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Wada R, Tonokura K, Koba S, Imamura T, Nakai K, Ushiyama H, Yamashita K, Matsumi Y, Enami S, Seakins PW. Theoretical study on the enthalpies of adduct formation between alkyl iodides and chlorine atoms. Chem Phys Lett 2021. [DOI: 10.1016/j.cplett.2020.138140] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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2
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Foreman ES, Murray C. Kinetics of IO Production in the CH2I + O2 Reaction Studied by Cavity Ring-Down Spectroscopy. J Phys Chem A 2015; 119:8981-90. [DOI: 10.1021/acs.jpca.5b05058] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Elizabeth S. Foreman
- Department
of Chemistry, University of California, Irvine, Irvine, California 92697, United States
| | - Craig Murray
- Department
of Chemistry, University of California, Irvine, Irvine, California 92697, United States
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Sorvajärvi T, Viljanen J, Toivonen J, Marshall P, Glarborg P. Rate constant and thermochemistry for K + O2 + N2 = KO2 + N2. J Phys Chem A 2015; 119:3329-36. [PMID: 25775408 DOI: 10.1021/acs.jpca.5b00755] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The addition reaction of potassium atoms with oxygen has been studied using the collinear photofragmentation and atomic absorption spectroscopy (CPFAAS) method. KCl vapor was photolyzed with 266 nm pulses and the absorbance by K atoms at 766.5 nm was measured at various delay times with a narrow line width diode laser. Experiments were carried out with O2/N2 mixtures at a total pressure of 1 bar, over 748-1323 K. At the lower temperatures single exponential decays of [K] yielded the third-order rate constant for addition, kR1, whereas at higher temperatures equilibration was observed in the form of double exponential decays of [K], which yielded both kR1 and the equilibrium constant for KO2 formation. kR1 can be summarized as 1.07 × 10(-30)(T/1000 K)(-0.733) cm(6) molecule(-2) s(-1). Combination with literature values leads to a recommended kR1 of 5.5 × 10(-26)T(-1.55) exp(-10/T) cm(6) molecule(-2) s(-1) over 250-1320 K, with an error limit of a factor of 1.5. A van't Hoff analysis constrained to fit the computed ΔS298 yields a K-O2 bond dissociation enthalpy of 184.2 ± 4.0 kJ mol(-1) at 298 K and ΔfH298(KO2) = -95.2 ± 4.1 kJ mol(-1). The corresponding D0 is 181.5 ± 4.0 kJ mol(-1). This value compares well with a CCSD(T) extrapolation to the complete basis set limit, with all electrons correlated, of 177.9 kJ mol(-1).
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Affiliation(s)
- Tapio Sorvajärvi
- †Optics Laboratory, Department of Physics, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere, Finland
| | - Jan Viljanen
- †Optics Laboratory, Department of Physics, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere, Finland
| | - Juha Toivonen
- †Optics Laboratory, Department of Physics, Tampere University of Technology, P.O. Box 692, FI-33101 Tampere, Finland
| | - Paul Marshall
- ‡Department of Chemistry and Center for Advanced Scientific Computing and Modeling (CASCaM), University of North Texas, 1155 Union Circle #305070, Denton, Texas 76203-5017, United States
| | - Peter Glarborg
- §Department of Chemical and Biochemical Engineering, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
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Sharma RC, Blitz M, Wada R, Seakins PW. HCl yield and chemical kinetics study of the reaction of Cl atoms with CH3I at the 298K temperature using the infra-red tunable diode laser absorption spectroscopy. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2014; 128:176-182. [PMID: 24667422 DOI: 10.1016/j.saa.2014.02.065] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2013] [Revised: 02/07/2014] [Accepted: 02/14/2014] [Indexed: 06/03/2023]
Abstract
Pulsed ArF excimer laser (193 nm)-CW infrared (IR) tunable diode laser Herriott type absorption spectroscopic technique has been made for the detection of product hydrochloric acid HCl. Absorption spectroscopic technique is used in the reaction chlorine atoms with methyl iodide (Cl+CH3I) to the study of kinetics on reaction Cl+CH3I and the yield of (HCl). The reaction of Cl+CH3I has been studied with the support of the reaction Cl+C4H10 (100% HCl) at temperature 298 K. In the reaction Cl+CH3I, the total pressure of He between 20 and 125 Torr at the constant concentration of [CH3I] 7.0×10(14) molecule cm(-3). In the present work, we estimated adduct formation is very important in the reaction Cl+CH3I and reversible processes as well and CH3I molecule photo-dissociated in the methyl [CH3] radical. The secondary chemistry has been studied as CH3+CH3ICl = product, and CH3I+CH3ICl = product2. The system has been modeled theoretically for secondary chemistry in the present work. The calculated and experimentally HCl yield nearly 65% at the concentration 1.00×10(14) molecule cm(-3) of [CH3I] and 24% at the concentration 4.0×10(15) molecule cm(-3) of [CH3I], at constant concentration 4.85×10(12) molecule cm(-3) of [CH3], and at 7.3×10(12) molecule cm(-3) of [Cl]. The pressure dependent also studied product of HCl at the constant [CH3], [Cl] and [CH3I]. The experimental results are also very good matching with the modelling work at the reaction CH3+CH3ICl = product (k = (2.75±0.35)×10(-10) s(-1)) and CH3I+CH3ICl = product2 (k = 1.90±0.15)×10(-12) s(-1). The rate coefficients of the reaction CH3+CH3ICl and CH3I+CH3ICl has been made in the present work. The experimental results has been studied by two method (1) phase locked and (2) burst mode.
