Influence of temperature on the molecular composition of ions and charged clusters during pure biogenic nucleation
It was recently shown by the CERN CLOUD experiment that biogenic highly oxygenated molecules (HOMs) form particles under atmospheric conditions in the absence of sulfuric acid, where ions enhance the nucleation rate by 1–2 orders of magnitude. The biogenic HOMs were produced from ozonoly...
| Main Authors: | , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Copernicus Publications
2018-01-01
|
| Series: | Atmospheric Chemistry and Physics |
| Online Access: | https://www.atmos-chem-phys.net/18/65/2018/acp-18-65-2018.pdf |
| id |
doaj-d748ca897f3e41cdb5e17b9c28f207cd |
|---|---|
| record_format |
Article |
| collection |
DOAJ |
| language |
English |
| format |
Article |
| sources |
DOAJ |
| author |
C. Frege I. K. Ortega M. P. Rissanen A. P. Praplan G. Steiner G. Steiner G. Steiner M. Heinritzi L. Ahonen A. Amorim A.-K. Bernhammer A.-K. Bernhammer F. Bianchi F. Bianchi S. Brilke S. Brilke S. Brilke M. Breitenlechner M. Breitenlechner L. Dada A. Dias J. Duplissy J. Duplissy S. Ehrhart S. Ehrhart I. El-Haddad L. Fischer C. Fuchs O. Garmash M. Gonin A. Hansel A. Hansel C. R. Hoyle T. Jokinen H. Junninen H. Junninen J. Kirkby J. Kirkby A. Kürten K. Lehtipalo K. Lehtipalo M. Leiminger M. Leiminger R. L. Mauldin R. L. Mauldin U. Molteni L. Nichman T. Petäjä N. Sarnela S. Schobesberger S. Schobesberger M. Simon M. Sipilä D. Stolzenburg A. Tomé A. L. Vogel A. L. Vogel A. C. Wagner R. Wagner M. Xiao C. Yan P. Ye P. Ye J. Curtius N. M. Donahue R. C. Flagan M. Kulmala D. R. Worsnop D. R. Worsnop D. R. Worsnop P. M. Winkler J. Dommen U. Baltensperger |
| spellingShingle |
C. Frege I. K. Ortega M. P. Rissanen A. P. Praplan G. Steiner G. Steiner G. Steiner M. Heinritzi L. Ahonen A. Amorim A.-K. Bernhammer A.-K. Bernhammer F. Bianchi F. Bianchi S. Brilke S. Brilke S. Brilke M. Breitenlechner M. Breitenlechner L. Dada A. Dias J. Duplissy J. Duplissy S. Ehrhart S. Ehrhart I. El-Haddad L. Fischer C. Fuchs O. Garmash M. Gonin A. Hansel A. Hansel C. R. Hoyle T. Jokinen H. Junninen H. Junninen J. Kirkby J. Kirkby A. Kürten K. Lehtipalo K. Lehtipalo M. Leiminger M. Leiminger R. L. Mauldin R. L. Mauldin U. Molteni L. Nichman T. Petäjä N. Sarnela S. Schobesberger S. Schobesberger M. Simon M. Sipilä D. Stolzenburg A. Tomé A. L. Vogel A. L. Vogel A. C. Wagner R. Wagner M. Xiao C. Yan P. Ye P. Ye J. Curtius N. M. Donahue R. C. Flagan M. Kulmala D. R. Worsnop D. R. Worsnop D. R. Worsnop P. M. Winkler J. Dommen U. Baltensperger Influence of temperature on the molecular composition of ions and charged clusters during pure biogenic nucleation Atmospheric Chemistry and Physics |
| author_facet |
C. Frege I. K. Ortega M. P. Rissanen A. P. Praplan G. Steiner G. Steiner G. Steiner M. Heinritzi L. Ahonen A. Amorim A.-K. Bernhammer A.-K. Bernhammer F. Bianchi F. Bianchi S. Brilke S. Brilke S. Brilke M. Breitenlechner M. Breitenlechner L. Dada A. Dias J. Duplissy J. Duplissy S. Ehrhart S. Ehrhart I. El-Haddad L. Fischer C. Fuchs O. Garmash M. Gonin A. Hansel A. Hansel C. R. Hoyle T. Jokinen H. Junninen H. Junninen J. Kirkby J. Kirkby A. Kürten K. Lehtipalo K. Lehtipalo M. Leiminger M. Leiminger R. L. Mauldin R. L. Mauldin U. Molteni L. Nichman T. Petäjä N. Sarnela S. Schobesberger S. Schobesberger M. Simon M. Sipilä D. Stolzenburg A. Tomé A. L. Vogel A. L. Vogel A. C. Wagner R. Wagner M. Xiao C. Yan P. Ye P. Ye J. Curtius N. M. Donahue R. C. Flagan M. Kulmala D. R. Worsnop D. R. Worsnop D. R. Worsnop P. M. Winkler J. Dommen U. Baltensperger |
| author_sort |
C. Frege |
| title |
Influence of temperature on the molecular composition of ions and charged clusters during pure biogenic nucleation |
| title_short |
Influence of temperature on the molecular composition of ions and charged clusters during pure biogenic nucleation |
| title_full |
Influence of temperature on the molecular composition of ions and charged clusters during pure biogenic nucleation |
| title_fullStr |
Influence of temperature on the molecular composition of ions and charged clusters during pure biogenic nucleation |
| title_full_unstemmed |
