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Molecular dynamics simulations of the evaporation of hydrated ions from aqueous solution. Commun Chem 2022; 5:55. [PMID: 36698011 PMCID: PMC9814746 DOI: 10.1038/s42004-022-00669-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2021] [Accepted: 03/22/2022] [Indexed: 01/28/2023] Open
Abstract
Although important for atmospheric processes and gas-phase catalysis, very little is known about the hydration state of ions in the vapor phase. Here we study the evaporation energetics and kinetics of a chloride ion from liquid water by molecular dynamics simulations. As chloride permeates the interface, a water finger forms and breaks at a chloride separation of ≈ 2.8 nm from the Gibbs dividing surface. For larger separations from the interface, about 7 water molecules are estimated to stay bound to chloride in saturated water vapor, as corroborated by continuum dielectrics and statistical mechanics models. This ion hydration significantly reduces the free-energy barrier for evaporation. The effective chloride diffusivity in the transition state is found to be about 6 times higher than in bulk, which reflects the highly mobile hydration dynamics as the water finger breaks. Both effects significantly increase the chloride evaporation flux from the quiescent interface of an electrolyte solution, which is predicted from reaction kinetic theory.
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Jiao X, He C, Yu H, He J, Wang C. Photo-generated hydroxyl radicals contribute to the formation of halogen radicals leading to ozone depletion on and within polar stratospheric clouds surface. CHEMOSPHERE 2022; 291:132816. [PMID: 34752833 DOI: 10.1016/j.chemosphere.2021.132816] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/02/2021] [Revised: 11/02/2021] [Accepted: 11/05/2021] [Indexed: 06/13/2023]
Abstract
Polar stratospheric clouds (PSCs), of which the surface is a dynamic liquid water layer and might consist of aqueous HNO3 and H2O2, is a well-known key meteorological condition contributing to the ozone hole in the polar stratosphere. PSCs has been considered to provide abundant surface for the heterogeneous reactions causing the formation of the Cl2 and HOCl, which are further photolyzed into Cl and ClO radicals leading to the ozone destruction. Here we demonstrated that the sunlight drives the massive and stable production of OH radicals in aqueous HNO3 and its main photo-induced byproduct HNO2. We also found that the photo-generated OH radicals in aqueous HNO3, HNO2 and H2O2 have the remarkable capability to react with the dissolved HCl, Cl- and Br- to form halogen radicals. In addition, we observed that the H2O2 can react with dissolved HCl and Br- in darkness to form and release Cl2 and Br2 gases, which could further be photolyzed into reactive halogen radicals whenever sunlight is available. All these findings suggest that, except for the well-known heterogeneous reactions, photochemical reactions involving the aqueous HNO3 and H2O2 on and within PSCs surface might constitute another important halogen activation pathway for ozone destruction. This study may shed deeper insights into the mechanism of halogen radicals resulting in ozone depletion in polar stratosphere.
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Affiliation(s)
- Xiaoyu Jiao
- College of Resources and Environmental Science, South-Central University for Nationalities, Wuhan, 430074, China
| | - Congcong He
- College of Resources and Environmental Science, South-Central University for Nationalities, Wuhan, 430074, China
| | - Huan Yu
- School of Environmental Studies, China University of Geosciences, Wuhan, 430074, China
| | - Jun He
- Department of Chemical and Environmental Engineering, University of Nottingham Ningbo China, Ningbo, 315100, China
| | - Chengjun Wang
- College of Resources and Environmental Science, South-Central University for Nationalities, Wuhan, 430074, China.
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3
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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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Stojanović L, Rodrigues GP, Aziz SG, Hilal RH, Barbatti M. Photochemistry of methyl hypobromite (CH3OBr): excited states and photoabsorption spectrum. RSC Adv 2015. [DOI: 10.1039/c5ra18578e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
From photoabsorption to photodissociation, from MRCI to TDDFT; a comprehensive benchmark on the photochemistry of methyl hypobromite (CH3OBr) is provided.
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Affiliation(s)
| | - Gessenildo Pereira Rodrigues
- Max-Planck-Institut für Kohlenforschung
- 45470 Mülheim an der Ruhr
- Germany
- Universidade Federal da Paraiba
- João Pessoa
| | - Saadullah G. Aziz
- Chemistry Department
- Faculty of Science
- King Abdulaziz University
- Jeddah B.O. 208203
- Saudi Arabia
| | - Rifaat H. Hilal
- Chemistry Department
- Faculty of Science
- King Abdulaziz University
- Jeddah B.O. 208203
- Saudi Arabia
| | - Mario Barbatti
- Max-Planck-Institut für Kohlenforschung
- 45470 Mülheim an der Ruhr
- Germany
- Aix Marseille Université
- CNRS
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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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7
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Kong Q, Wulff M, Lee JH, Bratos S, Ihee H. Photochemical Reaction Pathways of Carbon Tetrabromide in Solution Probed by Picosecond X-ray Diffraction. J Am Chem Soc 2007; 129:13584-91. [DOI: 10.1021/ja073503e] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Affiliation(s)
- Qingyu Kong
- Contribution from the European Synchrotron Radiation Facility, Grenoble Cedex 38043, BP 220, France, National Creative Research Initiative Center for Time-Resolved Diffraction, Department of Chemistry and School of Molecular Science (BK21), Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 305-701, Republic of Korea, and Laboratoire de Physique, Théorique des Liquides, Université Pierre et Marie Curie, Case Courrier 121, 4 Place Jussieu, Paris Cedex 75252, France
| | - Michael Wulff
- Contribution from the European Synchrotron Radiation Facility, Grenoble Cedex 38043, BP 220, France, National Creative Research Initiative Center for Time-Resolved Diffraction, Department of Chemistry and School of Molecular Science (BK21), Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 305-701, Republic of Korea, and Laboratoire de Physique, Théorique des Liquides, Université Pierre et Marie Curie, Case Courrier 121, 4 Place Jussieu, Paris Cedex 75252, France
