PHYS 327 |
| Andrew Borisovich Ryzhkov and Parisa Ariya. Department of Atmospheric and Oceanic Sciences, and Chemistry, McGill University, 805 Sherbrooke Street West, Montreal, QC H3A 2K6, Canada |
| Carbonyl oxide (Criegee intermediate) is a well-known intermediate formed in gas-phase reactions of ozone with alkenes. Secondary reactions of carbonyl oxide are suggested to lead to the formation of HO, H2O2 and organic peroxides in the atmosphere. So, study of details of the reactions is very important for understanding of the atmospheric pollutants destruction mechanism. We performed a theoretical study of reactions of a series of carbonyl oxides with water and a water dimer at CCSD(T)/6-311+G(2d,2p)//B3LYP/6-311+G(2d,2p) level. In this paper we discuss the several reaction pathways, namely formation of hydroxymethyl hydroperoxide, formaldehyde and hydrogen peroxide, and hydrogen trioxide. Also we evaluate the importance of these channels in the chemistry of the atmosphere. We found that the most energetically favourable channel is the formation of hydroxymethyl hydroperoxide (HMHP) as the result of reactions of carbonyl oxide with the water dimer preceeded by a hydrogen-bond complexation between Criegee intermediate and water dimer. The potential importance of water dimer reactions in the chemistry of the troposphere is discussed herein. |
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Physical Chemistry Poster Session
7:30 PM-10:00 PM, Wednesday, March 26, 2003 Convention Center -- Hall J, Poster
Division of Physical Chemistry |