Influence of temperature on the molecular composition of ions and charged clusters during pure biogenic nucleation |
| title_sort |
influence of temperature on the molecular composition of ions and charged clusters during pure biogenic nucleation |
| publisher |
Copernicus Publications |
| series |
Atmospheric Chemistry and Physics |
| issn |
1680-7316 1680-7324 |
| publishDate |
2018-01-01 |
| description |
It was recently shown by the CERN CLOUD experiment that biogenic highly
oxygenated molecules (HOMs) form particles under atmospheric conditions in
the absence of sulfuric acid, where ions enhance the nucleation rate by 1–2 orders of magnitude. The biogenic HOMs were produced from ozonolysis of <i>α</i>-pinene at 5 °C. Here we extend this study to compare the
molecular composition of positive and negative HOM clusters measured with
atmospheric pressure interface time-of-flight mass spectrometers (APi-TOFs),
at three different temperatures (25, 5 and −25 °C). Most negative HOM clusters include a nitrate (NO<sub>3</sub><sup>−</sup>) ion, and the spectra are similar to those seen in the nighttime boreal forest. On the other hand, most positive HOM clusters include an ammonium (NH<sub>4</sub><sup>+</sup>) ion, and the spectra are characterized by mass bands that differ in their molecular weight by ∼ 20 C atoms, corresponding to HOM dimers. At lower temperatures the average oxygen to carbon (O : C) ratio of the HOM clusters decreases for both polarities, reflecting an overall reduction of HOM formation with decreasing temperature. This indicates a decrease in the rate of autoxidation with temperature due to a rather high activation energy as has previously been determined by quantum chemical calculations. Furthermore, at the lowest temperature (−25 °C), the presence of C<sub>30</sub> clusters shows that HOM monomers start to contribute to the nucleation of positive clusters. These experimental findings are supported by quantum chemical calculations of the binding energies of representative neutral and charged clusters. |
| url |
https://www.atmos-chem-phys.net/18/65/2018/acp-18-65-2018.pdf |
| work_keys_str_mv |
AT cfrege influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT ikortega influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT mprissanen influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT appraplan influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT gsteiner influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT gsteiner influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT gsteiner influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT mheinritzi influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT lahonen influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT aamorim influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT akbernhammer influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT akbernhammer influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT fbianchi influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT fbianchi influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT sbrilke influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT sbrilke influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT sbrilke influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT mbreitenlechner influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT mbreitenlechner influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT ldada influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT adias influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT jduplissy influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT jduplissy influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT sehrhart influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT sehrhart influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT ielhaddad influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT lfischer influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT cfuchs influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT ogarmash influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT mgonin influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT ahansel influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT