Biotechnology

Unimolecular reactions of anti-glycolaldehyde oxides and their reactions with


Criegee intermediate is produced in the ozonolysis of unsaturated compounds in the atmosphere. These intermediaries are very important because they contribute to the formation of nocturnal OH radicals and the formation of secondary organic aerosols. OH radicals increase the oxidative capacity of the atmosphere, and aerosols can reflect or absorb sunlight and contribute to cloud formation. The Criegee intermediate also plays an important role in the conversion of sulfur dioxide to sulfur trioxide, which ultimately results in the formation of sulfuric acid, which is toxic and has been identified as an important nucleating precursor in the acid rain mechanism. In addition, Criegee intermediates can be significant adsorbents for atmospheric acids and aldehydes. Therefore, we must understand the chemical kinetics of Criegee intermediates, but experimental information is difficult to obtain for these highly reactive intermediates and is limited. Therefore, theory can play an important role, especially if it is done at the highest possible level.

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Criegee intermediate is produced in the ozonolysis of unsaturated compounds in the atmosphere. These intermediaries are very important because they contribute to the formation of nocturnal OH radicals and the formation of secondary organic aerosols. OH radicals increase the oxidative capacity of the atmosphere, and aerosols can reflect or absorb sunlight and contribute to cloud formation. The Criegee intermediate also plays an important role in the conversion of sulfur dioxide to sulfur trioxide, which ultimately results in the formation of sulfuric acid, which is toxic and has been identified as an important nucleating precursor in the acid rain mechanism. In addition, Criegee intermediates can be significant adsorbents for atmospheric acids and aldehydes. Therefore, we must understand the chemical kinetics of Criegee intermediates, but experimental information is difficult to obtain for these highly reactive intermediates and is limited. Therefore, theory can play an important role, especially if it is done at the highest possible level.

Anti-glycoaldehyde oxide (e-(CH2OH)CHOO) is a substituted Criegee intermediate produced in the ozonolysis of unsaturated alcohols. In this article, high-order pairwise cluster theory and transition state theory of multiple-level multi-structure canonical variations with corner tunneling are used to investigate the unimolecular reactions of eCH2(OH)CHOO and the bimolecular reaction between this intermediate and water vapor in the atmosphere. The article found that the out-of-CCSD(T) contribution to the electronic structure (that is, the importance of highly correlated excitation) depends on the specific reaction. In addition, the reaction with the water monomer of the heterodimer of eCH2(OH)CHOO complexes with water molecules dominating the reaction eCH2(OH)CHOO with water dimer at low temperature; This reaction pathway, although not considered in the previous literature, is probably common in many Criegee intermediates thermomolecular reactions with two water molecules. This study also found that the OH substituent in the Criegee intermediate increased its reactivity.

These findings can guide the structure-activity relationships currently used to model atmospheric chemistry, and therefore can enhance our understanding of climate change and acid rain.




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