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Title: Mechanisms and competition of halide substitution and hydrolysis in reactions of N 2 O 5 with seawater
S N 2-type halide substitution and hydrolysis are two of the most ubiquitous reactions in chemistry. The interplay between these processes is fundamental in atmospheric chemistry through reactions of N 2 O 5 and seawater. N 2 O 5 plays a major role in regulating levels of O 3 , OH, NO x , and CH 4 . While the reactions of N 2 O 5 and seawater are of central importance, little is known about their mechanisms. Of interest is the activation of Cl in seawater by the formation of gaseous ClNO 2 , which occurs despite the fact that hydrolysis (to HNO 3 ) is energetically more favorable. We determine key features of the reaction landscape that account for this behavior in a theoretical study of the cluster N 2 O 5 /Cl − /H 2 O. This was carried out using ab initio molecular dynamics to determine reaction pathways, structures, and time scales. While hydrolysis of N 2 O 5 occurs in the absence of Cl − , results here reveal that a low-lying pathway featuring halide substitution intermediates enhances hydrolysis.  more » « less
Award ID(s):
1801971
PAR ID:
10096914
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
Science Advances
Volume:
5
Issue:
6
ISSN:
2375-2548
Page Range / eLocation ID:
eaav6503
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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