ahansel influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT crhoyle influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT tjokinen influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT hjunninen influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT hjunninen influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT jkirkby influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT jkirkby influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT akurten influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT klehtipalo influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT klehtipalo influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT mleiminger influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT mleiminger influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT rlmauldin influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT rlmauldin influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT umolteni influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT lnichman influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT tpetaja influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT nsarnela influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT sschobesberger influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT sschobesberger influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT msimon influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT msipila influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT dstolzenburg influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT atome influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT alvogel influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT alvogel influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT acwagner influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT rwagner influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT mxiao influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT cyan influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT pye influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT pye influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT jcurtius influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT nmdonahue influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT rcflagan influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT mkulmala influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT drworsnop influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT drworsnop influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT drworsnop influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT pmwinkler influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT jdommen influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation AT ubaltensperger influenceoftemperatureonthemolecularcompositionofionsandchargedclustersduringpurebiogenicnucleation |
| _version_ |
1725455736826232832 |
| spelling |
doaj-d748ca897f3e41cdb5e17b9c28f207cd2020-11-24T23:57:04ZengCopernicus PublicationsAtmospheric Chemistry and Physics1680-73161680-73242018-01-0118657910.5194/acp-18-65-2018Influence of temperature on the molecular composition of ions and charged clusters during pure biogenic nucleationC. Frege0I. K. Ortega1M. P. Rissanen2A. P. Praplan3G. Steiner4G. Steiner5G. Steiner6M. Heinritzi7L. Ahonen8A. Amorim9A.-K. Bernhammer10A.-K. Bernhammer11F. Bianchi12F. Bianchi13S. Brilke14S. Brilke15S. Brilke16M. Breitenlechner17M. Breitenlechner18L. Dada19A. Dias20J. Duplissy21J. Duplissy22S. Ehrhart23S. Ehrhart24I. El-Haddad25L. Fischer26C. Fuchs27O. Garmash28M. Gonin29A. Hansel30A. Hansel31C. R. Hoyle32T. Jokinen33H. Junninen34H. Junninen35J. Kirkby36J. Kirkby37A. Kürten38K. Lehtipalo39K. Lehtipalo40M. Leiminger41M. Leiminger42R. L. Mauldin43R. L. Mauldin44U. Molteni45L. Nichman46T. Petäjä47N. Sarnela48S. Schobesberger49S. Schobesberger50M. Simon51M. Sipilä52D. Stolzenburg53A. Tomé54A. L. Vogel55A. L. Vogel56A. C. Wagner57R. Wagner58M. Xiao59C. Yan60P. Ye61P. Ye62J. Curtius63N. M. Donahue64R. C. Flagan65M. Kulmala66D. R. Worsnop67D. R. Worsnop68D. R. Worsnop69P. M. Winkler70J. Dommen71U. Baltensperger72Paul