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Stropoli SJ, Khuu T, Boyer MA, Karimova NV, Gavin-Hanner CF, Mitra S, Lachowicz AL, Yang N, Gerber RB, McCoy AB, Johnson MA. Electronic and mechanical anharmonicities in the vibrational spectra of the H-bonded, cryogenically cooled X - · HOCl (X=Cl, Br, I) complexes: Characterization of the strong anionic H-bond to an acidic OH group. J Chem Phys 2022; 156:174303. [PMID: 35525657 DOI: 10.1063/5.0083078] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We report vibrational spectra of the H2-tagged, cryogenically cooled X- · HOCl (X = Cl, Br, and I) ion-molecule complexes and analyze the resulting band patterns with electronic structure calculations and an anharmonic theoretical treatment of nuclear motions on extended potential energy surfaces. The complexes are formed by "ligand exchange" reactions of X- · (H2O)n clusters with HOCl molecules at low pressure (∼10-2 mbar) in a radio frequency ion guide. The spectra generally feature many bands in addition to the fundamentals expected at the double harmonic level. These "extra bands" appear in patterns that are similar to those displayed by the X- · HOD analogs, where they are assigned to excitations of nominally IR forbidden overtones and combination bands. The interactions driving these features include mechanical and electronic anharmonicities. Particularly intense bands are observed for the v = 0 → 2 transitions of the out-of-plane bending soft modes of the HOCl molecule relative to the ions. These involve displacements that act to break the strong H-bond to the ion, which give rise to large quadratic dependences of the electric dipoles (electronic anharmonicities) that drive the transition moments for the overtone bands. On the other hand, overtone bands arising from the intramolecular OH bending modes of HOCl are traced to mechanical anharmonic coupling with the v = 1 level of the OH stretch (Fermi resonances). These interactions are similar in strength to those reported earlier for the X- · HOD complexes.
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Affiliation(s)
- Santino J Stropoli
- Sterling Chemistry Laboratory, Department of Chemistry, Yale University, New Haven, Connecticut 06520, USA
| | - Thien Khuu
- Sterling Chemistry Laboratory, Department of Chemistry, Yale University, New Haven, Connecticut 06520, USA
| | - Mark A Boyer
- Department of Chemistry, University of Washington, Seattle, Washington 98195, USA
| | - Natalia V Karimova
- Department of Chemistry, University of California Irvine, Irvine, California 92697, USA
| | - Coire F Gavin-Hanner
- Department of Chemistry, University of Washington, Seattle, Washington 98195, USA
| | - Sayoni Mitra
- Sterling Chemistry Laboratory, Department of Chemistry, Yale University, New Haven, Connecticut 06520, USA
| | - Anton L Lachowicz
- Sterling Chemistry Laboratory, Department of Chemistry, Yale University, New Haven, Connecticut 06520, USA
| | - Nan Yang
- Sterling Chemistry Laboratory, Department of Chemistry, Yale University, New Haven, Connecticut 06520, USA
| | - R Benny Gerber
- Department of Chemistry, University of California Irvine, Irvine, California 92697, USA
| | - Anne B McCoy
- Department of Chemistry, University of Washington, Seattle, Washington 98195, USA
| | - Mark A Johnson
- Sterling Chemistry Laboratory, Department of Chemistry, Yale University, New Haven, Connecticut 06520, USA
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Marelle L, Thomas JL, Ahmed S, Tuite K, Stutz J, Dommergue A, Simpson WR, Frey MM, Baladima F. Implementation and Impacts of Surface and Blowing Snow Sources of Arctic Bromine Activation Within WRF-Chem 4.1.1. JOURNAL OF ADVANCES IN MODELING EARTH SYSTEMS 2021; 13:e2020MS002391. [PMID: 34434492 PMCID: PMC8365729 DOI: 10.1029/2020ms002391] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 06/08/2021] [Accepted: 06/16/2021] [Indexed: 05/27/2023]
Abstract
Elevated concentrations of atmospheric bromine are known to cause ozone depletion in the Arctic, which is most frequently observed during springtime. We implement a detailed description of bromine and chlorine chemistry within the WRF-Chem 4.1.1 model, and two different descriptions of Arctic bromine activation: (1) heterogeneous chemistry on surface snow on sea ice, triggered by ozone deposition to snow (Toyota et al., 2011 https://doi.org/10.5194/acp-11-3949-2011), and (2) heterogeneous reactions on sea salt aerosols emitted through the sublimation of lofted blowing snow (Yang et al., 2008, https://doi.org/10.1029/2008gl034536). In both mechanisms, bromine activation is sustained by heterogeneous reactions on aerosols and surface snow. Simulations for spring 2012 covering the entire Arctic reproduce frequent and widespread ozone depletion events, and comparisons with observations of ozone show that these developments significantly improve model predictions during the Arctic spring. Simulations show that ozone depletion events can be initiated by both surface snow on sea ice, or by aerosols that originate from blowing snow. On a regional scale, in spring 2012, snow on sea ice dominates halogen activation and ozone depletion at the surface. During this period, blowing snow is a major source of Arctic sea salt aerosols but only triggers a few depletion events.
