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Updated: Apr 1, 2026

Computation of Atmospheric Concentrations of Molecular Clusters from ab initio Thermochemistry
Published on: April 8, 2020
Role of (H2O)(n) (n = 2-3) Clusters on the HO2 + O3 Reaction: A Theoretical Study
Luís P Viegas1, António J C Varandas1
1Centro de Química and Departamento de Química, Universidade de Coimbra , 3004-535 Coimbra, Portugal.
Abstract:
We report a theoretical investigation on the role of the water dimer and trimer in the reaction between the hydroperoxyl radical and ozone. This study is part of an ongoing series of research endeavors that intend to deliver a comprehensive understanding on the role of water on this reaction. Due to the complexity of the potential energy surface, and to be able to make comparisons with our previous works, our calculations have employed model chemistries based on the Kohn-Sham DFT formalism. It is found that the calculated reaction paths share a common scheme, not only in the context of this work, but also in consideration of our previous studies. Also, oxygen-abstraction barriers are always submerged, with the relative energy between the hydrogen- and oxygen-abstraction saddle-points increasing with the number of water molecules, which maintain an apparent spectator role. Finally, we report novel HO2···(H2O)3 and HO3···(H2O)n complexes originating from our reaction schemes.
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