Scherrer Institute, Laboratory of Atmospheric Chemistry, 5232 Villigen, SwitzerlandONERA – The French Aerospace Lab, 91123 Palaiseau, FranceUniversity of Helsinki, Department of Physics, P.O. Box 64, University of Helsinki, 00014 Helsinki, FinlandUniversity of Helsinki, Department of Physics, P.O. Box 64, University of Helsinki, 00014 Helsinki, FinlandUniversity of Helsinki, Department of Physics, P.O. Box 64, University of Helsinki, 00014 Helsinki, FinlandUniversity of Innsbruck, Institute of Ion Physics and Applied Physics, Technikerstraße 25, 6020 Innsbruck, AustriaUniversity of Vienna, Faculty of Physics, Boltzmanngasse 5, 1090 Vienna, AustriaInstitute for Atmospheric and Environmental Sciences, Goethe University Frankfurt, 60438 Frankfurt am Main, GermanyUniversity of Helsinki, Department of Physics, P.O. Box 64, University of Helsinki, 00014 Helsinki, FinlandUniversidade de Lisboa, Ed. C8, Campo Grande, 1749-016 Lisbon, PortugalUniversity of Innsbruck, Institute of Ion Physics and Applied Physics, Technikerstraße 25, 6020 Innsbruck, AustriaIonicon Analytik GmbH, Eduard-Bodem Gasse 3, 6020 Innsbruck, AustriaPaul Scherrer Institute, Laboratory of Atmospheric Chemistry, 5232 Villigen, SwitzerlandUniversity of Helsinki, Department of Physics, P.O. Box 64, University of Helsinki, 00014 Helsinki, FinlandUniversity of Innsbruck, Institute of Ion Physics and Applied Physics, Technikerstraße 25, 6020 Innsbruck, AustriaUniversity of Vienna, Faculty of Physics, Boltzmanngasse 5, 1090 Vienna, AustriaInstitute for Atmospheric and Environmental Sciences, Goethe University Frankfurt, 60438 Frankfurt am Main, GermanyUniversity of Innsbruck, Institute of Ion Physics and Applied Physics, Technikerstraße 25, 6020 Innsbruck, Austrianow at: Harvard University, School of Engineering and Applied Sciences, Cambridge, MA 02138, USAUniversity of Helsinki, Department of Physics, P.O. Box 64, University of Helsinki, 00014 Helsinki, FinlandUniversidade de Lisboa, Ed. C8, Campo Grande, 1749-016 Lisbon, PortugalUniversity of Helsinki, Department of Physics, P.O. Box 64, University of Helsinki, 00014 Helsinki, FinlandCERN, Geneva, SwitzerlandCERN, Geneva, Switzerlandnow at: Max-Planck Institute of Chemistry, Atmospheric Chemistry Department, 55128 Mainz, GermanyPaul Scherrer Institute, Laboratory of Atmospheric Chemistry, 5232 Villigen, SwitzerlandUniversity of Innsbruck, Institute of Ion Physics and Applied Physics, Technikerstraße 25, 6020 Innsbruck, AustriaPaul Scherrer Institute, Laboratory of Atmospheric Chemistry, 5232 Villigen, SwitzerlandUniversity of Helsinki, Department of Physics, P.O. Box 64, University of Helsinki, 00014 Helsinki, FinlandTofwerk AG, 3600 Thun, SwitzerlandUniversity of Innsbruck, Institute of Ion Physics and Applied Physics, Technikerstraße 25, 6020 Innsbruck, AustriaIonicon Analytik GmbH, Eduard-Bodem Gasse 3, 6020 Innsbruck, AustriaPaul Scherrer Institute, Laboratory of Atmospheric Chemistry, 5232 Villigen, SwitzerlandUniversity of Helsinki, Department of Physics, P.O. Box 64, University of Helsinki, 00014 Helsinki, FinlandUniversity of Helsinki, Department of Physics, P.O. Box 64, University of Helsinki, 00014 Helsinki, FinlandUniversity of Tartu, Institute of Physics, 50090 Tartu, EstoniaInstitute for Atmospheric and Environmental Sciences, Goethe University Frankfurt, 60438 Frankfurt am Main, GermanyCERN, Geneva, SwitzerlandInstitute for Atmospheric and Environmental Sciences, Goethe University Frankfurt, 60438 Frankfurt am Main, GermanyPaul Scherrer Institute, Laboratory of Atmospheric Chemistry, 5232 Villigen, SwitzerlandUniversity of Helsinki, Department of Physics, P.O. Box 64, University of Helsinki, 00014 Helsinki, FinlandUniversity of Innsbruck, Institute of Ion Physics and Applied Physics, Technikerstraße 25, 6020 Innsbruck, AustriaInstitute for Atmospheric and Environmental Sciences, Goethe University Frankfurt, 60438 Frankfurt am Main, GermanyUniversity of Helsinki, Department of Physics, P.O. Box 64, University of Helsinki, 00014 Helsinki, FinlandDepartment of Atmospheric and Oceanic Sciences, University of Colorado, Boulder, Colorado, 80309-0311, USAPaul Scherrer Institute, Laboratory of Atmospheric Chemistry, 5232 