Thermal and spectral studies on complexes derived from tetradentate Schiff bases

Journal of Thermal Analysis and Calorimetry (Impact Factor: 1.98). 96(3):961-969. DOI: 10.1007/s10973-009-0062-z

ABSTRACT Several new complexes of Schiff bases ligands H4La and H4Lb with transition metal ions such as Cr(III), Fe(III), Co(II) and Zn(II) are synthesized. Elemental analysis, infrared, UV–Vis
and thermal analysis, as well as conductivity and magnetic susceptibility measurements are used to elucidate the structure
of the newly prepared metal complexes. A square planar geometry is suggested for Zn(II) complexes, while an octahedral geometry
suggested for the Cr(III), Fe(III) and Co(II) complexes. The thermal decomposition of complexes was found to be first order
reaction and the thermodynamic parameters corresponding to the different decomposition steps were reported.

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