| | - Jae Hyuk Lee
- Contribution from the European Synchrotron Radiation Facility, Grenoble Cedex 38043, BP 220, France, National Creative Research Initiative Center for Time-Resolved Diffraction, Department of Chemistry and School of Molecular Science (BK21), Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 305-701, Republic of Korea, and Laboratoire de Physique, Théorique des Liquides, Université Pierre et Marie Curie, Case Courrier 121, 4 Place Jussieu, Paris Cedex 75252, France
| | - Savo Bratos
- Contribution from the European Synchrotron Radiation Facility, Grenoble Cedex 38043, BP 220, France, National Creative Research Initiative Center for Time-Resolved Diffraction, Department of Chemistry and School of Molecular Science (BK21), Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 305-701, Republic of Korea, and Laboratoire de Physique, Théorique des Liquides, Université Pierre et Marie Curie, Case Courrier 121, 4 Place Jussieu, Paris Cedex 75252, France
| | - Hyotcherl Ihee
- Contribution from the European Synchrotron Radiation Facility, Grenoble Cedex 38043, BP 220, France, National Creative Research Initiative Center for Time-Resolved Diffraction, Department of Chemistry and School of Molecular Science (BK21), Korea Advanced Institute of Science and Technology (KAIST), Daejeon, 305-701, Republic of Korea, and Laboratoire de Physique, Théorique des Liquides, Université Pierre et Marie Curie, Case Courrier 121, 4 Place Jussieu, Paris Cedex 75252, France
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Kong Q, Wulff M, Bratos S, Vuilleumier R, Kim J, Ihee H. Structure of the photodissociation products of CCl4, CBr4, and CI4 in solution studied by DFT and ab initio calculations. J Phys Chem A 2007; 110:11178-87. [PMID: 16986853 DOI: 10.1021/jp062919w] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Various molecular species that can be populated during the photoreaction of carbon tetrahalides CX(4) (X = Cl, Br, I) in the gas phase and in solution have been studied by ab initio and density functional theory (DFT) calculations. Geometries, energies, and vibrational frequencies of CX(4), CX(3), CX(2), C(2)X(6), C(2)X(5), C(2)X(4), X(2), and the isomer X(2)CX-X were calculated and transition states connecting these species were characterized. Spin-orbit DFT (SODFT) computations were also performed to include the relativistic effects, which cannot be neglected for Br and I atoms. The calculated potential energy surfaces satisfactorily describe the reactions of the photoexcited CX(4) molecules. In the gas phase, the initial C-X bond rupture in CX(4) is followed by secondary C-X breakage in the CX(3) radical, leading to CX(2) and 2X, and the formation of C(2)X(6) or C(2)X(4) through bimolecular recombination of the CX(3) or CX(2) radicals is favored thermodynamically. In solution, by contrast, the X(2)CX-X isomer is formed via X-X binding, and two CX(3) radicals recombine nongeminately to form C(2)X(6), which then dissociates into C(2)X(4) and X(2) through C(2)X(5). The Raman intensities and the vibrational frequencies, as well as the absorption spectra and oscillator strengths of the Br(2)CBr-Br isomer in the gas phase and in various solvents were computed and the calculated absorption and Raman spectra of the Br(2)CBr-Br isomer in various solutions are in good agreement with the experimental data. The natural population analysis indicates that the Br(2)CBr-Br isomer corresponds to the recently reported solvent-stabilized solvated ion pair (CBr(3)(+)//Br(-))(solv) in the highly polar alcohol solvent. The singlet-triplet energy separations of the CX(2) radicals in the gas phase and in solution were evaluated with high level computational methods, and the optimized geometric parameters are in good agreement with the experimental results. The geometric and energetic differences between the singlet and triplet states were explained by the electronic properties of the CX(2) radicals. C(2)X(4), C(2)X(5), and C(2)X(6) (X = Br, I) in the gas phase and in solution were optimized at different computational levels, and the optimized geometric parameters of C(2)I(4) are in very good agreement with the experimental data.
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Affiliation(s)
- Qingyu Kong
- European Synchrotron Radiation Facility, Grenoble Cedex 38043, BP 220, France.
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Li YL, Zuo P, Phillips DL. A Density Functional Theory Study of the Reactions of Dichlorocarbene and Isodichloromethane with H2O. MOLECULAR SIMULATION 2006. [DOI: 10.1080/0892702031000152109] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Affiliation(s)
- Thomas Huthwelker
- Laboratory for Radio- and Environmental Chemistry, Paul Scherrer Institute, CH-5232 Villigen, Switzerland
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11
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Zeng T, Wang Y, Chance K, Blake N, Blake D, Ridley B. Halogen-driven low-altitude O3and hydrocarbon losses in spring at northern high latitudes. ACTA ACUST UNITED AC 2006. [DOI: 10.1029/2005jd006706] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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12
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Du Y, Guan X, Kwok WM, Chu LM, Phillips DL. Comparison of the Dehalogenation of Dihalomethanes (CH2XI, where X = Cl, Br, I) Following Ultraviolet Photolysis in Aqueous and NaCl Saltwater Environments. J Phys Chem A 2005; 109:5872-82. [PMID: 16833922 DOI: 10.1021/jp0504928] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The ultraviolet photolysis of low concentrations of CH(2)XI (X = Cl, Br, I) were investigated in water and saltwater solutions by photochemistry and picosecond time-resolved resonance Raman spectroscopy. Photolysis in both kinds of solutions formed mostly CH(2)(OH)(2) and HI and HX products. However, photolysis of the CH(2)XI molecules in saltwater resulted in production of some CH(2)XCl products not observed in aqueous solutions without salt present. The appearance of these new products in saltwater solutions is accompanied by a decrease in the amount of CH(2)(OH)(2), HI, and HX products compared to photolysis in aqueous solutions without salt present. The possible implications for photolysis of CH(2)XI and other polyhalomethanes in seawater and other salt aqueous environments compared to nonsaltwater solvated environments is briefly discussed.
