SPECTRAL AND KINETIC STUDIES OF FREE RADICALS OF ATMOSPHERIC INTEREST

A review of spectral and kinetic studies of free radicals of atmospheric interest in this laboratory during the past decade is given. The spectral experiments involved infrared absorption and laser-induced fluorescence in the UV-visible spectral region to detect radicals in a flow reactor, a supersonic jet or isolated in matrices. IR absorption of several reaction intermediates and vibronic analyses of many electronic transitions have been reported. The discharge-flow and the laser-photolysis techniques were employed to investigate the kinetics of radical reactions which are important in the atmosphere; the temperature dependence of the rate coefficients was determined. Information on the rate coefficients of several important reactions has been reported. The detailed rate coefficients of some equilibrium reactions involving OH at various temperatures were determined from the bi-exponential temporal profiles of the concentration of OH; DELTAH and DELTAS of the reaction were consequently obtained.