Study of CW Laser Fluorescence Spectroscopy on Photodecomposion Process of Phenodiazophthopuinon Molecule

CW laser fluorescence spectroscopy was performed to study photodecomposion of phenodiazophthopuinon molecule . In order to search the physical chemistry process of photodecomposion, relationships between fluorescence intensity, laser power and concenrtation of solution were investigated in detail. Three fluorescence peaks at 530, 607.9 and 691.7nm were found. The spectra pattern and relative intensity of those peaks changed dramatically with laser power, exposure time and concentration of solutions. Fluorescence characteristics of original molecule and final product molecule which peaks at 607.9 and 530nm respectivelly were recognized and intermediate molecule whose fluorescene peaks at 691.7nm was also found. By proposed "CW laser fluorescence attenuation" method had recorded kinetic process of photodecomposion of original molecule in time and the analysis formula of photodecomposion was consequentially obtained from nonlinear data fitting of the attenuate curve. Experiment results show that four extinction channels govern the physical chemistry process of the photodecomposion: part of exciting photons makes some of original molecula decompose and consequentially produce intermediate molecule and final product molecule, while the others excite some of original molecula, internediate molecula and final product molecula to fluoresce.