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Affiliation(s)
- Yong Du
- Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong S.A.R., P.R. China
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Lin X, Zhao C, Phillips DL. Anab initiostudy of the reactions of CH2X-X (X=Cl, Br, I) isopolyhalomethanes with nCH3OH. MOLECULAR SIMULATION 2005. [DOI: 10.1080/08927020412331337050] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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14
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Zhao C, Lin X, Kwok WM, Guan X, Du Y, Wang D, Hung KF, Phillips DL. Water-Catalyzed Dehalogenation Reactions of the Isomer of CBr4 and Its Reaction Products and a Comparison to Analogous Reactions of the Isomers of Di- and Trihalomethanes. Chemistry 2005; 11:1093-108. [PMID: 15742469 DOI: 10.1002/chem.200400695] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
A combined experimental and theoretical study of the UV photolysis of a typical tetrahalomethane, CBr4, in water and acetonitrile/water was performed. Ultraviolet photolysis of low concentrations of CBr4 in water mostly leads to the production of four HBr leaving groups and CO2. Picosecond time-resolved resonance Raman (Ps-TR3) experiments and ab initio calculations indicate that water-catalyzed O-H insertion/HBr elimination of the isomer of CBr4 and subsequent reactions of its products lead to the formation of these products. The UV photolyses of di-, tri-, and tetrahalomethanes at low concentrations in water-solvated environments are compared to one another. This comparison enables a general reaction scheme to be deduced that can account for the different products produced by UV photolysis of low concentrations of di-, tri-, and tetrahalomethanes in water. The fate of the (halo)formaldehyde intermediate in the chemical reaction mechanism is the key to determining how many strong acid leaving groups are produced and which carbon atom final product is likely formed by UV photolysis of a polyhalomethane at low concentrations in a water-solvated environment.
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Affiliation(s)
- Cunyuan Zhao
- Department of Chemistry, University of Hong Kong, Pokfulam Road, Hong Kong, P. R. China
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15
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Lin X, Guan X, Kwok WM, Zhao C, Du Y, Li YL, Phillips DL. Water-Catalyzed O−H Insertion/HI Elimination Reactions of Isodihalomethanes (CH2X−I, Where X = Cl, Br, I) with Water and the Dehalogenation of Dihalomethanes in Water-Solvated Environments. J Phys Chem A 2005; 109:981-98. [PMID: 16833405 DOI: 10.1021/jp0450843] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
A combined experimental and theoretical investigation of the ultraviolet photolysis of CH2XI (where X = Cl, Br, I) dihalomethanes in water is presented. Ultraviolet photolysis of low concentrations of CH2XI (where X = Cl, Br, I) in water appears to lead to almost complete conversion into CH2(OH)2 and HX and HI products. Picosecond time-resolved resonance Raman (ps-TR3) spectroscopy experiments revealed that noticeable amounts of CH2X-I isodihalomethane intermediates were formed within several picoseconds after photolysis of the CH2XI parent compound in mixed aqueous solutions. The ps-TR3 experiments in mixed aqueous solutions revealed that the decay of the CH2X-I isodihalomethane intermediates become significantly shorter as the water concentration increases, indicating that the CH2X-I intermediates may be reacting with water. Ab initio calculations found that the CH2X-I intermediates are able to react relatively easily with water via a water-catalyzed O-H insertion/HI elimination reaction to produce CH2X(OH) and HI products, with the barrier for these reactions increasing as X changes from Cl to Br to I. The ab initio calculations also found that the CH2X(OH) product can undergo a water-catalyzed HX elimination reaction to make H2C=O and HX products, with the barrier to reaction decreasing as X changes from Cl to Br to I. The preceding two water-catalyzed reactions produce the HI and HX leaving groups observed experimentally, and the H2C=O product further reacts with water to make the other CH2(OH)2 product observed in the photochemistry experiments. This suggests that that the CH2X-I intermediates react with water to form the CH2(OH)2 and HI and HX products observed in the photochemistry experiments. Ultraviolet photolysis of CH2XI (where X = Cl, Br, I) at low concentrations in water-solvated environments appears to lead to efficient dehalogenation and release of two strong acid leaving groups. We very briefly discuss the potential influence of this photochemistry in water on the decomposition of polyhalomethanes and halomethanols in aqueous environments.