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Affiliation(s)
- R C Sharma
- Lasers Laboratory, Department of Chemistry, The University of Leeds, Leeds LS 2 9JT, United Kingdom.
| | - M Blitz
- Lasers Laboratory, Department of Chemistry, The University of Leeds, Leeds LS 2 9JT, United Kingdom
| | - R Wada
- Lasers Laboratory, Department of Chemistry, The University of Leeds, Leeds LS 2 9JT, United Kingdom
| | - P W Seakins
- Lasers Laboratory, Department of Chemistry, The University of Leeds, Leeds LS 2 9JT, United Kingdom
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5
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Saiz-Lopez A, Plane JMC, Baker AR, Carpenter LJ, von Glasow R, Gómez Martín JC, McFiggans G, Saunders RW. Atmospheric Chemistry of Iodine. Chem Rev 2011; 112:1773-804. [DOI: 10.1021/cr200029u] [Citation(s) in RCA: 383] [Impact Index Per Article: 29.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Alfonso Saiz-Lopez
- Laboratory for Atmospheric and Climate Science (CIAC), CSIC, Toledo, Spain
| | - John M. C. Plane
- School of Chemistry, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - Alex R. Baker
- School of Environmental Sciences, University of East Anglia, Norwich NR4 7TJ, United Kingdom
| | - Lucy J. Carpenter
- Department of Chemistry, University of York, Heslington, York YO10 5DD, United Kingdom
| | - Roland von Glasow
- School of Environmental Sciences, University of East Anglia, Norwich NR4 7TJ, United Kingdom
| | | | - Gordon McFiggans
- School of Earth, Atmospheric & Environmental Sciences, University of Manchester, Manchester, M13 9PL, United Kingdom
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Laine PL, Sohn YS, Nicovich JM, Mckee ML, Wine PH. Kinetics of elementary steps in the reaction of atomic bromine with 2,3-dimethyl-2-butene under atmospheric conditions. INT J CHEM KINET 2011. [DOI: 10.1002/kin.20608] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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7
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Larin IK, Spasskii AI, Trofimova EM, Turkin LE. Formation of iodine atoms in the heterogeneous reaction between chlorine and iodomethane. KINETICS AND CATALYSIS 2010. [DOI: 10.1134/s0023158410030031] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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8
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Kinetic study of the reaction of chlorine atoms with bromomethane and D-bromomethane in the gas phase. Chem Phys Lett 2010. [DOI: 10.1016/j.cplett.2009.12.076] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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9
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Wada R, Sharma RC, Blitz MA, Seakins PW. Studies on the Cl + C2H5I reaction; site specific abstraction reactions and thermodynamics of adduct formation studied by observation of HCL product. Phys Chem Chem Phys 2009; 11:10417-26. [PMID: 19890528 DOI: 10.1039/b907793f] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Affiliation(s)
- R Wada
- School of Chemistry, University of Leeds, Leeds, UK LS2 9JT
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Marinkovic M, Gruber-Stadler M, Nicovich JM, Soller R, Mülhäuser M, Wine PH, Bache-Andreassen L, Nielsen CJ. Experimental and Theoretical Study of the Carbon-13 and Deuterium Kinetic Isotope Effects in the Cl and OH Reactions of CH3F. J Phys Chem A 2008; 112:12416-29. [PMID: 18989948 DOI: 10.1021/jp807609d] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Marina Marinkovic
- Centre for Theoretical and Computational Chemistry, Department of Chemistry, University of Oslo, P.O. Box. 1033, Blindern 0315 Oslo, Norway, Studiengang Umwelt-, Verfahrens- & Biotechnik, MCI—Management Center Innsbruck Internationale Fachhochschulgesellschaft mbH, Egger-Lienz-Strasse 120, A-6020 Innsbruck, Austria, and School of Chemistry and Biochemistry and School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, Georgia 30332
