| Title: | Gas-to-Particle Partitioning of Cyclohexene- and alpha-Pinene-Derived Highly Oxygenated Dimers Evaluated Using COSMOtherm |
| Author(s): | Hyttinen N; Wolf M; Rissanen MP; Ehn M; Perakyla O; Kurten T; Prisle NL; |
| Address: | "Nano and Molecular Systems Research Unit, University of Oulu, 90014 Oulu, Finland. Department of Applied Physics, University of Eastern Finland, 70211 Kuopio, Finland. Department of Chemistry and Institute for Atmospheric and Earth System Research (INAR), University of Helsinki, 00014 Helsinki, Finland. Aerosol Physics Laboratory, Physics Unit, Tampere University, 33720 Tampere, Finland. Institute for Atmospheric and Earth System Research (INAR)/Physics, University of Helsinki, 00014 Helsinki, Finland. Center for Atmospheric Research, University of Oulu, 90014 Oulu, Finland" |
| ISSN/ISBN: | 1520-5215 (Electronic) 1089-5639 (Print) 1089-5639 (Linking) |
| Abstract: | "Oxidized organic compounds are expected to contribute to secondary organic aerosol (SOA) if they have sufficiently low volatilities. We estimated saturation vapor pressures and activity coefficients (at infinite dilution in water and a model water-insoluble organic phase) of cyclohexene- and alpha-pinene-derived accretion products, 'dimers', using the COSMOtherm19 program. We found that these two property estimates correlate with the number of hydrogen bond-donating functional groups and oxygen atoms in the compound. In contrast, when the number of H-bond donors is fixed, no clear differences are seen either between functional group types (e.g., OH or OOH as H-bond donors) or the formation mechanisms (e.g., gas-phase radical recombination vs liquid-phase closed-shell esterification). For the cyclohexene-derived dimers studied here, COSMOtherm19 predicts lower vapor pressures than the SIMPOL.1 group-contribution method in contrast to previous COSMOtherm estimates using older parameterizations and nonsystematic conformer sampling. The studied dimers can be classified as low, extremely low, or ultra-low-volatility organic compounds based on their estimated saturation mass concentrations. In the presence of aqueous and organic aerosol particles, all of the studied dimers are likely to partition into the particle phase and thereby contribute to SOA formation" |
| Notes: | "PubMed-not-MEDLINEHyttinen, Noora Wolf, Matthieu Rissanen, Matti P Ehn, Mikael Perakyla, Otso Kurten, Theo Prisle, Nonne L eng 2021/04/23 J Phys Chem A. 2021 May 6; 125(17):3726-3738. doi: 10.1021/acs.jpca.0c11328. Epub 2021 Apr 22" |