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Affiliation(s)
- Louis Marelle
- Institut des Géosciences de l'Environnement, de l'Université Grenoble Alpes, CNRS, IRD, Grenoble INPGrenobleFrance
- LATMOS/IPSLSorbonne UniversitéUVSQCNRSParisFrance
| | - Jennie L. Thomas
- Institut des Géosciences de l'Environnement, de l'Université Grenoble Alpes, CNRS, IRD, Grenoble INPGrenobleFrance
- LATMOS/IPSLSorbonne UniversitéUVSQCNRSParisFrance
| | - Shaddy Ahmed
- Institut des Géosciences de l'Environnement, de l'Université Grenoble Alpes, CNRS, IRD, Grenoble INPGrenobleFrance
| | - Katie Tuite
- Department of Atmospheric and Oceanic SciencesUniversity of CaliforniaLos AngelesCAUSA
| | - Jochen Stutz
- Department of Atmospheric and Oceanic SciencesUniversity of CaliforniaLos AngelesCAUSA
| | - Aurélien Dommergue
- Institut des Géosciences de l'Environnement, de l'Université Grenoble Alpes, CNRS, IRD, Grenoble INPGrenobleFrance
| | - William R. Simpson
- Geophysical Institute and Department of Chemistry and BiochemistryUniversity of Alaska FairbanksFairbanksAKUSA
| | - Markus M. Frey
- British Antarctic SurveyNatural Environment Research CouncilCambridgeUK
| | - Foteini Baladima
- Institut des Géosciences de l'Environnement, de l'Université Grenoble Alpes, CNRS, IRD, Grenoble INPGrenobleFrance
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3
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Peterson PK, Hartwig M, May NW, Schwartz E, Rigor I, Ermold W, Steele M, Morison JH, Nghiem SV, Pratt KA. Snowpack measurements suggest role for multi-year sea ice regions in Arctic atmospheric bromine and chlorine chemistry. ELEMENTA (WASHINGTON, D.C.) 2019; 7:10.1525/elementa.352. [PMID: 31534978 PMCID: PMC6750228 DOI: 10.1525/elementa.352] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
As sources of reactive halogens, snowpacks in sea ice regions control the oxidative capacity of the Arctic atmosphere. However, measurements of snowpack halide concentrations remain sparse, particularly in the high Arctic, limiting our understanding of and ability to parameterize snowpack participation in tropospheric halogen chemistry. To address this gap, we measured concentrations of chloride, bromide, and sodium in snow samples collected during polar spring above remote multi-year sea ice (MYI) and first-year sea ice (FYI) north of Greenland and Alaska, as well as in the central Arctic, and compared these measurements to a larger dataset collected in the Alaskan coastal Arctic by Krnavek et al. (2012). Regardless of sea ice region, these surface snow samples generally featured lower salinities, compared to coastal snow. Surface snow in FYI regions was typically enriched in bromide and chloride compared to seawater, indicating snowpack deposition of bromine and chlorine-containing trace gases and an ability of the snowpack to participate further in bromine and chlorine activation processes. In contrast, surface snow in MYI regions was more often depleted in bromide, indicating it served as a source of bromine-containing trace gases to the atmosphere prior to sampling. Measurements at various snow depths indicate that the deposition of sea salt aerosols and halogen-containing trace gases to the snowpack surface played a larger role in determining surface snow halide concentrations compared to upward brine migration from sea ice. Calculated enrichment factors for bromide and chloride, relative to sodium, in the MYI snow samples suggests that MYI regions, in addition to FYI regions, have the potential to play an active role in Arctic boundary layer bromine and chlorine chemistry. The ability of MYI regions to participate in springtime atmospheric halogen chemistry should be considered in regional modeling of halogen activation and interpretation of satellite-based tropospheric bromine monoxide column measurements.
