Determination of gas-phase ozonolysis rate coefficients of a number of sesquiterpenes at elevated temperatures using the relative rate method

Ghalaieny M., Bacak A., McGillen M., Martin D., Knights A. V., O'Doherty S., ...More

PHYSICAL CHEMISTRY CHEMICAL PHYSICS, vol.14, no.18, pp.6596-6602, 2012 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 14 Issue: 18
  • Publication Date: 2012
  • Doi Number: 10.1039/c2cp23988d
  • Journal Name: PHYSICAL CHEMISTRY CHEMICAL PHYSICS
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.6596-6602
  • Ankara University Affiliated: No

Abstract

The rates of ozonolysis of four sesquiterpenes, beta-caryophyllene, alpha-humulene, isolongifolene and alpha-cedrene, are determined in the gas phase at an elevated temperature of 366 +/- 3 K and a pressure of similar to 780 Torr using the EXTreme RAnge chamber (EXTRA). The experimentally obtained rate coefficients agree with extrapolated room temperature rate coefficients for isolongifolene and alpha-cedrene but not for beta-caryophyllene and alpha-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.