FLUORESCENCE SPECTROSCOPY AND RADIATIONLESS PROCESSES IN $CF_{3}NO$

This work is supported by the National Science Foundation.Author Institution: Department of Chemistry, Northwestern UniversityThe $CF_{3}NO$ molecule is a blue gas with a weak absorption from 520 to 720 nm that occurs by the promotion of a nitrogen nonbonding electron to the NO antibonding orbital. We have measured the collision free fluorescence lifetime with a tunable mode-locked, cavity dumped dye laser and find lifetimes that range from 90 to 0.2 nsec as a function of vibrational level. The excited state is vibrationally relaxed by collision and our initial comparisons of high pressure excitation spectra with absorption spectra suggest that photodissociation is probably occurring by both a rapid predissociative channel and another channel such as internal conversion or intersystem crossing. We will present time and wavelength resolved fluorescence spectra, high resolution laser excitation spectra and photochemical evidence to refine the excited state vibrational assignments and mechanisms for excited state relaxation