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Affiliation(s)
- Peter K. Peterson
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan, US
- Now at Department of Chemistry, Whittier College, Whittier, California, US
| | - Mark Hartwig
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan, US
| | - Nathaniel W. May
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan, US
| | - Evan Schwartz
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan, US
- Now at Department of Molecular Biosciences, University of Texas, Austin, Texas, US
| | - Ignatius Rigor
- Applied Physics Laboratory, University of Washington, Seattle, Washington, US
| | - Wendy Ermold
- Applied Physics Laboratory, University of Washington, Seattle, Washington, US
| | - Michael Steele
- Applied Physics Laboratory, University of Washington, Seattle, Washington, US
| | - James H. Morison
- Applied Physics Laboratory, University of Washington, Seattle, Washington, US
| | - Son V. Nghiem
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, US
| | - Kerri A. Pratt
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan, US
- Department of Earth and Environmental Sciences, University of Michigan, Ann Arbor, Michigan, US
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4
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Abstract
During springtime, the Arctic atmospheric boundary layer undergoes frequent rapid depletions in ozone and gaseous elemental mercury due to reactions with halogen atoms, influencing atmospheric composition and pollutant fate. Although bromine chemistry has been shown to initiate ozone depletion events, and it has long been hypothesized that iodine chemistry may contribute, no previous measurements of molecular iodine (I2) have been reported in the Arctic. Iodine chemistry also contributes to atmospheric new particle formation and therefore cloud properties and radiative forcing. Here we present Arctic atmospheric I2 and snowpack iodide (I-) measurements, which were conducted near Utqiaġvik, AK, in February 2014. Using chemical ionization mass spectrometry, I2 was observed in the atmosphere at mole ratios of 0.3-1.0 ppt, and in the snowpack interstitial air at mole ratios up to 22 ppt under natural sunlit conditions and up to 35 ppt when the snowpack surface was artificially irradiated, suggesting a photochemical production mechanism. Further, snow meltwater I- measurements showed enrichments of up to ∼1,900 times above the seawater ratio of I-/Na+, consistent with iodine activation and recycling. Modeling shows that observed I2 levels are able to significantly increase ozone depletion rates, while also producing iodine monoxide (IO) at levels recently observed in the Arctic. These results emphasize the significance of iodine chemistry and the role of snowpack photochemistry in Arctic atmospheric composition, and imply that I2 is likely a dominant source of iodine atoms in the Arctic.
