Articles | Volume 25, issue 23
https://doi.org/10.5194/acp-25-17237-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/acp-25-17237-2025
© Author(s) 2025. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
01 Dec 2025
Research article |
| 01 Dec 2025
| 01 Dec 2025
Gas-phase collision rate enhancement factors for acid–base clusters up to 2 nm in diameter from atomistic simulation and the interacting hard-sphere model
Valtteri Tikkanen
CORRESPONDING AUTHOR
Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, P.O. Box 64, 00014, Helsinki, Finland
Huan Yang
Max Planck Institute for Chemistry, 55128 Mainz, Germany
Hanna Vehkamäki
Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, P.O. Box 64, 00014, Helsinki, Finland
Bernhard Reischl
Institute for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, P.O. Box 64, 00014, Helsinki, Finland
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Short summary
Collisions of neutral molecules and clusters comprise the prevalent pathway in atmospheric new particle formation. In heavily polluted urban areas, where clusters are formed rapidly and in large numbers, cluster–cluster collisions also become relevant. We calculate cluster–cluster collision rates from atomistic molecular dynamics simulations and an interacting hard-sphere model. Not accounting for long-range attractive interactions underestimates collision and particle formation rates significantly.
Collisions of neutral molecules and clusters comprise the prevalent pathway in atmospheric new...
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