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Affiliation(s)
- Xufeng Lin
- Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong S.A.R., P. R. China
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16
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Yang X, Cox RA, Warwick NJ, Pyle JA, Carver GD, O'Connor FM, Savage NH. Tropospheric bromine chemistry and its impacts on ozone: A model study. ACTA ACUST UNITED AC 2005. [DOI: 10.1029/2005jd006244] [Citation(s) in RCA: 204] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
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17
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Santschi C, Rossi MJ. The heterogeneous interaction of HOCl with solid KBr substrates: The catalytic role of adsorbed halogens. Phys Chem Chem Phys 2005; 7:2599-609. [PMID: 16189570 DOI: 10.1039/b503071d] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The heterogeneous reactivity of HOCl on solid KBr at ambient temperature has been studied using a Knudsen flow reactor. On solid KBr steady-state uptake experiments reveal the formation of Br- and Cl-containing reaction products formed in secondary reactions such as Br(2), BrCl, HOBr, BrOCl, Cl(2) and Cl(2)O with the latter two predominating in the late stages of the reaction. The uptake coefficient gamma spanning a range between 0.15 and 1 x 10(-3) and product yields of HOCl strongly depend on the nature of the solid sample, whether grain, ground grain or thin sprayed film, as well as on sample processing such as pumping and/or heating. Furthermore, the presence of adsorbed halogen species such as Br(2)(a) are crucial for the kinetics of the reaction of HOCl with solid KBr substrates. The presence of surface-adsorbed water (SAW) leads to deactivation of KBr whereas mechanical stress such as grinding leads to the formation of surface defects that become reaction centers. Desorption of SAW at T > 620 K induces high reactivity of the KBr sample at ambient temperature. A reaction mechanism encompassing all significant observations including unusual autocatalytic activity is given as there is no direct reaction of HOCl with solid KBr. It stresses the importance of adsorbed Br-containing species such as Br(2)(a) and HBr(a) that initiate the heterogeneous chemistry of HOCl on solid KBr in the presence of SAW. The role of surface acidity and SAW for the extent of reaction is emphasized.
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Affiliation(s)
- Ch Santschi
- Laboratoire de Pollution Atmosphérique et Sol (LPAS), Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
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18
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Fleischmann OC, Hartmann M, Burrows JP, Orphal J. New ultraviolet absorption cross-sections of BrO at atmospheric temperatures measured by time-windowing Fourier transform spectroscopy. J Photochem Photobiol A Chem 2004. [DOI: 10.1016/j.jphotochem.2004.03.026] [Citation(s) in RCA: 162] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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19
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Kwok WM, Zhao C, Guan X, Li YL, Du Y, Phillips DL. Efficient dehalogenation of polyhalomethanes and production of strong acids in aqueous environments: Water-catalyzed O–H-insertion and HI-elimination reactions of isodiiodomethane (CH2I–I) with water. J Chem Phys 2004; 120:9017-32. [PMID: 15267837 DOI: 10.1063/1.1701699] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
A combined experimental and theoretical study of the ultraviolet photolysis of CH2I2 in water is reported. Ultraviolet photolysis of low concentrations of CH2I2 in water was experimentally observed to lead to almost complete conversion into CH2(OH)2 and 2HI products. Picosecond time-resolved resonance Raman spectroscopy experiments in mixed water/acetonitrile solvents (25%-75% water) showed that appreciable amounts of isodiiodomethane (CH2I-I) were formed within several picoseconds and the decay of the CH2I-I species became substantially shorter with increasing water concentration, suggesting that CH2I-I may be reacting with water. Ab initio calculations demonstrate the CH2I-I species is able to react readily with water via a water-catalyzed O--H-insertion and HI-elimination reaction followed by its CH2I(OH) product undergoing a further water-catalyzed HI-elimination reaction to make a H2C=O product. These HI-elimination reactions produce the two HI leaving groups observed experimentally and the H2C=O product further reacts with water to produce the other final CH2(OH)2 product observed in the photochemistry experiments. These results suggest that CH2I-I is the species that reacts with water to produce the CH2(OH)2 and 2HI products seen in the photochemistry experiments. The present study demonstrates that ultraviolet photolysis of CH2I2 at low concentration leads to efficient dehalogenation and release of multiple strong acid (HI) leaving groups. Some possible ramifications for the decomposition of polyhalomethanes and halomethanols in aqueous environments as well as the photochemistry of polyhalomethanes in the natural environment are briefly discussed.
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Affiliation(s)
- Wai Ming Kwok
- Department of Chemistry, University of Hong Kong, Pokfulam Road, Hong Kong, China
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20
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Frieß U, Hollwedel J, König-Langlo G, Wagner T, Platt U. Dynamics and chemistry of tropospheric bromine explosion events in the Antarctic coastal region. ACTA ACUST UNITED AC 2004. [DOI: 10.1029/2003jd004133] [Citation(s) in RCA: 109] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- U. Frieß
- Institut für Umweltphysik; University of Heidelberg; Heidelberg Germany
| | - J. Hollwedel
- Institut für Umweltphysik; University of Heidelberg; Heidelberg Germany
| | - G. König-Langlo
- Alfred Wegener Institut für Polar- und Meeresforschung; Bremerhaven Germany
| | - T. Wagner
- Institut für Umweltphysik; University of Heidelberg; Heidelberg Germany
| | - U. Platt
- Institut für Umweltphysik; University of Heidelberg; Heidelberg Germany
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Kwok WM, Zhao C, Li YL, Guan X, Wang D, Phillips DL. Water-Catalyzed Dehalogenation Reactions of Isobromoform and Its Reaction Products. J Am Chem Soc 2004; 126:3119-31. [PMID: 15012142 DOI: 10.1021/ja0390552] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A combined experimental and theoretical study of the photochemistry of CHBr(3) in pure water and in acetonitrile/water mixed solvents is reported that elucidates the reactions and mechanisms responsible for the photochemical conversion of the halogen atoms in CHBr(3) into three bromide ions in water solution. Ultraviolet excitation at 240 nm of CHBr(3) (9 x 10(-)(5) M) in water resulted in almost complete conversion into 3HBr leaving groups and CO (major product) and HCOOH (minor product) molecules. Picosecond time-resolved resonance Raman (ps-TR(3)) experiments and ab initio calculations indicate that the water-catalyzed O-H insertion/HBr elimination reaction of isobromoform and subsequent reactions of its products are responsible for the production of the final products observed following ultraviolet excitation of CHBr(3) in water. These results have important implications for the phase-dependent behavior of polyhalomethane photochemistry and chemistry in water-solvated environments as compared to gas-phase reactions. The dissociation reaction of HBr into H(+) and Br(-) ions is the driving force for several O-H insertion and HBr elimination reactions and allows O-H and C-H bonds to be cleaved more easily than in the absence of water molecules. This water-catalysis by solvation of a leaving group and its dissociation into ions (e.g., H(+) and Br(-) in the examples investigated here) may occur for a wide range of chemical reactions taking place in water-solvated environments.
