Open AccessTheoretical study on the ozonolysis of α-humulene in the atmosphere
Author(s) -
Jia’shuo Liu,
Guochun Lv,
Luyao Xu,
Danna Zhang,
Hengjun Peng,
Xiaomin Sun
Publication year - 2020
Publication title -
iop conference series. earth and environmental science
Language(s) - English
Resource type - Journals
eISSN - 1755-1307
pISSN - 1755-1315
DOI - 10.1088/1755-1315/510/4/042049
Subject(s) - ozonolysis , ozonide , humulene , chemistry , reaction rate constant , ozone , atmosphere (unit) , computational chemistry , photochemistry , organic chemistry , kinetics , thermodynamics , physics , chromatography , quantum mechanics , essential oil
α -Humulene is a major sesquiterpene which is produced by plants and can easily react with ozone in the atmosphere. The ozonolysis mechanism of α -humulene in the atmosphere was investigated by density functional theory and calculated rate constants using transition-state theory in this paper. In the ozonolysis of α -humulene, primary ozonides (POZ) are first formed after an addition reaction. Then, with the broken O-O bond, Criegee intermediates (CIs) are formed. The results discussed the subsequent reaction of CIs in detail, including the formation of secondary ozonide (SOZ) and the reaction of CIs with H 2 O. For the formation of SOZ, the path of SOZ6 is the best path in all six paths, with a low energy barrier (3.80 kcal mol −1 ) and high total rate constants (3.34 × 10 8 s −1 ) at 298 K and 1 atm. For the reaction of CIs with H 2 O, the production of P6 is the best path in all six paths, with a low energy barrier (9.87 kcal mol −1 ) and high total rate constants (9.58 × 10 −11 cm 3 molecule −1 s −1 ) at normal temperature and pressure. This work provides reaction mechanisms of the ozonolysis of α -humulene and finds the reliable paths in the subsequent reactions.