1
|
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]
|
2
|
Burkholder JB, Cox RA, Ravishankara AR. Atmospheric degradation of ozone depleting substances, their substitutes, and related species. Chem Rev 2015; 115:3704-59. [PMID: 25893463 DOI: 10.1021/cr5006759] [Citation(s) in RCA: 87] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- James B Burkholder
- †Chemical Sciences Division, Earth System Laboratory, National Oceanic and Atmospheric Administration, 325 Broadway, Boulder, Colorado 80305, United States
| | - R A Cox
- ‡Centre for Atmospheric Science, Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EP, United Kingdom
| | - A R Ravishankara
- §Departments of Chemistry and Atmospheric Science, Colorado State University, 1872 Campus Delivery, Fort Collins, Colorado 80523, United States
| |
Collapse
|
3
|
Nicovich JM, Mazumder S, Laine PL, Wine PH, Tang Y, Bunkan AJC, Nielsen CJ. An experimental and theoretical study of the gas phase kinetics of atomic chlorine reactions with CH3NH2, (CH3)2NH, and (CH3)3N. Phys Chem Chem Phys 2015; 17:911-7. [DOI: 10.1039/c4cp03801k] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The first kinetic data for the gas phase reactions of amines with chlorine atoms.
Collapse
Affiliation(s)
- J. M. Nicovich
- School of Chemistry & Biochemistry
- Georgia Institute of Technology
- Atlanta
- USA
| | - S. Mazumder
- School of Chemistry & Biochemistry
- Georgia Institute of Technology
- Atlanta
- USA
| | - P. L. Laine
- School of Earth & Atmospheric Sciences
- Georgia Institute of Technology
- Atlanta
- USA
| | - P. H. Wine
- School of Chemistry & Biochemistry
- Georgia Institute of Technology
- Atlanta
- USA
- School of Earth & Atmospheric Sciences
| | - Y. Tang
- School of Environmental and Municipal Engineering
- Qingdao Technological University
- 266033 Qingdao
- P. R. China
| | - A. J. C. Bunkan
- Centre for Theoretical Computational Chemistry
- Department of Chemistry
- University of Oslo
- 0316 Oslo
- Norway
| | - C. J. Nielsen
- Centre for Theoretical Computational Chemistry
- Department of Chemistry
- University of Oslo
- 0316 Oslo
- Norway
| |
Collapse
|
4
|
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.
Collapse
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
| |
Collapse
|
5
|
Sarzyński DS, Gola AA, Brudnik K, Berkowski R, Jodkowski JT. Kinetic study of the reactions of chlorine atoms with fluoroethane and d-fluoroethane in the gas phase. Chem Phys Lett 2013. [DOI: 10.1016/j.cplett.2013.07.016] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
6
|
Valero R, Truhlar DG. Photochemistry in a dense manifold of electronic states: Photodissociation of CH2ClBr. J Chem Phys 2012; 137:22A539. [DOI: 10.1063/1.4747704] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
|
7
|
Zhang S, Strekowski RS, Monod A, Bosland L, Zetzsch C. Temperature-Dependent Kinetics Study of the Reactions of OH with C2H5I, n-C3H7I, and iso-C3H7I. J Phys Chem A 2012; 116:9497-506. [DOI: 10.1021/jp300575f] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Shaoliang Zhang
- Laboratoire Chimie Environment, Aix-Marseille Université, 13331 Marseille cedex
03, France,
- Institut de
Radioprotection
et de Sûreté Nucléaire, DPAM/SEMIC/LETR, Centre de Cadarache, 13115 Saint Paul les Durance cedex,
France
| | - Rafal S. Strekowski
- Laboratoire Chimie Environment, Aix-Marseille Université, 13331 Marseille cedex
03, France,
- CNRS, FRE 3416, 13331 Marseille cedex 03, France
| | - Anne Monod
- Laboratoire Chimie Environment, Aix-Marseille Université, 13331 Marseille cedex
03, France,
- CNRS, FRE 3416, 13331 Marseille cedex 03, France
| | - Loïc Bosland
- Institut de
Radioprotection
et de Sûreté Nucléaire, DPAM/SEMIC/LETR, Centre de Cadarache, 13115 Saint Paul les Durance cedex,
France
| | - Cornelius Zetzsch
- Atmospheric Chemistry Research
Laboratory, BAYCEER, University of Bayreuth, Dr. Hans-Frisch-Strasse 1-3, D-95448 Bayreuth, Germany
| |
Collapse
|
8
|
Nakano Y, Hosho Y, Sadamori K, Ishiwata T. Determination of the rate constant of the reaction of NO3 with C2H5I using time-resolved cavity ring-down spectroscopy. Chem Phys Lett 2012. [DOI: 10.1016/j.cplett.2012.03.040] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
9
|
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
| | | |
Collapse
|
10
|
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]
|
11
|
Kinetic study of the reaction of chlorine atoms with bromoethane and D-bromoethane in the gas phase. Chem Phys Lett 2011. [DOI: 10.1016/j.cplett.2011.04.082] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
