Atmospheric Chemistry and Physics Discussions www.atmos-chem-phys-discuss.net 1680-7367 1680-7375 9 2 2009 10.5194/acpd-9-8857-2009 http://www.atmos-chem-phys-discuss.net/9/8857/2009/ http://www.atmos-chem-phys-discuss.net/9/8857/2009/acpd-9-8857-2009.html http://www.atmos-chem-phys-discuss.net/9/8857/2009/acpd-9-8857-2009.pdf 8857 8902 2009-04-03 Isoprene oxidation by nitrate radical: alkyl nitrate and secondary organic aerosol yields A. W. Rollins A. Kiendler-Scharr J. Fry T. Brauers S. S. Brown H.-P. Dorn W. P. Dubé H. Fuchs A. Mensah T. F. Mentel F. Rohrer R. Tillmann R. Wegener P. J. Wooldridge R. C. Cohen Department of Chemistry, University of California Berkeley, Berkeley, CA 94720, USA Department of Earth and Planetary Science, University of California Berkeley, Berkeley, CA 94720, USA Institute of Chemistry and Dynamic of the Geosphere, Forschungszentrum Jülich, Germany Chemical Sciences Division, NOAA Earth System Research Laboratory, Boulder, CO, USA Alkyl nitrates and secondary organic aerosol (SOA) produced during the oxidation of isoprene by nitrate radicals has been observed in the SAPHIR chamber. We find the yield of nitrates is 70&plusmn;8% from the isoprene+NO₃ reaction, and the yield for secondary dinitrates produced in the reaction of primary isoprene nitrates with NO₃ is 40&plusmn;20%. We find an effective rate constant for reaction of NO₃ with the group of first generation oxidation products to be 7&times;10^&minus;14 cm³ s^&minus;1. 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