title: Formation of secondary organic aerosol marker compounds from the photooxidation of isoprene and isoprene-derived alkene diols under low-NO(x) conditions.
abstract: In the present work, we have evaluated whether isomeric C5-alkene diols (1,2-dihydroxy-2-methyl-3-butene, 1,2-dihydroxy-3-methyl-3-butene, and 1,4-dihydroxy-2-methyl-2-butene (cis + trans)), which have first been detected upon photooxidation of isoprene in the absence of NO and are known to be formed in the ambient atmosphere, can serve as precursors for the 2-methyltetrols, C5-alkene triols, and 2-methylglyceric acid under low-NO(x) conditions. The C5-alkene diols were prepared following published synthesis procedures. It is shown that under the applied chamber conditions the isomeric C5-alkene diols give rise to 2-methyltetrols with different threo/erythro abundance ratios and that certain diols produce 2-methylglyceric acid, but that they do not form C5-alkene triols. Furthermore, it is shown that the photooxidation of isoprene under the applied chamber conditions employing photolysis of H2O2 under dry conditions yields relatively small amounts of C5-alkene triols compared to those of the 2-methyltetrols, unlike under ambient conditions. It is argued that the chamber conditions are not optimal for the formation of C5-epoxydiols, which serve as gas-phase precursors for the C5-alkene triols, and likely as in some previous studies favor the formation of C5-alkene diols as a result of RO2 + RO2 reactions.
authors.affiliation: Department of Pharmaceutical Sciences, University of Antwerp, Belgium.
authors.forename: Wu
authors.initials: W
authors.lastname: Wang
authors.affiliation: Leibniz-Institut für Troposphärenforschung, Leipzig, Germany.
authors.forename: Yoshiteru
authors.initials: Y
authors.lastname: Iinuma
authors.affiliation: Department of Pharmaceutical Sciences, University of Antwerp, Belgium.
authors.forename: Ariane
authors.initials: A
authors.lastname: Kahnt
authors.affiliation: Department of Pharmaceutical Sciences, University of Antwerp, Belgium.
authors.forename: Oxana
authors.initials: O
authors.lastname: Ryabtsova
authors.affiliation: Leibniz-Institut für Troposphärenforschung, Leipzig, Germany.
authors.forename: Anke
authors.initials: A
authors.lastname: Mutzel
authors.affiliation: Department of Pharmaceutical Sciences, University of Antwerp, Belgium.
authors.forename: Reinhilde
authors.initials: R
authors.lastname: Vermeylen
authors.affiliation: Department of Pharmaceutical Sciences, University of Antwerp, Belgium.
authors.forename: Pieter
authors.initials: P
authors.lastname: Van der Veken
authors.affiliation: Department of Pharmaceutical Sciences, University of Antwerp, Belgium.
authors.forename: Willy
authors.initials: W
authors.lastname: Maenhaut
authors.affiliation: Leibniz-Institut für Troposphärenforschung, Leipzig, Germany.
authors.forename: Hartmut
authors.initials: H
authors.lastname: Herrmann
authors.affiliation: Department of Pharmaceutical Sciences, University of Antwerp, Belgium.
authors.forename: Magda
authors.initials: M
authors.lastname: Claeys
mesh_terms: D000336:Aerosols / Q000737:chemistry*; D000475:Alkenes / Q000737:chemistry*; D002070:Butadienes / Q000737:chemistry*; D045782:Hemiterpenes / Q000737:chemistry*; D009589:Nitrogen Oxides / Q000737:chemistry*; D009930:Organic Chemicals / Q000737:chemistry*; D010084:Oxidation-Reduction; D010420:Pentanes / Q000737:chemistry*; D055668:Photochemical Processes
chemical_list: D000336:Aerosols; D000475:Alkenes; D002070:Butadienes; D045782:Hemiterpenes; D009589:Nitrogen Oxides; D009930:Organic Chemicals; D010420:Pentanes; C005059:isoprene