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Sensitivity of the Reaction Mechanism of the Ozone Depletion Events during the Arctic Spring on the Initial Atmospheric Composition of the Troposphere. ATMOSPHERE 2016. [DOI: 10.3390/atmos7100124] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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6
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Simpson WR, Brown SS, Saiz-Lopez A, Thornton JA, Glasow RV. Tropospheric halogen chemistry: sources, cycling, and impacts. Chem Rev 2015; 115:4035-62. [PMID: 25763598 PMCID: PMC4469175 DOI: 10.1021/cr5006638] [Citation(s) in RCA: 144] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- William R Simpson
- †Department of Chemistry and Biochemistry and Geophysical Institute, University of Alaska Fairbanks, Fairbanks, Alaska 99775, United States
| | - Steven S Brown
- ‡NOAA ESRL Chemical Sciences Division, Boulder, Colorado 80305-3337, United States
| | - Alfonso Saiz-Lopez
- ¶Atmospheric Chemistry and Climate Group, Institute of Physical Chemistry Rocasolano, CSIC, 28006 Madrid, Spain
| | - Joel A Thornton
- §Department of Atmospheric Sciences, University of Washington, Seattle, Washington 98195-1640, United States
| | - Roland von Glasow
- ∥Centre for Ocean and Atmospheric Sciences, School of Environmental Sciences, University of East Anglia, Norwich, Norfolk NR4 7TJ, U.K
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7
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O’Concubhair R, Sodeau JR. The effect of freezing on reactions with environmental impact. Acc Chem Res 2013; 46:2716-24. [PMID: 23829881 DOI: 10.1021/ar400114e] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The knowledge that the freezing process can accelerate certain chemical reactions has been available since the 1960s, particularly in relation to the food industry. However, investigations into such effects on environmentally relevant reactions have only been carried out since the late 1980s. Some 20 years later, the field has matured and scientists have conducted research into various important processes such as the oxidation of nitrite ions to nitrates, sulfites to sulfates, and elemental mercury to inorganic mercury. Field observations mainly carried out in the polar regions have driven this work. For example, researchers have found that both ozone and mercury are removed from the troposphere completely (and almost instantaneously) at the time of Arctic polar sunrise. The monitoring activities suggested that both the phenomena were caused by involvement of bromine (and possibly iodine) chemistry. Scientists investigating the production of interhalide products (bromine and iodine producing interhalides) in frozen aqueous solutions have found that these reactions result in both rate accelerations and unexpected products. Furthermore, these scientists did this research with environmentally relevant concentrations of reagents, thereby suggesting that these reactions could occur in the polar regions. The conversion of elemental mercury to more oxidized forms has also shown that the acceleration of reactions can occur when environmentally relevant concentrations of Hg(0) and oxidants are frozen together in aqueous solutions. These observations, coupled with previous investigations into the effect of freezing on environmental reactions, lead us to conclude that this type of chemistry could potentially play a significant role in the chemical processing of a wide variety of inorganic components in polar regions. More recently, researchers have recognized the implications of these complementary field and laboratory findings toward human health and climate change. In this Account, we focus on the chemical and physical mechanisms that may promote novel chemistry and rate accelerations when water-ice is present. Future prospects will likely concentrate, once again, on the low-temperature chemistry of organic compounds, such as the humic acids, which are known cryospheric contaminants. Furthermore, data on the kinetics and thermodynamics of all types of reaction promoted by the freezing process would provide much assistance in determining their implications to environmental computer models.
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Affiliation(s)
- Ruairí O’Concubhair
- Department of Chemistry and Environmental Research Institute, University College Cork, Cork, Ireland
| | - John R. Sodeau
- Department of Chemistry and Environmental Research Institute, University College Cork, Cork, Ireland
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8
