PHOTOCHEMICAL PROPERTIES OF SOME COMPLEX AND SIMPLE CHEMICAL MOLECULES OF INDUSTRIAL POTENTIALS

Abstract

Chapter one includes a general introduction about fluorescence, variables affecting fluorescence, fluorescence quenching by foreign substances, mechanisms of excitation energy transfer, photosensitization, photostability, different analytical methods for .determination of some transition metal ions and a literature

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Chapter two includes the materials, Instrumentation, preparations and general procedures, different methods of data analysis, data transfer and representation using both Excel and Origin version 6. Chapter three deals with the obtained results and discussions. lt has been shown that the absorption spectrum of 8-AQ in acetonitrile has an absorption peak at 340 nm The presence of an auxochromic b'TOup (amino group) brings about a bathochromic effect, so shifting the absorption band to the longer wavelength. The excitation spectrum has two excitation peaks (270 and 341 nm ) and the fluorescence spectrum has an emission peak (470 nm) The fluorescence spectrum of 8-AQ is a mirror image of its excitation spectrum.

When metal ions (Co2+, Ni 2+, Cu2+ and Zn2

) are added to the

ligand 8-AQ a nontluorescent complex is formed, so the observed fluorescence is only from the uncomplexed 8- aminoquinoline. The fluorescence data are treated as mentioned in experimental section. The figures show the deviation from SV plots and the modified SV plots. The results could be explained on the basis of complex formation both in the ground state and in the first singlet excited state. The formation constant of the formed complexes in the excited state are determined from the least squares plots fitting of Hill equation given in chapter two.