|
12
|
Jia XJ, Liu YJ, Sun JY, Sun H, Wang F, Su ZM, Pan XM, Wang RS. Computational studies on the mechanism and kinetics of Cl reaction with C2H5I. J Comput Chem 2010; 31:2263-72. [PMID: 20575010 DOI: 10.1002/jcc.21516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The dual-level direct kinetics method has been used to investigate the multichannel reactions of C(2)H(5)I + Cl. Three hydrogen abstraction channels and one displacement process are found for the title reaction. The calculation indicates that the hydrogen abstraction from -CH(2)- group is the dominant reaction channel, and the displacement process may be negligible because of the high barrier. The rate constants for individual reaction channels are calculated by the improved canonical variational transition-state theory with small-curvature tunneling correction over the temperature range of 220-1500 K. Our results show that the tunneling correction plays an important role in the rate constant calculation in the low-temperature range. Agreement between the calculated and experimental data available is good. The Arrhenius expression k(T) = 2.33 x 10(-16) T(1.83) exp(-185.01/T) over a wide temperature range is obtained. Furthermore, the kinetic isotope effects for the reaction C(2)H(5)I + Cl are estimated so as to provide theoretical estimation for future laboratory investigation.
Collapse
Affiliation(s)
- Xiu-Juan Jia
- Faculty of Chemistry, Institute of Functional Material Chemistry, Northeast Normal University, Changchun 130024, People's Republic of China
| | | | | | | | | | | | | | | |
Collapse
|
13
|
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
| | | | | | | |
Collapse
|
14
|
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]
|
15
|
Uc VH, Alvarez-Idaboy JR, Galano A, Vivier-Bunge A. Theoretical Explanation of Nonexponential OH Decay in Reactions with Benzene and Toluene under Pseudo-First-Order Conditions. J Phys Chem A 2008; 112:7608-15. [DOI: 10.1021/jp8026258] [Citation(s) in RCA: 49] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Víctor Hugo Uc
- Departamento de Química, Universidad Autónoma Metropolitana, Iztapalapa, México D.F., 09340 México, and Facultad de Química, Departamento de Física y Química Teórica, Universidad Nacional Autónoma de México, México D.F., 04510 México
| | - J. Raúl Alvarez-Idaboy
- Departamento de Química, Universidad Autónoma Metropolitana, Iztapalapa, México D.F., 09340 México, and Facultad de Química, Departamento de Física y Química Teórica, Universidad Nacional Autónoma de México, México D.F., 04510 México
| | - Annia Galano
- Departamento de Química, Universidad Autónoma Metropolitana, Iztapalapa, México D.F., 09340 México, and Facultad de Química, Departamento de Física y Química Teórica, Universidad Nacional Autónoma de México, México D.F., 04510 México
| | - Annik Vivier-Bunge
- Departamento de Química, Universidad Autónoma Metropolitana, Iztapalapa, México D.F., 09340 México, and Facultad de Química, Departamento de Física y Química Teórica, Universidad Nacional Autónoma de México, México D.F., 04510 México
| |
Collapse
|
16
|
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
| |
Collapse
|
17
|
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
| |
Collapse
|
18
|
Rosado-Reyes CM, Martínez-Avilés M, Francisco JS. Computational Study of the Reaction of n-Bromopropane with OH Radicals and Cl Atoms. ADVANCES IN QUANTUM CHEMISTRY 2008. [DOI: 10.1016/s0065-3276(07)00211-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
19
|
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]
|
20
|
Formation of the iodine monoxide radical from gas-phase reactions of iodoalkyl radicals with molecular oxygen. Chem Phys Lett 2007. [DOI: 10.1016/j.cplett.2007.08.025] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
21
|
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%.
Collapse
Affiliation(s)
- Karl K Irikura
- Physical and Chemical Properties Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8380, USA.
| | | |
Collapse
|
22
|
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]
|
23
|
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.
Collapse
Affiliation(s)
- Z Zhao
- School of Earth & Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA 30332-0340, USA
| | | | | | | | | | | |
Collapse
|
24
|
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.
Collapse
Affiliation(s)
- J M Nicovich
- School of Chemistry & Biochemistry, Georgia Institute of Technology, Atlanta, Georgia 30332-0400, USA
| | | | | | | | | | | |
Collapse
|