| | - Margret Gruber-Stadler
- Centre for Theoretical and Computational Chemistry, Department of Chemistry, University of Oslo, P.O. Box. 1033, Blindern 0315 Oslo, Norway, Studiengang Umwelt-, Verfahrens- & Biotechnik, MCI—Management Center Innsbruck Internationale Fachhochschulgesellschaft mbH, Egger-Lienz-Strasse 120, A-6020 Innsbruck, Austria, and School of Chemistry and Biochemistry and School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, Georgia 30332
| | - J. Michael Nicovich
- Centre for Theoretical and Computational Chemistry, Department of Chemistry, University of Oslo, P.O. Box. 1033, Blindern 0315 Oslo, Norway, Studiengang Umwelt-, Verfahrens- & Biotechnik, MCI—Management Center Innsbruck Internationale Fachhochschulgesellschaft mbH, Egger-Lienz-Strasse 120, A-6020 Innsbruck, Austria, and School of Chemistry and Biochemistry and School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, Georgia 30332
| | - Raenell Soller
- Centre for Theoretical and Computational Chemistry, Department of Chemistry, University of Oslo, P.O. Box. 1033, Blindern 0315 Oslo, Norway, Studiengang Umwelt-, Verfahrens- & Biotechnik, MCI—Management Center Innsbruck Internationale Fachhochschulgesellschaft mbH, Egger-Lienz-Strasse 120, A-6020 Innsbruck, Austria, and School of Chemistry and Biochemistry and School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, Georgia 30332
| | - Max Mülhäuser
- Centre for Theoretical and Computational Chemistry, Department of Chemistry, University of Oslo, P.O. Box. 1033, Blindern 0315 Oslo, Norway, Studiengang Umwelt-, Verfahrens- & Biotechnik, MCI—Management Center Innsbruck Internationale Fachhochschulgesellschaft mbH, Egger-Lienz-Strasse 120, A-6020 Innsbruck, Austria, and School of Chemistry and Biochemistry and School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, Georgia 30332
| | - Paul H. Wine
- Centre for Theoretical and Computational Chemistry, Department of Chemistry, University of Oslo, P.O. Box. 1033, Blindern 0315 Oslo, Norway, Studiengang Umwelt-, Verfahrens- & Biotechnik, MCI—Management Center Innsbruck Internationale Fachhochschulgesellschaft mbH, Egger-Lienz-Strasse 120, A-6020 Innsbruck, Austria, and School of Chemistry and Biochemistry and School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, Georgia 30332
| | - Lihn Bache-Andreassen
- Centre for Theoretical and Computational Chemistry, Department of Chemistry, University of Oslo, P.O. Box. 1033, Blindern 0315 Oslo, Norway, Studiengang Umwelt-, Verfahrens- & Biotechnik, MCI—Management Center Innsbruck Internationale Fachhochschulgesellschaft mbH, Egger-Lienz-Strasse 120, A-6020 Innsbruck, Austria, and School of Chemistry and Biochemistry and School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, Georgia 30332
| | - Claus J. Nielsen
- Centre for Theoretical and Computational Chemistry, Department of Chemistry, University of Oslo, P.O. Box. 1033, Blindern 0315 Oslo, Norway, Studiengang Umwelt-, Verfahrens- & Biotechnik, MCI—Management Center Innsbruck Internationale Fachhochschulgesellschaft mbH, Egger-Lienz-Strasse 120, A-6020 Innsbruck, Austria, and School of Chemistry and Biochemistry and School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, Georgia 30332
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11
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Enami S, Sakamoto Y, Yamanaka T, Hashimoto S, Kawasaki M, Tonokura K, Tachikawa H. Reaction Mechanisms of IO Radical Formation from the Reaction of CH3I with Cl Atom in the Presence of O2. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2008. [DOI: 10.1246/bcsj.81.1250] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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12
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Gravestock TJ, Blitz MA, Heard DE. A Kinetic and Spectroscopic Study of the CH3I−Cl and ICH2I−Cl Adducts. J Phys Chem A 2008; 112:9544-54. [DOI: 10.1021/jp800372c] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Affiliation(s)
