A new Mefenamic acid derivative [(4-amino-5-(2-(2,3- dimethylphenyl)aminophnyl)-1,2,4-triazole-3-thion](L) , was synthesized and characterized by (FT-IR) , UV-Vis and 1H ,13C-NMR Spectroscopy as well as elemental analysis (C.H.N).[L] has been used as a chelating ligand to prepare some complexes of (Co(ІІ), Ni(П), Cu(П), Zn(II)and Cd(II) ions .The prepared complexes were identified and their geometrical were suggested in solid state by using (FT-IR) and (UV-Vis) spectroscopy ,elemental analysis(C.H.N), Flame atomic absorption technique, in addition to magnetic susceptibility and conductivity measurements . The work also include a theoretical treatment of the formed complexes in the gas phase, this was done using the (hyperchem-8) program for the molecular mechanics and semi-empirical calculations. The heat of formation (ΔHf○) and binding energy (ΔEb) for ligand and their complexes were calculated by (PM3) method at 298 K○. It was found that the ligand [L] and its metal complexes were stable, which agreed well with the experimental studies in solid state. Furthermore the electrostatic potential of the free ligand [L] was calculated to investigate the reactive sites of the molecules. PM3 were used to evaluate the bond length and vibrational spectra for the ligand [L] and their metal complexes then comparing with the experimental values.
The work, which also included the induce Photostabilization of (PVC) film in air was investigated in the absence and presence of [L] and its complexes with transition metals (Co(ІІ), Ni(ІІ), Cu(ІІ), Zn(II)and Cd(II) by accelerated weathering tester. Polymer has been mixed with these complexes in solvent which containing of complex 0.5 % by weight. The photostabilization activity of these compounds was determined by monitoring the carbonyl (ICO),polyene(Ipo) and hydroxyl (IOH) indexes, weight loss method with irradiation time. It was found that the (ICO) (Ipo) and (IOH) indexes values increased with irradiation time and this increase depend on the type of additives.