dy) have been synthesized and characterized by analytical, molar conductance, FAB mass, IR, NMR, electronic and emission spectral data. The bonding sites of the hydrazone are deduced from IR and NMR spectra and the ligand is found to bond to the metal ion in a hexadentate fashion. Electronic spectra of the complexes have been analyzed and the spectral parameters viz. nephelauxetic ratio (β), bonding parameter (b1/2), Sinha parameter (δ%), angular overlap covalency (η) and oscillator strength (P) were calculated and discussed. The symmetry around the Ln(III) ions is indicated from emission spectra of the Eu(III) complex.