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Nghiem SV, Rigor IG, Richter A, Burrows JP, Shepson PB, Bottenheim J, Barber DG, Steffen A, Latonas J, Wang F, Stern G, Clemente-Colón P, Martin S, Hall DK, Kaleschke L, Tackett P, Neumann G, Asplin MG. Field and satellite observations of the formation and distribution of Arctic atmospheric bromine above a rejuvenated sea ice cover. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/2011jd016268] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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9
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10
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Domine F, Gallet JC, Barret M, Houdier S, Voisin D, Douglas TA, Blum JD, Beine HJ, Anastasio C, Bréon FM. The specific surface area and chemical composition of diamond dust near Barrow, Alaska. ACTA ACUST UNITED AC 2011. [DOI: 10.1029/2011jd016162] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
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11
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Pratte P, Rossi MJ. Heterogeneous Chemistry of Cl 2O and HOCl on Frozen Natural Sea Salt, Recrystallized Sea Salt, KCl and NaCl Solutions at 200 and 215 K. Z PHYS CHEM 2010. [DOI: 10.1524/zpch.2010.6144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Abstract
The HOCl heterogeneous reaction on frozen natural (NSS) and recrystallized (RSS) sea salt, KCl and NaCl solutions was studied using a low pressure flow reactor in order to measure the uptake coefficient γ and products of reaction. The HOCl sample used in these experiments always contained up to 25% Cl2O which was also studied separately as a pure gas in order to understand the heterogeneous chemistry of both gases. By performing HOCl uptake on frozen NSS solution at 200 K and a gas-phase residence time of (1.6±0.6) s we obtained a steady state uptake coefficient γHOCl on NSS = (2.5±0.7)×10-3 and γCl2O on NSS = (2.8±0.8)×10-3. On frozen KCl solution at 200 K we obtain γHOCl on KCl = (2.8±1.3)×10-3, identical to NSS, and γCl2O on KCl = (4.6±0.8)×10-4. The main product formed during the uptake on frozen NSS solution is Cl2 which is sustained for at least one hour. In contrast, only a transient Cl2 flow (pulse) decreasing on the time scale of 100 s was observed on frozen KCl (NaCl) solution. 25±10 % of the HOCl taken up on all chloride-containing frozen substrates at 200 K react to produce Cl2 at high HOCl concentration (4.5×1011 molecule cm-3) and at a residence time of 1.6 s in comparison with twice that for Cl2O. For smaller concentrations such as [HOCl] = 3.7×1010 molecule cm-3 and/or a shorter residence time (0.137±0.004s), HOCl uptake did not generate Cl2 in contrast to Cl2O. A single Br2 burst event was monitored when a Cl2O or HOCl/Cl2O mixture is taken up on fresh frozen NSS solution during the first uptake at 200 K. Further Cl2O or HOCl/Cl2O uptake on the same sample, even after annealing at 240 K does not show an additional Br2 pulse. This Br2 release may be significant in the autocatalytic ozone destruction mechanism in the troposphere during polar sunrise. Some of the atmospheric implications of the present results are highlighted with emphasis on the preequilibrium Cl2O(ads) + H2O(ice) ↔ 2 HOCl(ads) between adsorbed HOCl and Cl2O, with the latter being the gateway to reactive uptake of HOCl at low temperatures.
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Affiliation(s)
- Pascal Pratte
- Ecole Polytechnique Fédérale de Lausanne (EPFL), Laboratoire de Pollution Atmosphérique et sol (LPA, Lausanne, Schweiz
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12
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Abstract
The heterogeneous reactions of SO2 + HOX (X = Cl or Br) --> products on ice surfaces at low temperature have been investigated in a flow reactor coupled with a differentially pumped quadrupole mass spectrometer. Pseudo-first-order loss of SO2 over the ice surfaces has been measured under the conditions of concurrent HOX flow. The initial uptake coefficient of SO2 reaction with HOX has been determined as a function of HOX surface coverage, theta(HOX), on the ice. The initial uptake coefficients increase as the HOX coverage increases. The uptake coefficient can be expressed as gamma(t) = k(h)theta(HOX), where k(h) is an overall rate constant of SO2 + HOCl, which was determined to be (2.3 +/- 0.6) x 10(-19) and (1.7 +/- 0.5) x 10(-19) molecules(-1) x cm2 at 190 and 210 K, and k(h) of SO2 + HOBr is (6.1 +/- 2.0) x 10(-18) molecules(-1) x cm2 at 190 K. theta( HOX) is in the range 8.1 x 10(13)-9.1 x 10(14) molecules x cm(-2). The kinetic results of the heterogeneous reaction of SO2 + HOX on ice surface are interpreted using the Eley-Rideal mechanism. The activation energy of the heterogeneous reaction of SO2 with HOCl on ice surface was determined to be about -37 +/- 10 kJ/mol in the 190-238 K range.
