| Title: | Molecular understanding of atmospheric particle formation from sulfuric acid and large oxidized organic molecules |
| Author(s): | Schobesberger S; Junninen H; Bianchi F; Lonn G; Ehn M; Lehtipalo K; Dommen J; Ehrhart S; Ortega IK; Franchin A; Nieminen T; Riccobono F; Hutterli M; Duplissy J; Almeida J; Amorim A; Breitenlechner M; Downard AJ; Dunne EM; Flagan RC; Kajos M; Keskinen H; Kirkby J; Kupc A; Kurten A; Kurten T; Laaksonen A; Mathot S; Onnela A; Praplan AP; Rondo L; Santos FD; Schallhart S; Schnitzhofer R; Sipila M; Tome A; Tsagkogeorgas G; Vehkamaki H; Wimmer D; Baltensperger U; Carslaw KS; Curtius J; Hansel A; Petaja T; Kulmala M; Donahue NM; Worsnop DR; |
| Address: | "Department of Physics, University of Helsinki, 00014 Helsinki, Finland" |
| ISSN/ISBN: | 1091-6490 (Electronic) 0027-8424 (Print) 0027-8424 (Linking) |
| Abstract: | "Atmospheric aerosols formed by nucleation of vapors affect radiative forcing and therefore climate. However, the underlying mechanisms of nucleation remain unclear, particularly the involvement of organic compounds. Here, we present high-resolution mass spectra of ion clusters observed during new particle formation experiments performed at the Cosmics Leaving Outdoor Droplets chamber at the European Organization for Nuclear Research. The experiments involved sulfuric acid vapor and different stabilizing species, including ammonia and dimethylamine, as well as oxidation products of pinanediol, a surrogate for organic vapors formed from monoterpenes. A striking resemblance is revealed between the mass spectra from the chamber experiments with oxidized organics and ambient data obtained during new particle formation events at the Hyytiala boreal forest research station. We observe that large oxidized organic compounds, arising from the oxidation of monoterpenes, cluster directly with single sulfuric acid molecules and then form growing clusters of one to three sulfuric acid molecules plus one to four oxidized organics. Most of these organic compounds retain 10 carbon atoms, and some of them are remarkably highly oxidized (oxygen-to-carbon ratios up to 1.2). The average degree of oxygenation of the organic compounds decreases while the clusters are growing. Our measurements therefore connect oxidized organics directly, and in detail, with the very first steps of new particle formation and their growth between 1 and 2 nm in a controlled environment. Thus, they confirm that oxidized organics are involved in both the formation and growth of particles under ambient conditions" |
| Keywords: | Aerosols/analysis/chemistry Ammonia/analysis/chemistry Atmosphere/analysis/*chemistry Dimethylamines/analysis/chemistry Environmental Monitoring/instrumentation/methods Mass Spectrometry Monoterpenes/*chemistry Organic Chemicals/analysis/*chemistry Oxidat; |
| Notes: | "MedlineSchobesberger, Siegfried Junninen, Heikki Bianchi, Federico Lonn, Gustaf Ehn, Mikael Lehtipalo, Katrianne Dommen, Josef Ehrhart, Sebastian Ortega, Ismael K Franchin, Alessandro Nieminen, Tuomo Riccobono, Francesco Hutterli, Manuel Duplissy, Jonathan Almeida, Joao Amorim, Antonio Breitenlechner, Martin Downard, Andrew J Dunne, Eimear M Flagan, Richard C Kajos, Maija Keskinen, Helmi Kirkby, Jasper Kupc, Agnieszka Kurten, Andreas Kurten, Theo Laaksonen, Ari Mathot, Serge Onnela, Antti Praplan, Arnaud P Rondo, Linda Santos, Filipe D Schallhart, Simon Schnitzhofer, Ralf Sipila, Mikko Tome, Antonio Tsagkogeorgas, Georgios Vehkamaki, Hanna Wimmer, Daniela Baltensperger, Urs Carslaw, Kenneth S Curtius, Joachim Hansel, Armin Petaja, Tuukka Kulmala, Markku Donahue, Neil M Worsnop, Douglas R eng 227463/ERC_/European Research Council/International Research Support, Non-U.S. Gov't Research Support, U.S. Gov't, Non-P.H.S. 2013/10/09 Proc Natl Acad Sci U S A. 2013 Oct 22; 110(43):17223-8. doi: 10.1073/pnas.1306973110. Epub 2013 Oct 7" |
