title: Infrared detection of Criegee intermediates formed during the ozonolysis of β-pinene and their reactivity towards sulfur dioxide.
abstract: Recently, direct kinetic experiments have shown that the oxidation of sulfur dioxide to sulfur trioxide by reaction with stabilized Criegee intermediates (CIs) is an important source of sulfuric acid in the atmosphere. So far, only small CIs, generated in photolysis experiments, have been directly detected. Herein, it is shown that large, stabilized CIs can be detected in the gas phase by FTIR spectroscopy during the ozonolysis of β-pinene. Their transient absorption bands between 930 and 830 cm(-1) appear only in the initial phase of the ozonolysis reaction when the scavenging of stabilized CIs by the reaction products is slow. The large CIs react with sulfur dioxide to give sulfur trioxide and nopinone with a yield exceeding 80%. Reactant consumption and product formation in time-resolved β-pinene ozonolysis experiments in the presence of sulfur dioxide have been kinetically modeled. The results suggest a fast reaction of sulfur dioxide with CIs arising from β-pinene ozonolysis.
authors.affiliation: Institut für Physikalische Chemie, Universität Göttingen, Tammannstrasse 6, 37077 Göttingen (Germany).
authors.forename: Jennifer
authors.initials: J
authors.lastname: Ahrens
authors.forename: Philip T M
authors.initials: PT
authors.lastname: Carlsson
authors.forename: Nils
authors.initials: N
authors.lastname: Hertl
authors.forename: Matthias
authors.initials: M
authors.lastname: Olzmann
authors.forename: Mark
authors.initials: M
authors.lastname: Pfeifle
authors.forename: J Lennard
authors.initials: JL
authors.lastname: Wolf
authors.forename: Thomas
authors.initials: T
authors.lastname: Zeuch
mesh_terms: D000475:Alkenes / Q000737:chemistry; D000081008:Bicyclic Monoterpenes; D001643:Bridged Bicyclo Compounds / Q000737:chemistry*; D017665:Hydroxyl Radical / Q000737:chemistry; D039821:Monoterpenes / Q000737:chemistry*; D010084:Oxidation-Reduction; D010126:Ozone / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D013458:Sulfur Dioxide / Q000737:chemistry*; D013461:Sulfur Oxides / Q000138:chemical synthesis / Q000737:chemistry
chemical_list: D000475:Alkenes; D000081008:Bicyclic Monoterpenes; D001643:Bridged Bicyclo Compounds; D039821:Monoterpenes; D013461:Sulfur Oxides; D013458:Sulfur Dioxide; D017665:Hydroxyl Radical; C010789:beta-pinene; D010126:Ozone; C011118:sulfur trioxide
keywords: Criegee intermediates; IR spectroscopy; ozonolysis; tropospheric sulfur chemistry; β-pinene