Synthesis, Spectral Characterization and photo Thermal Decomposition Studies of New Hetrocyclic Azo Dye Compound Derived From Imidazole with Some Transition Metal Complexes.

New heterocyclic azo dye ligand 2-[2(-)- (4,5- dimethoxy carboxy phenyl) azo ]- Imidazole, (DMCPAI=HL) was prepared by coupling between a diazonium chloride solution of 2- amino - 4,5- dimethoxy benzoic acid with imidazole in alkaline ethanolic solution. Eight complexes with Cr(III), Mn(II) , Co(III) ,Ni(II) ,Cu(II) ,Zn(II) ,Cd(II) and Hg(II) ions were prepared and characterized using available techniques such as elemental analysis , Mass spectral, H-1- NMR, FT- IR, UV-Visb.,X- ray, TGA, SEM, molar conductance measurments and magnetic susceptibility. The analytical data show that the ligand behaves as neutral tridentate (N, N,O) ligand forming chelates with 1:2 ; [Metal : ligand] in all metal Complexes. The molar conductance data for all complexes are nonelectrolyte expected Cr(III) and Co(III) Complexes are 1:1 electrolyte. Octahedral geometry is suggested for metal complexes and d(2)sp(3) or sp(3)d(2) hybridization. Decomposition kinetics was studies photochemical for metal complexes through irradiation solution at wavelength 365 nm at 25 degrees C for 1 hour in ethanol was found to be the reaction from first order also. The calculated rate constant photolysis (k(d)) mediated follow spectral changes during the process of irradiation. The thermal analysis (TGA), SEM and X-ray diffraction are explained and discussed.