Kinetics and mechanisms of gas phase reactions of hexenols with ozone

• Published in: RSC advances Vol. 6; no. 87; pp. 83573 - 83580
• Main Authors: Lin, Xiaoxiao, Ma, Qiao, Yang, Chengqiang, Tang, Xiaofeng, Zhao, Weixiong, Hu, Changjin, Gu, Xuejun, Fang, Bo, Gai, Yanbo, Zhang, Weijun
• Format: Journal Article
• Language: English
• Published: 01.01.2016
• Subjects: Atmospheric pressure; Barometric pressure; Density functional theory; Gain; Mathematical analysis; Radicals; Rate constants; Reaction kinetics
• ISSN: 2046-2069; 2046-2069
• DOI: 10.1039/C6RA17107A

An absolute kinetic study is reported for the reactions of O 3 with a series of C6 hexenols, ( Z )-2-hexen-1-ol, ( Z )-3-hexen-1-ol, ( Z )-4-hexen-1-ol, ( E )-2-hexen-1-ol, ( E )-3-hexen-1-ol, and ( E )-4-hexen-1-ol. At 298 K and atmospheric pressure, the rate constants (in units of 10 −17 cm 3 molecule −1 s −1 ) were measured to be 7.44 ± 1.03, 5.47 ± 0.71, 7.09 ± 0.91, 16.6 ± 2.2, 6.19 ± 0.72 and 10.5 ± 1.4, respectively. To gain a deeper insight into the reactivity and mechanism, theoretical calculations were also performed for the title reactions with the methods of density functional theory (DFT) and transition-state theory (TST). The geometries, energies, and harmonic vibrational frequencies of each stationary point were obtained at the BH&HLYP/6-31+G(d,p) level of theory. The calculated rate constants are in good agreement with the experimental data, and the reactivity of hexenols with O 3 shows a strong dependence on their chemical structure based on the theoretical results. Finally, lifetimes of the C6 hexenols, with respect to their reactions with some important atmospheric oxidants such as O 3 , OH and NO 3 radicals, have also been discussed in the article.