| | - M. A. Blitz
- School of Chemistry, University of Leeds, Leeds, LS2 9JT, U.K
| | - D. E. Heard
- School of Chemistry, University of Leeds, Leeds, LS2 9JT, U.K
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Dookwah-Roberts V, Nicovich JM, Wine PH. Spectroscopic and Kinetic Study of the Gas-Phase CH3I−Cl and C2H5I−Cl Adducts. J Phys Chem A 2008; 112:9535-43. [PMID: 18517179 DOI: 10.1021/jp800270r] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- V. Dookwah-Roberts
- School of Earth and Atmospheric Sciences, School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332
| | - J. M. Nicovich
- School of Earth and Atmospheric Sciences, School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332
| | - P. H. Wine
- School of Earth and Atmospheric Sciences, School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332
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Stefanopoulos VG, Papadimitriou VC, Lazarou YG, Papagiannakopoulos P. Absolute Rate Coefficient Determination and Reaction Mechanism Investigation for the Reaction of Cl Atoms with CH2I2and the Oxidation Mechanism of CH2I Radicals. J Phys Chem A 2008; 112:1526-35. [DOI: 10.1021/jp7096789] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Vassileios G. Stefanopoulos
- Laboratory of Photochemistry and Kinetics, Department of Chemistry, University of Crete, Heraklion 710 03, Crete, Greece
| | - Vassileios C. Papadimitriou
- Laboratory of Photochemistry and Kinetics, Department of Chemistry, University of Crete, Heraklion 710 03, Crete, Greece
| | - Yannis G. Lazarou
- Laboratory of Photochemistry and Kinetics, Department of Chemistry, University of Crete, Heraklion 710 03, Crete, Greece
| | - Panos Papagiannakopoulos
- Laboratory of Photochemistry and Kinetics, Department of Chemistry, University of Crete, Heraklion 710 03, Crete, Greece
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15
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Gao Y, Fessel K, McLeod C, Marshall P. A kinetic study of the reaction of atomic hydrogen with iodobenzene. Chem Phys Lett 2008. [DOI: 10.1016/j.cplett.2007.11.061] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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16
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Zhao Z, Huskey DT, Nicovich JM, Wine PH. Temperature-dependent kinetics study of the gas-phase reactions of atomic chlorine with acetone, 2-butanone, and 3-pentanone. INT J CHEM KINET 2008. [DOI: 10.1002/kin.20321] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
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17
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Irikura KK, Francisco JS. Competition between hydrogen abstraction and halogen displacement in the reaction of Br with CH3I, CH3Br, and CH3Cl. J Phys Chem A 2007; 111:6852-9. [PMID: 17580833 DOI: 10.1021/jp071314c] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Sudden ozone depletion events in the marine boundary layer are associated with jumps in the CH3Br mixing ratio, but current models of atmospheric chemistry explain neither the ozone depletion nor the CH3Br spikes. We have used ab initio theory to predict the forward and reverse rate constants for the competing hydrogen abstraction and homolytic substitution (SH2) channels of the title reactions. Including the spin-orbit stabilization of the transition structures increases the rate constants by factors between 1.3 and 49. For the atmospherically relevant case of CH3I, our findings suggest that the hydrogen abstraction and homolytic substitution reactions are competitive. The predicted branching fraction to CH3Br is about 13%.
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Affiliation(s)
- Karl K Irikura
- Physical and Chemical Properties Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8380, USA.