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Affiliation(s)
- Ronghua Jin
- Wadsworth Center, New York State Health Department and Department of Environmental Health Sciences, State University of New York at Albany, P.O. Box 509, Albany, New York 12201-0509, USA
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13
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Pratte P, Rossi MJ. The heterogeneous kinetics of HOBr and HOCl on acidified sea salt and model aerosol at 40–90% relative humidity and ambient temperature. Phys Chem Chem Phys 2006; 8:3988-4001. [PMID: 17028689 DOI: 10.1039/b604321f] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
The HOBr and HOCl uptake coefficient gamma on H(2)SO(4)-acidified submicron salt aerosol of known size distribution was measured in an atmospheric pressure laminar flow reactor. The interaction time of the trace gas with the aerosol was in the range 15 to 90 s and led to gamma values in the range 10(-4) to 10(-2). The acidity of the aerosol is essential in order to enable heterogeneous reactions of HOBr on NaCl, recrystallized sea salt (RSS) and natural sea salt (NSS) aerosols. Specifically, HOCl only reacts on acidified NSS aerosol with a gamma ranging from 0.4 x 10(-3) to 1.8 x 10(-3) at a relative humidity (rh) at 40 and 85%, respectively. Uptake experiments of HOBr on aqueous H(2)SO(4) as well as on H(2)SO(4)-acidified NaCl, RSS or NSS aerosol were performed for rh ranging from 40 to 93%. The gamma value of HOBr on acidified NSS reaches a maximum gamma = 1.9 x 10(-2) at rh = 76 +/- 1% and significantly decreases with increasing rh in contrast to acidified NaCl and RSS aerosols whose gamma values remain high at gamma = (1.0 +/- 0.2) x 10(-2) at rh >/= 80%. An explanation based on the formation of an organic coating on NSS aerosol with increasing rh is proposed.
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Affiliation(s)
- Pascal Pratte
- Ecole Polytechnique Fédérale de Lausanne, Laboratoire de Pollution Atmosphérique et Sol, Bât CH H5, Station 6, CH-1015 Lausanne, Switzerland.
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14
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Bartels-Rausch T, Huthwelker T, Gäggeler HW, Ammann M. Atmospheric Pressure Coated-Wall Flow-Tube Study of Acetone Adsorption on Ice. J Phys Chem A 2005; 109:4531-9. [PMID: 16833789 DOI: 10.1021/jp045187l] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
An atmospheric pressure variant of the coated-wall flow-tube technique in combination with a Monte Carlo simulation is presented. In a performance test of simple first-order wall loss, the Monte Carlo simulation, which uses a simplified model of transport in laminar flow, reproduced results of an analytical solution of the transport equations in a flow tube. This technique was then used to investigate the reversible adsorption of acetone on ice films between 203 and 223 K and a surface coverage of below 5% of a formal monolayer. Simulation of the experimental uptake traces allowed retrieving an adsorption enthalpy of -46 +/- 3 kJ mol(-1) for acetone on ice, which is in good agreement with other static and flow-tube methods. For the experimental conditions adopted here, the transport of acetone molecules along the ice film is governed by equilibrium thermodynamics. Therefore, the surface accommodation coefficient, S(0), and the preexponential factor, tau(0), for the activated desorption cannot be independently determined. These two main microphysical parameters describing partitioning can rather be estimated through their relation to the adsorption entropy. A first estimate for S(0) of acetone on ice in the range of 0.004-0.043 is given.
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15
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Affiliation(s)
- Michel J Rossi
- Laboratoire de Pollution Atmosphérique et Sol (LPAS), Institut des Sciences et Techniques de l'Environnement (ISTE), Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
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16
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Finlayson-Pitts BJ. The Tropospheric Chemistry of Sea Salt: A Molecular-Level View of the Chemistry of NaCl and NaBr. Chem Rev 2003; 103:4801-22. [PMID: 14664634 DOI: 10.1021/cr020653t] [Citation(s) in RCA: 223] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Affiliation(s)
- B J Finlayson-Pitts
- Department of Chemistry, University of California, Irvine, CA 92697-2025, USA.
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17
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Abbatt JPD. Interactions of Atmospheric Trace Gases with Ice Surfaces: Adsorption and Reaction. Chem Rev 2003; 103:4783-800. [PMID: 14664633 DOI: 10.1021/cr0206418] [Citation(s) in RCA: 140] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Affiliation(s)
- Jonathan P D Abbatt
- Department of Chemistry, University of Toronto, 80 St. George Street, Toronto, Ontario, Canada M5S 3H6.
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