ACPD Atmospheric Chemistry and Physics Discussions ACPD Atmos. Chem. Phys. Discuss. 1680-7375 Göttingen, Germany 10.5194/acpd-6-10275-2006 Temperature dependence of secondary organic aerosol yield from the ozonolysis of β-pinene Stenby C. 2 1 Pöschl U. 3 von Hessberg P. 2 1 Bilde M. 2 Nielsen O. J. 2 Moortgat G. K. 1 Atmospheric Chemistry Department, Max Planck Institute for Chemistry, J.J. Becherweg 29, 55128 Mainz, Germany Copenhagen Center for Atmospheric Research, Department of Chemistry, University of Copenhagen, Universitetsparken 5, 2100 Copenhagen Ø, Denmark Biogeochemistry Department, Max Planck Institute for Chemistry, J.J. Becherweg 29, 55128 Mainz, Germany 16 10 2006 6 5 10275 10297 Copyright: © 2006 C. Stenby et al. 2006 This work is licensed under the Creative Commons Attribution-NonCommercial-ShareAlike 2.5 Generic License. To view a copy of this licence, visit https://creativecommons.org/licenses/by-nc-sa/2.5/ This article is available from https://acp.copernicus.org/preprints/6/10275/2006/acpd-6-10275-2006.html The full text article is available as a PDF file from https://acp.copernicus.org/preprints/6/10275/2006/acpd-6-10275-2006.pdf

The temperature dependence of secondary organic aerosol (SOA) formation from ozonolysis of &beta;-pinene was studied in a flow reactor at 263&ndash;303 K and 1007 hPa. The observed SOA yields were of similar magnitude as predicted by a two-product model based on detailed gas phase chemistry (Jenkin, 2004), reaching maximum values of 0.22&ndash;0.39 at high particle mass concentrations. However, the measurement data exhibited significant deviations (up to 50%) from the predicted linear dependence on inverse temperature. When fitting the measurement data with a two-product model, we found that both the partitioning coefficients (<i>K<sub>om,i</sub></i>) and the stoichiometric yields (&alpha;<sub><i>i</i></sub>) of the low-volatile and semi-volatile species vary with temperature. The results indicate that not only the reaction product vapour pressures but also the relative contributions of different gas-phase or multiphase reaction channels are dependent on temperature. We suggest that the modelling of secondary organic aerosol formation in the atmosphere needs to take into account the effects of temperature on the pathways and kinetics of the involved chemical reactions as well as on the gas-particle partitioning of the reaction products.