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18
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Spectroscopy and kinetics of the gas phase addition complex of atomic chlorine with dimethyl sulfoxide. J Photochem Photobiol A Chem 2007. [DOI: 10.1016/j.jphotochem.2006.08.020] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Zhao Z, Huskey DT, Olsen KJ, Nicovich JM, McKee ML, Wine PH. Kinetics, mechanism, and thermochemistry of the gas-phase reaction of atomic chlorine with pyridine. Phys Chem Chem Phys 2007; 9:4383-94. [PMID: 17687485 DOI: 10.1039/b707017a] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A laser flash photolysis-resonance fluorescence technique has been employed to study the kinetics of the reaction of atomic chlorine with pyridine (C(5)H(5)N) as a function of temperature (215-435 K) and pressure (25-250 Torr) in nitrogen bath gas. At T> or = 299 K, measured rate coefficients are pressure independent and a significant H/D kinetic isotope effect is observed, suggesting that hydrogen abstraction is the dominant reaction pathway. The following Arrhenius expression adequately describes all kinetic data at 299-435 K for C(5)H(5)N: k(1a) = (2.08 +/- 0.47) x 10(-11) exp[-(1410 +/- 80)/T] cm(3) molecule(-1) s(-1) (uncertainties are 2sigma, precision only). At 216 K < or =T< or = 270 K, measured rate coefficients are pressure dependent and are much faster than computed from the above Arrhenius expression for the H-abstraction pathway, suggesting that the dominant reaction pathway at low temperature is formation of a stable adduct. Over the ranges of temperature, pressure, and pyridine concentration investigated, the adduct undergoes dissociation on the time scale of our experiments (10(-5)-10(-2) s) and establishes an equilibrium with Cl and pyridine. Equilibrium constants for adduct formation and dissociation are determined from the forward and reverse rate coefficients. Second- and third-law analyses of the equilibrium data lead to the following thermochemical parameters for the addition reaction: Delta(r)H = -47.2 +/- 2.8 kJ mol(-1), Delta(r)H = -46.7 +/- 3.2 kJ mol(-1), and Delta(r)S = -98.7 +/- 6.5 J mol(-1) K(-1). The enthalpy changes derived from our data are in good agreement with ab initio calculations reported in the literature (which suggest that the adduct structure is planar and involves formation of an N-Cl sigma-bond). In conjunction with the well-known heats of formation of atomic chlorine and pyridine, the above Delta(r)H values lead to the following heats of formation for C(5)H(5)N-Cl at 298 K and 0 K: Delta(f)H = 216.0 +/- 4.1 kJ mol(-1), Delta(f)H = 233.4 +/- 4.6 kJ mol(-1). Addition of Cl to pyridine could be an important atmospheric loss process for pyridine if the C(5)H(5)N-Cl product is chemically degraded by processes that do not regenerate pyridine with high yield.
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Affiliation(s)
- Z Zhao
- School of Earth & Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA 30332-0340, USA
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Nicovich JM, Parthasarathy S, Pope FD, Pegus AT, McKee ML, Wine PH. Kinetics, Mechanism, and Thermochemistry of the Gas Phase Reaction of Atomic Chlorine with Dimethyl Sulfoxide. J Phys Chem A 2006; 110:6874-85. [PMID: 16722703 DOI: 10.1021/jp0567467] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A laser flash photolysis-resonance fluorescence technique has been employed to study the kinetics of the reaction of chlorine atoms with dimethyl sulfoxide (CH3S(O)CH3; DMSO) as a function of temperature (270-571 K) and pressure (5-500 Torr) in nitrogen bath gas. At T = 296 K and P > or = 5 Torr, measured rate coefficients increase with increasing pressure. Combining our data with literature values for low-pressure rate coefficients (0.5-3 Torr He) leads to a rate coefficient for the pressure independent H-transfer channel of k1a = 1.45 x 10(-11) cm3 molecule(-1) s(-1) and the following falloff parameters for the pressure-dependent addition channel in N2 bath gas: k(1b,0) = 2.53 x 10(-28) cm6 molecule(-2) s(-1); k(1b,infinity) = 1.17 x 10(-10) cm3 molecule(-1) s(-1), F(c) = 0.503. At the 95% confidence level, both k1a and k1b(P) have estimated accuracies of +/-30%. At T > 430 K, where adduct decomposition is fast enough that only the H-transfer pathway is important, measured rate coefficients are independent of pressure (30-100 Torr N2) and increase with increasing temperature. The following Arrhenius expression adequately describes the temperature dependence of the rate coefficients measured at over the range 438-571 K: k1a = (4.6 +/- 0.4) x 10(-11) exp[-(472 +/- 40)/T) cm3 molecule(-1) s(-1) (uncertainties are 2sigma, precision only). When our data at T > 430 K are combined with values for k1a at temperatures of 273-335 K that are obtained by correcting reported low-pressure rate coefficients from discharge flow studies to remove the contribution from the pressure-dependent channel, the following modified Arrhenius expression best describes the derived temperature dependence: k1a = 1.34 x 10(-15)T(1.40) exp(+383/T) cm3 molecule(-1) s(-1) (273 K < or = T < or = 571 K). At temperatures around 330 K, reversible addition is observed, thus allowing equilibrium constants for Cl-DMSO formation and dissociation to be determined. A third-law analysis of the equilibrium data using structural information obtained from electronic structure calculations leads to the following thermochemical parameters for the association reaction: delta(r)H(o)298 = -72.8 +/- 2.9 kJ mol(-1), deltaH(o)0 = -71.5 +/- 3.3 kJ mol(-1), and delta(r)S(o)298 = -110.6 +/- 4.0 J K(-1) mol(-1). In conjunction with standard enthalpies of formation of Cl and DMSO taken from the literature, the above values for delta(r)H(o) lead to the following values for the standard enthalpy of formation of Cl-DMSO: delta(f)H(o)298 = -102.7 +/- 4.9 kJ mol(-1) and delta(r)H(o)0 = -84.4 +/- 5.8 kJ mol(-1). Uncertainties in the above thermochemical parameters represent estimated accuracy at the 95% confidence level. In agreement with one published theoretical study, electronic structure calculations using density functional theory and G3B3 theory reproduce the experimental adduct bond strength quite well.
