AI Article Synopsis
- Ozonation of alkenes, particularly 2-methyl-1-butene (2M1B) and 2-methyl-2-butene (2M2B), is crucial for the formation of secondary organic aerosols (SOA) in the atmosphere.
- Low-temperature matrix isolation techniques were used to identify key intermediates such as Primary ozonides (POZs), Criegee Intermediates (CIs), and Secondary ozonides (SOZs), revealing the complexity of reactions based on the structure of the alkenes.
- The study discovered that asymmetric alkenes produce diverse CIs and SOZs during ozonation, with significant amounts of formaldehyde (HCHO) and other
Article Abstract
O and alkenes are important reactants in the formation of SOA in the atmosphere. The intermediates and reaction mechanism of ozonation of alkene is an important topic in atmospheric chemistry. In this study, the low-temperature matrix isolation was used to capture the intermediates such as Primary ozonides (POZs), Criegee Intermediates (CIs), and Secondary ozonides (SOZs) generated from ozonation of 2-methyl-1-butene (2M1B) and 2-methyl-2-butene (2M2B). The results have been identified by the vacuum infrared spectroscopy and theoretical calculation. Our results show that during the ozonation of asymmetric alkenes, two kinds of CIs and more than two kinds of SOZs were generated due to the different decomposition modes of POZs. The infrared absorption peaks of (CH)COO and CHCHC(CH)OO for O-O telescopic vibration was determined to be 889 cm and 913 cm, respectively. Using the merged jet method, it was found that a large amount of HCHO was produced during the ozonation of 2M1B, and glyoxal and methylglyoxal were produced in the ozonation of 2M2B. Our findings highlight the importance of asymmetric alkene ozonolysis reactions in producing CIs, further improving the understanding of the generation of CIs from ozonation of alkenes.
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| http://dx.doi.org/10.1016/j.chemosphere.2020.126413 | DOI Listing |
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