title: Determination of gas-phase ozonolysis rate coefficients of a number of sesquiterpenes at elevated temperatures using the relative rate method.
abstract: The rates of ozonolysis of four sesquiterpenes, β-caryophyllene, α-humulene, isolongifolene and α-cedrene, are determined in the gas phase at an elevated temperature of 366 ± 3 K and a pressure of ~780 Torr using the EXTreme RAnge chamber (EXTRA). The experimentally obtained rate coefficients agree with extrapolated room temperature rate coefficients for isolongifolene and α-cedrene but not for β-caryophyllene and α-humulene, which were found to be three orders of magnitude slower than this in the literature. These new measurements support the hypothesis that operating under ambient conditions, kinetic measurements of condensable species can be influenced adversely by heterogeneous processes and should therefore be treated with caution.
authors.affiliation: Centre for Atmospheric Science, School of Earth Atmospheric and Environmental Sciences, University of Manchester, Oxford Road, Manchester, M13 9PL, UK.
authors.forename: Mohamed
authors.initials: M
authors.lastname: Ghalaieny
authors.forename: Asan
authors.initials: A
authors.lastname: Bacak
authors.forename: Max
authors.initials: M
authors.lastname: McGillen
authors.forename: Damien
authors.initials: D
authors.lastname: Martin
authors.forename: Alan V
authors.initials: AV
authors.lastname: Knights
authors.forename: Simon
authors.initials: S
authors.lastname: O'Doherty
authors.forename: Dudley E
authors.initials: DE
authors.lastname: Shallcross
authors.forename: Carl J
authors.initials: CJ
authors.lastname: Percival
mesh_terms: D001272:Atmosphere; D007700:Kinetics; D010126:Ozone / Q000737:chemistry*; D011312:Pressure; D012717:Sesquiterpenes / Q000737:chemistry*; D013696:Temperature
chemical_list: D012717:Sesquiterpenes; D010126:Ozone