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Affiliation(s)
- J M Nicovich
- School of Chemistry & Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, USA
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Orlando JJ, Piety CA, Nicovich JM, McKee ML, Wine PH. Rates and Mechanisms for the Reactions of Chlorine Atoms with Iodoethane and 2-Iodopropane. J Phys Chem A 2005; 109:6659-75. [PMID: 16834018 DOI: 10.1021/jp051715x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The reaction of Cl atoms with iodoethane has been studied via a combination of laser flash photolysis/resonance fluorescence (LFP-RF), environmental chamber/Fourier transform (FT)IR, and quantum chemical techniques. Above 330 K, the flash photolysis data indicate that the reaction proceeds predominantly via hydrogen abstraction. The following Arrhenius expressions (in units of cm3 molecule(-1) s(-1)) apply over the temperature range 334-434 K for reaction of Cl with CH3CH2I (k4(H)) and CD3CD2I (k4(D)): k4(H) = (6.53 +/- 3.40) x 10(-11) exp[-(428 +/- 206)/T] and k4(D) = (2.21 +/- 0.44) x 10(-11) exp[-(317 +/- 76)/T]. At room temperature and below, the reaction proceeds both via hydrogen abstraction and via reversible formation of an iodoethane/Cl adduct. Analysis of the LFP-RF data yields a binding enthalpy (0 K) for CD3CD2I x Cl of 57 +/- 10 kJ mol(-1). Calculations using density functional theory show that the adduct is characterized by a C-I-Cl bond angle of 84.5 degrees; theoretical binding enthalpies of 38.2 kJ/mol, G2'[ECP(S)], and 59.0 kJ mol(-1), B3LYP/ECP, are reasonably consistent with the experimentally derived result. Product studies conducted in the environmental chamber show that hydrogen abstraction from both the -CH2I and -CH3 groups occur to a significant extent and also provide evidence for a reaction of the CH3CH2I x Cl adduct with CH3CH2I, leading to CH3CH2Cl formation. Complementary environmental chamber studies of the reaction of Cl atoms with 2-iodopropane, CH3CHICH3, are also presented. As determined by relative rate methods, the reaction proceeds with an effective rate coefficient, k6, of (5.0 +/- 0.6) x 10(-11) cm3 molecule(-1) s(-1) at 298 K. Product studies indicate that this reaction also occurs via two abstraction channels (from the CH3 groups and from the -CHI- group) and via reversible adduct formation.
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Affiliation(s)
- John J Orlando
- Atmospheric Chemistry Division, National Center for Atmospheric Research, Boulder, Colorado 80305, USA
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Enami S, Yamanaka T, Hashimoto S, Kawasaki M, Tonokura K. Direct Observation of Adduct Formation of Alkyl and Aromatic Iodides with Cl Atoms Using Cavity Ring-Down Spectroscopy. J Phys Chem A 2005; 109:6066-70. [PMID: 16833942 DOI: 10.1021/jp0520188] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The reactions of Cl atoms with RI (R = n-C3H7, n-C4H9, cyclo-C6H11, C6H5, C6F5, and p-CH3C6H4) have been studied using cavity ring-down spectroscopy at a temperature range of 233-313 K and at 100 Torr total pressure of N2 diluent. Visible absorption spectra of the RI-Cl adducts were recorded at 440-520 nm at 263 K. The yields of the adducts were temperature-dependent. There was no discernible reaction of the adducts in the presence of 100 Torr of O2 at 263 K. Theoretical calculations were performed for C4H9I-Cl and C6H5I-Cl for quantitative explanation of the absorption spectra and the strength of the I-Cl bonds in the charge-transfer complexes. Evidence for the adduct formation following the reaction of Cl with C6H5Br was sought but not found at 440 and 520 nm.
