HR: 08:52h
AN: A11C-04    [Abstracts]
TI: Laboratory Studies of Atmospheric Iodine Photochemistry
AU: Gravestock, T
EM: tomg@chemistry.leeds.ac.uk
AF: Department of Chemistry, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT United Kingdom
AU: Heard, D
EM: d.e.heard@leeds.ac.uk
AF: Department of Chemistry, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT United Kingdom
AU: * Bloss, W
EM: w.j.bloss@leeds.ac.uk
AF: Department of Chemistry, University of Leeds, Woodhouse Lane, Leeds, LS2 9JT United Kingdom
AB: Iodine species are thought to play a role in the chemistry and composition of the marine boundary layer, through their influence upon the abundance of oxidants such as OH, their participation in ozone destruction cycles and their involvement in new particle formation; however many key aspects of the photochemical and kinetic parameters relevant to this chemistry are poorly known. We report results of laboratory investigations into several aspects of gas-phase iodine oxide photochemistry, aiming to elucidate some of the remaining uncertainties in iodine chemistry. The technique of laser photolysis / UV absorption spectroscopy has been used to obtain new data on the absorption spectra of I2O2 and OIO, which are compared with previous studies of the IO self-reaction. Results from a laser photolysis / laser induced fluorescence study of the CH2I2 / O2 reaction system are also described, in which we find no evidence for the formation of IO from the CH2I + O2 reaction, in contrast to recent findings. The implications for atmospheric iodine chemistry are discussed.
DE: 0300 ATMOSPHERIC COMPOSITION AND STRUCTURE
DE: 0317 Chemical kinetic and photochemical properties
DE: 0365 Troposphere: composition and chemistry
SC: Atmospheric Sciences [A]
MN: Fall Meeting 2005