Villigen, SwitzerlandSchool of Earth and Environmental Sciences, University of Manchester, Manchester, M13 9PL, UKUniversity of Helsinki, Department of Physics, P.O. Box 64, University of Helsinki, 00014 Helsinki, FinlandUniversity of Helsinki, Department of Physics, P.O. Box 64, University of Helsinki, 00014 Helsinki, FinlandUniversity of Helsinki, Department of Physics, P.O. Box 64, University of Helsinki, 00014 Helsinki, FinlandUniversity of Eastern Finland, Department of Applied Physics, 70211 Kuopio, FinlandInstitute for Atmospheric and Environmental Sciences, Goethe University Frankfurt, 60438 Frankfurt am Main, GermanyUniversity of Helsinki, Department of Physics, P.O. Box 64, University of Helsinki, 00014 Helsinki, FinlandUniversity of Vienna, Faculty of Physics, Boltzmanngasse 5, 1090 Vienna, AustriaIDL – Universidade da Beira Interior, Av. Marquês D'Avila e Bolama, 6201-001 Covilhã, PortugalPaul Scherrer Institute, Laboratory of Atmospheric Chemistry, 5232 Villigen, SwitzerlandCERN, Geneva, SwitzerlandInstitute for Atmospheric and Environmental Sciences, Goethe University Frankfurt, 60438 Frankfurt am Main, GermanyUniversity of Helsinki, Department of Physics, P.O. Box 64, University of Helsinki, 00014 Helsinki, FinlandPaul Scherrer Institute, Laboratory of Atmospheric Chemistry, 5232 Villigen, SwitzerlandUniversity of Helsinki, Department of Physics, P.O. Box 64, University of Helsinki, 00014 Helsinki, FinlandCenter for Atmospheric Particle Studies, Carnegie Mellon University, Pittsburgh, Pennsylvania, 15213, USAAerodyne Research Inc., Billerica, Massachusetts, 01821, USAUniversity of Innsbruck, Institute of Ion Physics and Applied Physics, Technikerstraße 25, 6020 Innsbruck, AustriaCenter for Atmospheric Particle Studies, Carnegie Mellon University, Pittsburgh, Pennsylvania, 15213, USADivision of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California, 91125, USAUniversity of Helsinki, Department of Physics, P.O. Box 64, University of Helsinki, 00014 Helsinki, FinlandUniversity of Helsinki, Department of Physics, P.O. Box 64, University of Helsinki, 00014 Helsinki, FinlandUniversity of Eastern Finland, Department of Applied Physics, 70211 Kuopio, FinlandAerodyne Research Inc., Billerica, Massachusetts, 01821, USAUniversity of Vienna, Faculty of Physics, Boltzmanngasse 5, 1090 Vienna, AustriaPaul Scherrer Institute, Laboratory of Atmospheric Chemistry, 5232 Villigen, SwitzerlandPaul Scherrer Institute, Laboratory of Atmospheric Chemistry, 5232 Villigen, SwitzerlandIt was recently shown by the CERN CLOUD experiment that biogenic highly oxygenated molecules (HOMs) form particles under atmospheric conditions in the absence of sulfuric acid, where ions enhance the nucleation rate by 1–2 orders of magnitude. The biogenic HOMs were produced from ozonolysis of <i>α</i>-pinene at 5 °C. Here we extend this study to compare the molecular composition of positive and negative HOM clusters measured with atmospheric pressure interface time-of-flight mass spectrometers (APi-TOFs), at three different temperatures (25, 5 and −25 °C). Most negative HOM clusters include a nitrate (NO<sub>3</sub><sup>−</sup>) ion, and the spectra are similar to those seen in the nighttime boreal forest. On the other hand, most positive HOM clusters include an ammonium (NH<sub>4</sub><sup>+</sup>) ion, and the spectra are characterized by mass bands that differ in their molecular weight by ∼ 20 C atoms, corresponding to HOM dimers. At lower temperatures the average oxygen to carbon (O : C) ratio of the HOM clusters decreases for both polarities, reflecting an overall reduction of HOM formation with decreasing temperature. This indicates a decrease in the rate of autoxidation with temperature due to a rather high activation energy as has previously been determined by quantum chemical calculations. Furthermore, at the lowest temperature (−25 °C), the presence of C<sub>30</sub> clusters shows that HOM monomers start to contribute to the nucleation of positive clusters. These experimental findings are supported by quantum chemical calculations of the binding energies of representative neutral and charged clusters.https://www.atmos-chem-phys.net/18/65/2018/acp-18-65-2018.pdf |