TY  - JOUR
A1  - Kürten, Christoph Andreas
A1  - Münch, S.
A1  - Rondo, Linda
A1  - Bianchi, Federico
A1  - Duplissy, Jonathan
A1  - Jokinen, Tuija
A1  - Junninen, Heikki
A1  - Sarnela, Nina
A1  - Schobesberger, Siegfried
A1  - Simon, Mario
A1  - Sipilä, Mikko
A1  - Almeida, Joao
A1  - Amorim, Antonio
A1  - Dommen, Josef
A1  - Donahue, Neil McPherson
A1  - Dunne, Eimear M.
A1  - Flagan, Richard C.
A1  - Franchin, Alessandro
A1  - Kirkby, Jasper
A1  - Kupc, Agnieszka
A1  - Makhmutov, Vladimir
A1  - Petäjä, Tuukka
A1  - Praplan, Arnaud Patrick
A1  - Riccobono, Francesco
A1  - Steiner, Gerhard
A1  - Tomé, Antonio
A1  - Tsagkogeorgas, Georgios
A1  - Wagner, Paul E.
A1  - Wimmer, Daniela
A1  - Baltensperger, Urs
A1  - Kulmala, Markku
A1  - Worsnop, Douglas R.
A1  - Curtius, Joachim
T1  - Thermodynamics of the formation of sulfuric acid dimers in the binary (H2SO4–H2O) and ternary (H2SO4–H2O–NH3) system
T2  - Atmospheric chemistry and physics
N2  - Sulfuric acid is an important gas influencing atmospheric new particle formation (NPF). Both the binary (H2SO4–H2O) system and the ternary system involving ammonia (H2SO4–H2O–NH3) may be important in the free troposphere. An essential step in the nucleation of aerosol particles from gas-phase precursors is the formation of a dimer, so an understanding of the thermodynamics of dimer formation over a wide range of atmospheric conditions is essential to describe NPF. We have used the CLOUD chamber to conduct nucleation experiments for these systems at temperatures from 208 to 248 K. Neutral monomer and dimer concentrations of sulfuric acid were measured using a chemical ionization mass spectrometer (CIMS). From these measurements, dimer evaporation rates in the binary system were derived for temperatures of 208 and 223 K. We compare these results to literature data from a previous study that was conducted at higher temperatures but is in good agreement with the present study. For the ternary system the formation of H2SO4·NH3 is very likely an essential step in the formation of sulfuric acid dimers, which were measured at 210, 223, and 248 K. We estimate the thermodynamic properties (dH and dS) of the H2SO4·NH3 cluster using a simple heuristic model and the measured data. Furthermore, we report the first measurements of large neutral sulfuric acid clusters containing as many as 10 sulfuric acid molecules for the binary system using chemical ionization–atmospheric pressure interface time-of-flight (CI-APi-TOF) mass spectrometry.
Y1  - 2015
UR  - http://publikationen.ub.uni-frankfurt.de/frontdoor/index/index/docId/39525
UR  - https://nbn-resolving.org/urn:nbn:de:hebis:30:3-395253
SN  - 1680-7324
N1  - © Author(s) 2015. CC Attribution 3.0 License.
VL  - 15
SP  - 10701
EP  - 10721
PB  - European Geosciences Union
CY  - Katlenburg-Lindau
ER  -