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Affiliation(s)
- Wai Ming Kwok
- Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong S.A.R., P. R. China
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22
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Kwok WM, Zhao C, Li YL, Guan X, Phillips DL. Direct observation of an isopolyhalomethane O–H insertion reaction with water: Picosecond time-resolved resonance Raman (ps-TR3) study of the isobromoform reaction with water to produce a CHBr2OH product. J Chem Phys 2004; 120:3323-32. [PMID: 15268486 DOI: 10.1063/1.1640997] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Picosecond time-resolved resonance Raman (ps-TR3) spectroscopy was used to obtain the first definitive spectroscopic observation of an isopolyhalomethane O-H insertion reaction with water. The ps-TR3 spectra show that isobromoform is produced within several picoseconds after photolysis of CHBr3 and then reacts on the hundreds of picosecond time scale with water to produce a CHBr2OH reaction product. Photolysis of low concentrations of bromoform in aqueous solution resulted in noticeable formation of HBr strong acid. Ab initio calculations show that isobromoform can react with water to produce a CHBr2(OH) O-H insertion reaction product and a HBr leaving group. This is consistent with both the ps-TR3 experiments that observe the reaction of isobromoform with water to form a CHBr2(OH) product and photolysis experiments that show HBr acid formation. We briefly discuss the implications of these results for the phase dependent behavior of polyhalomethane photochemistry in the gas phase versus water solvated environments.
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Affiliation(s)
- Wai Ming Kwok
- Department of Chemistry, University of Hong Kong, Pokfulam Road, Hong Kong, People's Republic of China
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23
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Liu D, Ma G, Levering LM, Allen HC. Vibrational Spectroscopy of Aqueous Sodium Halide Solutions and Air−Liquid Interfaces: Observation of Increased Interfacial Depth. J Phys Chem B 2004. [DOI: 10.1021/jp036169r] [Citation(s) in RCA: 416] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Dingfang Liu
- Department of Chemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210
| | - Gang Ma
- Department of Chemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210
| | - Lori M. Levering
- Department of Chemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210
| | - Heather C. Allen
- Department of Chemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210
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24
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Santos CMP, Faria R, Machado SP, De Almeida WB. An ab initio correlated study of the potential energy surface for the HOBr.H[sub 2]O complex. J Chem Phys 2004; 121:141-8. [PMID: 15260531 DOI: 10.1063/1.1755191] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023] Open
Abstract
The potential energy surface (PES) for the HOBr.H(2)O complex has been investigated using second- and fourth-order Møller-Plesset perturbation theory (MP2, MP4) and coupled cluster theory with single and doubles excitations (CCSD), and a perturbative approximation of triple excitations (CCSD-T), correlated ab initio levels of theory employing basis sets of triple zeta quality with polarization and diffuse functions up to the 6-311++G(3dp,3df ) standard Pople's basis set. Six stationary points being three minima, two first-order transition state (TS) structures and one second-order TS were located on the PES. The global minimum syn and the anti equilibrium structure are virtually degenerated [DeltaE(ele-nuc) approximately 0.3 kcal mol(-1), CCSD-T/6-311++G(3df,3pd) value], with the third minima being approximately 4 kcal mol(-1) away. IRC analysis was performed to confirm the correct connectivity of the two first-order TS structures. The CCSD-T/6-311++G(3df,3pd)//MP2/6-311G(d,p) barrier for the syn<-->anti interconversion is 0.3 kcal mol(-1), indicating that a mixture of the syn and anti forms of the HOBr.H(2)O complex is likely to exist.
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Affiliation(s)
- Cristina Maria P Santos
- Laboratório de Química Inorgânica Computacional, Departamento de Química Inorgânica, Instituto de Química, Universidade Federal do Rio de Janeiro (UFRJ), Caixa Postal 68563, Rio de Janeiro, RJ, 21.945-970, Brazil
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25
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Guan X, Du Y, Li YL, Kwok WM, Phillips DL. Comparison of the dehalogenation of polyhalomethanes and production of strong acids in aqueous and salt (NaCl) water environments: Ultraviolet photolysis of CH[sub 2]I[sub 2]. J Chem Phys 2004; 121:8399-409. [PMID: 15511161 DOI: 10.1063/1.1803508] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The ultraviolet photolysis of CH(2)I(2) was studied in water and salt water solutions using photochemistry and picosecond time-resolved resonance Raman spectroscopy. Photolysis in both types of environments produces mainly CH(2)(OH)(2) and HI products. However, photolysis of CH(2)I(2) in salt water leads to the formation of different products/intermediates (CH(2)ICl and Cl(2) (-)) not observed in the absence of salt in aqueous solutions. The amount of CH(2)(OH)(2) and HI products appears to decrease after photolysis of CH(2)I(2) in salt water compared to pure water. We briefly discuss possible implications of these results for photolysis of CH(2)I(2) and other polyhalomethanes in sea water and other salt aqueous environments compared to nonsalt water solvated environments.
