الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
It is concerned with the results and discussion. The infrared spectra assigned the different modes of vibrations of the fundamental functional groups in the compounds under consideration. On complexation, the shifts in the characteristic IR frequencies reveal that alloxan coordinates to the central metal ion in bidentate ON pattern, whereas ninhydrin as alterdentate ligand through hydroxyl oxygen and carbonyl oxygen either C(1)=O or C(3)=O. The analytical, electronic spectra, and magnetic values suggest that all complexes are of 1:1 (M:L) stoichiometry and of octahedral geometry except in the case of nickel complexes of tetrahedral shape.The thermal analysis studies (TGA, DTA, and DSC) of ligands and some of their synthesized complexes, were examined. The thermodynamic activation parameters (energy of activation ΔE*, enthalpy ΔH*, entropy ΔS*, and free energy ΔG*) were calculated from the thermogravimetric (TGA) curves for selected complexes. The stabilities of some complexes were checked using thermogravimetric analysis and thermodynamic calculations. The thermal processes proceed in complicated mechanisms with more ordered transition states. The first decomposition step corresponds to the loss of inner water molecules or elimination of small molecules and is usually ended by the formation of metal oxide residue.