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Affiliation(s)
- Shinichi Enami
- Department of Molecular Engineering and Graduate School of Global Environmental Studies, Kyoto University, Kyoto 615-8510, Japan
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Enami S, Hashimoto S, Kawasaki M, Nakano Y, Ishiwata T, Tonokura K, Wallington TJ. Observation of Adducts in the Reaction of Cl Atoms with XCH2I (X = H, CH3, Cl, Br, I) Using Cavity Ring-Down Spectroscopy. J Phys Chem A 2005; 109:1587-93. [PMID: 16833481 DOI: 10.1021/jp047297y] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The reactions of Cl atoms with XCH2I (X = H, CH3, Cl, Br, I) have been studied using cavity ring-down spectroscopy in 25-125 Torr total pressure of N2 diluent at 250 K. Formation of the XCH2I-Cl adduct is the dominant channel in all reactions. The visible absorption spectrum of the XCH2I-Cl adduct was recorded at 405-632 nm. Absorption cross-sections at 435 nm are as follows (in units of 10(-18) cm2 molecule(-1)): 12 for CH3I, 21 for CH3CH2I, 3.7 for CH2ICl, 7.1 for CH2IBr, and 3.7 for CH2I2. Rate constants for the reaction of Cl with CH3I were determined from rise profiles of the CH3I-Cl adduct. k(Cl + CH3I) increases from (0.4 +/- 0.1) x 10(-11) at 25 Torr to (2.0 +/- 0.3) x 10(-11) cm3 molecule(-1) s(-1) at 125 Torr of N2 diluent. There is no discernible reaction of the CH3I-Cl adduct with 5-10 Torr of O2. Evidence for the formation of an adduct following the reaction of Cl atoms with CF3I and CH3Br was sought but not found. Absorption attributable to the formation of the XCH2I-Cl adduct following the reaction of Cl atoms with XCH2I (X = H, CH3, Br, I) was measured as a function of temperature over the range 250-320 K.
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Affiliation(s)
- Shinichi Enami
- Department of Molecular Engineering and Graduate School of Global Environmental Studies, Kyoto University, Kyoto 615-8510, Japan
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Murray C, Orr-Ewing * AJ. The dynamics of chlorine-atom reactions with polyatomic organic molecules. INT REV PHYS CHEM 2004. [DOI: 10.1080/01442350412331329166] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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26
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27
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Yamada T, El-Sinawi A, Siraj M, Taylor PH, Peng J, Hu X, Marshall P. Rate Coefficients and Mechanistic Analysis for the Reaction of Hydroxyl Radicals with 1,1-Dichloroethylene and trans-1,2-Dichloroethylene over an Extended Temperature Range. J Phys Chem A 2001. [DOI: 10.1021/jp0109067] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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28
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Kambanis KG, Argyris DY, Lazarou YG, Papagiannakopoulos P. Absolute Reaction Rate of Chlorine Atoms with Chloroiodomethane. J Phys Chem A 1999. [DOI: 10.1021/jp984193c] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | - Dimitris Y. Argyris
- Department of Chemistry, University of Crete, Heraklion 71409, Crete, Greece
| | - Yannis G. Lazarou
- Department of Chemistry, University of Crete, Heraklion 71409, Crete, Greece
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Bilde M, Wallington TJ. Atmospheric Chemistry of CH3I: Reaction with Atomic Chlorine at 1−700 Torr Total Pressure and 295 K. J Phys Chem A 1998. [DOI: 10.1021/jp973303x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Merete Bilde
- Atmospheric Chemistry, Building 313, Plant Biology and Biogeochemistry Department, Risø National Laboratory, DK-4000 Roskilde, Denmark
| | - Timothy J. Wallington
- Ford Research Laboratory, SRL-3083, Ford Motor Company, P.O. Box 2053, Dearborn, Michigan 48121-2053
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