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Affiliation(s)
- Xiangguo Guan
- Department of Chemistry, University of Hong Kong, Pokfulam Road, Hong Kong, People's Republic of China
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26
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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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27
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Weiss-Penzias P, Jaffe DA, McClintick A, Prestbo EM, Landis MS. Gaseous elemental mercury in the marine boundary layer: evidence for rapid removal in anthropogenic pollution. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2003; 37:3755-3763. [PMID: 12967093 DOI: 10.1021/es0341081] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
In this study, gas-phase elemental mercury (Hg0) and related species (including inorganic reactive gaseous mercury (RGM) and particulate mercury (PHg)) were measured at Cheeka Peak Observatory (CPO), Washington State, in the marine boundary layer during 2001-2002. Air of continental origin containing anthropogenic pollutants from the urban areas to the east contained on average 5.3% lower Hg0 levels as compared to the marine background. This result is difficult to reconcile since it is known that industrial emissions in our region are sources of Hg0. The rate of removal of Hg0 from a pollution plume necessary to account for our observations is inconsistent with the accepted view of Hg0 as a stable atmospheric pollutant. The largest and most frequent Hg0 loss events occurred in the presence of increased ozone (O3) during the summer. Hg0 and O3 also display diurnal cycles that are out-of-phase with one another. In other seasons Hg0 behavior is less consistent, as we observe weak positive correlations with O3 and occasional Hg0 enhancements in local pollution. RGM and PHg concentrations are enhanced only slightly during Hg0 loss events, comprising a small fraction of the mercury pool (approximately 3%). Long-range transported pollution of Asian origin was also detected at CPO, and this contains both higher and lower levels of Hg0 as compared to the background with maximum changes being <20%. Here, the more photochemically processed the air mass, as determined by propane/ethane ratios, the more likely we are to observe Hg0 loss. Air from the marine background in summer displays a significant diurnal cycle with a phase that matches the diurnal cycles seen in polluted air masses. A Junge lifetime for Hg0 in the clean marine boundary layer is calculated to be 7.1 months, which is on the low end of previous estimates (0.5-2 yr).
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Affiliation(s)
- Peter Weiss-Penzias
- Interdisciplinary Arts and Sciences, University of Washington-Bothell, 18115 Campus Way NE, Bothell, Washington 98011, USA.
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Li YL, Zhao C, Kwok WM, Guan X, Zuo P, Phillips DL. Observation of a HI leaving group following ultraviolet photolysis of CH2I2 in water and anab initioinvestigation of the O–H insertion/HI elimination reactions of the CH2I–I isopolyhalomethane species with H2O and 2H2O. J Chem Phys 2003. [DOI: 10.1063/1.1595636] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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29
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Santos CMP, Faria RB, De Almeida WB, Machuca-Herrera JO, Machado SP. Geometrical and vibrational DFT studies of HOBr·(H2O)n clusters (n = 14). CAN J CHEM 2003. [DOI: 10.1139/v03-101] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The geometrical structures and the vibrational spectra of the HOBr·(H2O)n clusters (n = 14) have been calculated at the DFT level of theory, using the pBP method and the DN* and DN** numerical basis sets. The results showed that the interaction involving the H of the HOBr and the O of the water molecule represent the preferred arrangements for these hydrated compounds. Both HOBr·H2O and HOBr·(H2O)2 clusters presented stable structures with syn and anti conformations, the syn being the most stable. The HOBr·(H2O)3 and the HOBr·(H2O)4 clusters have presented stable cyclic structures. In the HOBr·H2O and HOBr·(H2O)2 clusters, low-frequency stretching values could be assigned to hydrogen bonds, but the same could not be done so clearly for the HOBr·(H2O)3 and the HOBr·(H2O)4 cyclic clusters. The binding energies were also determinated for these HOBr hydrated clusters, showing that the addition of a water molecule to the HOBr·H2O and HOBr·(H2O)2 clusters increases the binding energy by approximately 4 kcal mol1, while the addition of a water molecule to the HOBr·(H2O)3 cluster decreases this value by 4 kcal mol1.Key words: DFT, numerical basis, HOBr·(H2O)n, clusters.
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Abstract
While the role of reactive halogen species (e.g. Cl, Br) in the destruction of the stratospheric ozone layer is well known, their role in the troposphere was investigated only since their destructive effect on boundary layer ozone after polar sunrise became obvious. During these 'Polar Tropospheric Ozone Hole' events O(3) is completely destroyed in the lowest approximately 1000 m of the atmosphere on areas of several million square kilometres. Up to now it was assumed that these events were confined to the polar regions during springtime. However, during the last few years significant amounts of BrO and Cl-atoms were also found outside the Arctic and Antarctic boundary layer. Recently even higher BrO mixing ratios (up to 176 ppt) were detected by optical absorption spectroscopy (DOAS) in the Dead Sea basin during summer. In addition, evidence is accumulating that BrO (at levels around 1-2 ppt) is also occurring in the free troposphere at all latitudes. In contrast to the stratosphere, where halogens are released from species, which are very long lived in the troposphere, likely sources of boundary layer Br and Cl are autocatalytic oxidation of sea salt halides (the 'Bromine Explosion'), while precursors of free tropospheric BrO and coastal IO probably are short-lived organo-halogen species. At the levels suggested by the available measurements reactive halogen species have a profound effect on tropospheric chemistry: In the polar boundary layer during 'halogen events' ozone is usually completely lost within hours or days. In the free troposphere the effective O(3)-losses due to halogens could be comparable to the known photochemical O(3) destruction. Further interesting consequences include the increase of OH levels and (at low NO(X)) the decrease of the HO(2)/OH ratio in the free troposphere.
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Affiliation(s)
- U Platt
- Institut für Umweltphysik, University of Heidelberg, INF 229, D-69120 Heidelberg, Germany.
