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A. Abu-Hussen, W. Linert:
"Redox, thermodynamic and spectroscopic of some transition metal complexes containing heterocyclic Schiff base ligands";
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 74 (2009), 214 - 223.

Complexes of two series of Schiff base ligands, H2La and H2Lb derived from the reaction of 2,6-diacetyl
pyridine with semicarbazide, H2La and thiosemicarbazide, H2Lb, with the metal ions, Co(II), Ni(II), Cu(II),
VO(IV) and UO2(VI) have been prepared. The ligands are characterized by elemental analysis, IR, UV-vis
and 1H NMR. The structures of the complexes are investigated with the IR, UV-vis, X-band ESR spectra,
1H NMR and thermal gravimetric analysis as well as conductivity and magnetic moment measurements.
The IR-spectra reveal the presence of variable modes of chelation for the investigated ligands. A variety
of binuclear or mononuclear complexes were obtained with the two ligands in tri-, tetra or pentadentate
forms. The bonding sites are the pyridine nitrogen, two azomethine nitrogen atoms and ketonic oxygen in
case of H2La or sulphur atoms in case of H2Lb. The Coats-Redfern equation has been used to calculate the
kinetic and thermodynamic parameters for the different thermal decomposition steps of somecomplexes.
Cyclic voltammograms of Co(II) and Ni(II) show quasi-reversible peaks. The redox properties and the
nature of the electro-active species of the complexes have been characterized.

http://dx.doi.org/10.1016/j.saa.2009.06.023