The UV-visible absorption cross-sections of IONO2 J. C. Mössinger1, D. M. Rowley*, and R. A. Cox1 1Centre for Atmospheric Science, Chemistry Department, University of Cambridge, UK *present address: Chemistry Department, University College London, UK
Abstract. The UV-visible absorption spectrum of gaseous
IONO2 has been measured over the wavelength range 245--415 nm using the technique of laser photolysis with time-resolved
UV-visible absorption spectroscopy. IONO2
was produced in situ in the gas phase by laser flash photolysis of NO2/CF3I/N2 mixtures. Post flash spectra were deconvolved to
remove contributions to the observed absorption from other reactant and product species.
The resulting spectrum attributed to IONO2
consists of several overlapping broad absorption bands. Assuming a quantum yield of unity for
IONO2photolysis, model calculations show that during sunlit hours at noon,
53° N, the first order solar photolysis rate coefficient (J value) for IONO2
is 4.0 x 10-2 s-1.
Citation: Mössinger, J. C., Rowley, D. M., and Cox, R. A.: The UV-visible absorption cross-sections of IONO2, Atmos. Chem. Phys., 2, 227-234, doi:10.5194/acp-2-227-2002, 2002.