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31
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Voegele AF, Tautermann CS, Loerting T, Liedl KR. Reactions of HOBr + HCl + nH2O and HOBr + HBr + nH2O. Chem Phys Lett 2003. [DOI: 10.1016/s0009-2614(03)00447-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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32
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Avallone LM, Toohey DW, Fortin TJ, McKinney KA, Fuentes JD. In situ measurements of bromine oxide at two high-latitude boundary layer sites: Implications of variability. ACTA ACUST UNITED AC 2003. [DOI: 10.1029/2002jd002843] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Linnea M. Avallone
- Laboratory for Atmospheric and Space Physics; University of Colorado at Boulder; Boulder Colorado USA
- Program in Atmospheric and Oceanic Sciences; University of Colorado at Boulder; Boulder Colorado USA
| | - Darin W. Toohey
- Program in Atmospheric and Oceanic Sciences; University of Colorado at Boulder; Boulder Colorado USA
| | - Tara J. Fortin
- Department of Chemistry and Biochemistry; University of Colorado at Boulder; Boulder Colorado USA
| | - Karena A. McKinney
- Department of Geology; California Institute of Technology; Pasadena California USA
| | - Jose D. Fuentes
- Department of Environmental Science; University of Virginia; Charlottesville Virginia USA
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33
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Cantrell CA. Steady state free radical budgets and ozone photochemistry during TOPSE. ACTA ACUST UNITED AC 2003. [DOI: 10.1029/2002jd002198] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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34
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Ridley BA. Ozone depletion events observed in the high latitude surface layer during the TOPSE aircraft program. ACTA ACUST UNITED AC 2003. [DOI: 10.1029/2001jd001507] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
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35
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Pundt I, Pommereau J, Chipperfield MP, Van Roozendael M, Goutail F. Climatology of the stratospheric BrO vertical distribution by balloon‐borne UV–visible spectrometry. ACTA ACUST UNITED AC 2002. [DOI: 10.1029/2002jd002230] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- I. Pundt
- Service d'Aéronomie CNRS Verrières‐le‐Buisson France
- Now at Institute of Environmental Physics, University of Heidelberg, Im Neuenheimer Feld 229, 69120 Heidelberg, Germany
| | | | | | | | - F. Goutail
- Service d'Aéronomie CNRS Verrières‐le‐Buisson France
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36
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Li YL, Wang D, Phillips DL. Time-resolved resonance Raman spectroscopy and density functional theory investigation of the CH2I–I isomer and CH2I2⋯I molecular complex products produced from ultraviolet photolysis of CH2I2 in the solution phase: Comparison of the structure and chemical reactivity of polyhalomethane isomers and polyhalomethane–halogen atom molecular complexes. J Chem Phys 2002. [DOI: 10.1063/1.1511724] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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37
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von Glasow R, Sander R, Bott A, Crutzen PJ. Modeling halogen chemistry in the marine boundary layer 1. Cloud-free MBL. ACTA ACUST UNITED AC 2002. [DOI: 10.1029/2001jd000942] [Citation(s) in RCA: 105] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Affiliation(s)
- Roland von Glasow
- Atmospheric Chemistry Division; Max-Planck-Institut für Chemie; Mainz Germany
| | - Rolf Sander
- Atmospheric Chemistry Division; Max-Planck-Institut für Chemie; Mainz Germany
| | - Andreas Bott
- Meteorologisches Institut; Universität Bonn; Bonn Germany
| | - Paul J. Crutzen
- Atmospheric Chemistry Division; Max-Planck-Institut für Chemie; Mainz Germany
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38
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Li YL, Wang D, Phillips DL. Transient Resonance Raman Spectroscopy and Density Functional Theory Investigation of Iso-Dibromoacetic Acid Photoproduct Produced From Ultraviolet Photolysis of Dibromoacetic Acid in the Solution Phase. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2002. [DOI: 10.1246/bcsj.75.943] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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39
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Ebinghaus R, Kock HH, Temme C, Einax JW, Lowe AG, Richter A, Burrows JP, Schroeder WH. Antarctic springtime depletion of atmospheric mercury. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2002; 36:1238-1244. [PMID: 11944675 DOI: 10.1021/es015710z] [Citation(s) in RCA: 106] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Unlike other heavy metals that are inherently associated with atmospheric aerosols, mercury in ambient air exists predominantly in the gaseous elemental form. Because of its prolonged atmospheric residence time, elemental mercury vapor is distributed on a global scale. Recently, Canadian researchers have discovered that total gaseous mercury levels in the lower tropospheric boundary layer in the Canadian Arctic are often significantly depleted during the months after polar sunrise. A possible explanation may involve oxidation of elemental mercury, followed by adsorption and deposition of the oxidized form, leading to an increased input of atmospheric mercury into the Arctic ecosystem. Here we present the first continuous high-time-resolution measurements of total gaseous mercury in the Antarctic covering a 12-month period between January 2000 and January 2001 at the German Antarctic research station Neumayer (70 degrees 39' S, 8 degrees 15' W). We report that mercury depletion events also occur in the Antarctic after polar sunrise and compare our measurements with a data setfrom Alert, Nunavut, Canada. We also present indications that BrO radicals and ozone play a key role in the boundary-layer chemistry during springtime mercury depletion events in the Antarctic troposphere.
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Affiliation(s)
- Ralf Ebinghaus
- Institute for Coastal Research/Physical and Chemical Analysis, GKSS Research Centre Geesthacht, Germany.
