Articles | Volume 2, issue 2
https://doi.org/10.5194/ar-2-303-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/ar-2-303-2024
© Author(s) 2024. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
27 Nov 2024
Research article |
| 27 Nov 2024
| 27 Nov 2024
Cluster-to-particle transition in atmospheric nanoclusters
Department of Chemistry, Aarhus University, Langelandsgade 140, 8000 Aarhus C, Denmark
Yosef Knattrup
Department of Chemistry, Aarhus University, Langelandsgade 140, 8000 Aarhus C, Denmark
Andreas Buchgraitz Jensen
Department of Chemistry, Aarhus University, Langelandsgade 140, 8000 Aarhus C, Denmark
Department of Chemistry, Aarhus University, Langelandsgade 140, 8000 Aarhus C, Denmark
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Aerosol formation is an important process for our global climate. However, there are large uncertainties associated with the formation of new aerosol particles. We present quantum chemical calculations of large atmospheric molecular cluster composed of sulfuric acid (SA), ammonia (AM) and dimethyl amine (DMA). We find that mixed SA-AM-DMA clusters more efficiently for freshly nucleated particles compared to the pure SA-AM and SA-DMA systems.
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Using quantum chemical methods we studied the uptake of first generation oxidation products onto freshly nucleated particles (FNPs). We find that pinic acid can condense on these small FNPs at realistic atmospheric conditions, thereby contributing to the early particle growth. The mechanism involves two pinic acid molecules interacting with each other, showing that direct organic-organic interactions during co-condensation onto the particle contributes to the growth.
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Aerosol formation is an important process for our global climate. However, there are large uncertainties associated with the formation of new aerosol particles. We present quantum chemical calculations of large atmospheric molecular cluster composed of sulfuric acid (SA), ammonia (AM) and dimethyl amine (DMA). We find that mixed SA-AM-DMA clusters more efficiently for freshly nucleated particles compared to the pure SA-AM and SA-DMA systems.
Astrid Nørskov Pedersen, Yosef Knattrup, and Jonas Elm
Aerosol Research, 2, 123–134, https://doi.org/10.5194/ar-2-123-2024, https://doi.org/10.5194/ar-2-123-2024, 2024
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Aerosol formation is an important process for our global climate. While inorganic species have been shown to be important for aerosol formation, there remains a large gap in our knowledge about the exact involvement of organics. We present a new quantum chemical procedure for screening relevant organics that for the first time allows us to obtain direct molecular-level insight into the organics involved in aerosol formation.
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Formic acid is screened out as the species that can effectively catalyze the new particle formation (NPF) of the methanesulfonic acid (MSA)–methylamine system, indicating organic acids might be required to facilitate MSA-driven NPF in the atmosphere. The results are significant to comprehensively understand the MSA-driven NPF and expand current knowledge of the contribution of OAs to NPF.
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Kasper Kristensen, Louise N. Jensen, Lauriane L. J. Quéléver, Sigurd Christiansen, Bernadette Rosati, Jonas Elm, Ricky Teiwes, Henrik B. Pedersen, Marianne Glasius, Mikael Ehn, and Merete Bilde
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Atmospheric particles are important in relation to human health and the global climate. As the global temperature changes, so may the atmospheric chemistry controlling the formation of particles from reactions of naturally emitted volatile organic compounds (VOCs). In the current work, we show how temperatures influence the formation and chemical composition of atmospheric particles from α-pinene: a biogenic VOC largely emitted in high-latitude environments such as the boreal forests.
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Short summary
The exact point at which a given assembly of molecules represents an atmospheric molecular cluster or a particle remains ambiguous. Using quantum chemical methods, here we explore a cluster-to-particle transition point. Based on our results, we deduce a property-based criterion for defining freshly nucleated particles (FNPs) that act as a boundary between discrete cluster configurations and bulk particles.
The exact point at which a given assembly of molecules represents an atmospheric molecular...
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