Development of a detailed chemical mechanism (MCMv3.1) for the atmospheric oxidation of aromatic hydrocarbons C. Bloss1, V. Wagner1, M. E. Jenkin2, R. Volkamer3,*, W. J. Bloss1, J. D. Lee1,**, D. E. Heard1, K. Wirtz4, M. Martin-Reviejo4, G. Rea5, J. C. Wenger5, and M. J. Pilling1 1School of Chemistry, University of Leeds, Leeds LS2 9JT, UK984 2Imperial College London, Silwood Park, Ascot, Berkshire SL5 7PY, UK 3Institut für Umweltphysik, University of Heidelberg, INF 229, 69120 Heidelberg, Germany 4Centro de Estudios Ambientales del Mediterraneo, C. Charles R. Darwin 14, 46980 Paterna, Spain 5Department of Chemistry, National University of Ireland, University College Cork, Cork, Ireland *now at: Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, 77 Massachusetts Ave., Cambridge, MA 02139-4307, USA **now at: Department of Chemistry, University of York, York, YO10 5DD, UK
Abstract. The Master Chemical Mechanism has been updated from MCMv3 to MCMv3.1 in
order to take into account recent improvements in the understanding of
aromatic photo-oxidation. Newly available kinetic and product data from the
literature have been incorporated into the mechanism. In particular, the
degradation mechanisms for hydroxyarenes have been revised following the
observation of high yields of ring-retained products, and product studies of
aromatic oxidation under relatively low NOx conditions have provided
new information on the branching ratios to first generation products.
Experiments have been carried out at the European Photoreactor (EUPHORE) to
investigate key subsets of the toluene system. These results have been used
to test our understanding of toluene oxidation, and, where possible, refine
the degradation mechanisms. The evaluation of MCMv3 and MCMv3.1 using data
on benzene, toluene, p-xylene and 1,3,5-trimethylbenzene photosmog systems is
described in a companion paper, and significant model shortcomings are
identified. Ideas for additional modifications to the mechanisms, and for
future experiments to further our knowledge of the details of aromatic
photo-oxidation are discussed.
Citation: Bloss, C., Wagner, V., Jenkin, M. E., Volkamer, R., Bloss, W. J., Lee, J. D., Heard, D. E., Wirtz, K., Martin-Reviejo, M., Rea, G., Wenger, J. C., and Pilling, M. J.: Development of a detailed chemical mechanism (MCMv3.1) for the atmospheric oxidation of aromatic hydrocarbons, Atmos. Chem. Phys., 5, 641-664, doi:10.5194/acp-5-641-2005, 2005.