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40
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Hara K. Atmospheric inorganic chlorine and bromine species in Arctic boundary layer of the winter/spring. ACTA ACUST UNITED AC 2002. [DOI: 10.1029/2001jd001008] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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41
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Weinbrecht S, Raasch S. High-resolution simulations of the turbulent flow in the vicinity of an Arctic lead. ACTA ACUST UNITED AC 2001. [DOI: 10.1029/2000jc000781] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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42
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Wagner T, Leue C, Wenig M, Pfeilsticker K, Platt U. Spatial and temporal distribution of enhanced boundary layer BrO concentrations measured by the GOME instrument aboard ERS-2. ACTA ACUST UNITED AC 2001. [DOI: 10.1029/2000jd000201] [Citation(s) in RCA: 106] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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43
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Santos CMP, Faria RB, Machuca-Herrera JO, Machado SDP. Equilibrium geometry, vibrational frequencies, and heat of formation of HOBr, HBrO2, and HBrO3 isomers. CAN J CHEM 2001. [DOI: 10.1139/v01-082] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The equilibrium geometries, vibrational frequencies, heat capacity, and heat of formation for compounds of general formula HBrOx were calculated by DFT (BP and pBP methods) with DN* and DN** numerical basis sets. The comparison of our HOBr calculated results with the HOBr experimental values points out that the BP and pBP methods are as good as other ab initio and DFT methods related in the literature employing extended basis sets. The calculated HBrOx total energy and heat of formation values, at 0 and 298.15 K, present the following order: HOBr < HBrO; HOOBr < HOBrO < HBrO2; HOOOBr < HOBrO2 < HOOBrO < HBrO3. The HBrOx heat of formation was calculated using isodesmic and homodesmic reactions and the results show that, in general, the use of these reactions gives similar results.Key words: HOBr, HBrO2, HBrO3, DFT, numerical basis.
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44
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Zheng X, Lee CW, Li YL, Fang WH, Phillips DL. Transient resonance Raman spectroscopy and density functional theory investigation of iso-CHBr2Cl and iso-CCl3Br photoproducts produced following ultraviolet excitation of CHBr2Cl and CCl3Br. J Chem Phys 2001. [DOI: 10.1063/1.1367391] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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45
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Hudson PK, Foster KL, Tolbert MA, George SM, Carlo SR, Grassian VH. HBr Uptake on Ice: Uptake Coefficient, H2O/HBr Hydrate Formation, and H2O Desorption Kinetics. J Phys Chem A 2001. [DOI: 10.1021/jp002700w] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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46
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Kondratyev KY, Varotsos CA. Global tropospheric ozone dynamics. Part I: Tropospheric ozone precursors. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2001; 8:57-62. [PMID: 11370655 DOI: 10.1007/bf02987295] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/16/2023]
Abstract
An overview of the tropospheric ozone changes is presented focussing mainly on the tropospheric ozone precursors. The complexity of the problem is shown through the consideration of a great number of relevant substances, like nitrogen compounds, volatile organic compounds, peroxyacetyl nitrate, hydroxyl radical, carbon monoxide, alkyl nitrates. The up-to-date knowledge on the relevant numerical modelling is presented in Part II.
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Affiliation(s)
- K Y Kondratyev
- Russian Academy of Sciences, Research Centre for Ecological Safety, 18 Korpusnaya Str., 197042 St. Petersburg, Russia
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47
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Koop T, Kapilashrami A, Molina LT, Molina MJ. Phase transitions of sea-salt/water mixtures at low temperatures: Implications for ozone chemistry in the polar marine boundary layer. ACTA ACUST UNITED AC 2000. [DOI: 10.1029/2000jd900413] [Citation(s) in RCA: 177] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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48
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Carpenter LJ, Liss PS. On temperate sources of bromoform and other reactive organic bromine gases. ACTA ACUST UNITED AC 2000. [DOI: 10.1029/2000jd900242] [Citation(s) in RCA: 196] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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49
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Loerting T, Liedl KR. Toward elimination of discrepancies between theory and experiment: the rate constant of the atmospheric conversion of SO3 to H2SO4. Proc Natl Acad Sci U S A 2000; 97:8874-8. [PMID: 10922048 PMCID: PMC16788 DOI: 10.1073/pnas.97.16.8874] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The hydration rate constant of sulfur trioxide to sulfuric acid is shown to depend sensitively on water vapor pressure. In the 1:1 SO3-H2O complex, the rate is predicted to be slower by about 25 orders of magnitude compared with laboratory results [Lovejoy, E. R., Hanson, D. R. & Huey, L. G. (1996) J. Phys. Chem. 100, 19911-19916; Jayne, J. T., Poschl, U., Chen, Y.-m., Dai, D., Molina, L. T., Worsnop, D. R., Kolb, C. E. & Molina, M. J. (1997) J. Phys. Chem. A 101, 10000-10011]. This discrepancy is removed mostly by allowing a second and third water molecule to participate. An asynchronous water-mediated double proton transfer concerted with the nucleophilic attack and a double proton transfer accompanied by a transient H3O+ rotation are predicted to be the fastest reaction mechanisms. Comparison of the predicted negative apparent "activation" energies with the experimental finding indicates that in our atmosphere, different reaction paths involving two and three water molecules are taken in the process of forming sulfate aerosols and consequently acid rain.
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Affiliation(s)
- T Loerting
- Institute of General, Inorganic, and Theoretical Chemistry, University of Innsbruck, Innrain 52a, A-6020 Innsbruck, Austria
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50
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Chaix L, Allanic A, Rossi MJ. Heterogeneous Chemistry of HOBr on Different Types of Ice and on Ice Doped with HCl, HBr, and HNO3 at 175 K < T < 215 K. J Phys Chem A 2000. [DOI: 10.1021/jp001018z] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Affiliation(s)
- L. Chaix
- Laboratoire de Pollution Atmosphérique (LPA), Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - A. Allanic
- Laboratoire de Pollution Atmosphérique (LPA), Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
| | - M. J. Rossi
- Laboratoire de Pollution Atmosphérique (LPA), Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
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