UV-VISIBLE SPECTROSCOPY IN THE INTERPRETATION OF THE TAUTOMERIC EQUILIBRIUM OF '(BIS-3,5-DI-BROMO-SALICYLIDEN)-1,2-DIAMINOBENZENE AND THE REDOX ACTIVITY OF ITS CO(II) COMPLEX - A QUANTUM-CHEMICAL APPROACH

By means of quantum chemical calculations, the origin of the redox cap ability of '(bis-3,5-di-bromo-salicyliden)-1,2-diaminobenzene Co (II) complexes, of major interest in the catalytic reduction of naphtas, is analyzed. The geometry, electronic structure and UV-vis spectra of bo th the complex and the ligand are studied. AM1 and INDO/1 hamiltonians are used for the conformational analysis, whereas the UV-visible spec tra are accurately reproduced by means of WDO/S-CI calculations, justi fying the color of the ligand and offering an explanation to the catal ytic redox activity of the Co(II) complex, based on the electronic tra nsitions associated to the spectroscopic features and the electronic c haracteristics of the redox states.