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Updated: May 13, 2026
Computation of Atmospheric Concentrations of Molecular Clusters from ab initio Thermochemistry
Published on: April 8, 2020
Reactions and reaction rate of atmospheric SO2 and O3(-) (H2O)n collisions via molecular dynamics simulations
Nicolai Bork1, Ville Loukonen, Hanna Vehkamäki
1Division of Atmospheric Sciences and Geophysics, Department of Physics, University of Helsinki, Finland. nicolai.bork@helsinki.fi
Abstract:
We present an ab initio study of gaseous SO(2) and O(3)(–)(H(2)O)(n) collisions. Opposed to the usual approach to determine reaction rates via structural optimizations and transition state theory, we successfully approach this problem using ab initio molecular dynamics. We demonstrate the advantages of this approach, being the automatic and unbiased inclusion of dynamic and steric effects as well as the simultaneous assessment of all possible reactions. For this particular system, we find that only one reaction will be of atmospheric significance. Further, we identify the main geometrical parameters governing and limiting the observed reaction and suggest a new measure of the reaction rate being ca. 3/4 of the collision rate.
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