1
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Roman MJ, Knight AG, Moon DR, Lane PD, Costen ML, McKendrick KG. Distinguishing Mechanisms for Reactive Uptake at Liquid Surfaces via Angular Distributions of Inelastically Scattered Molecules. J Phys Chem A 2024; 128:5166-5174. [PMID: 38915192 PMCID: PMC11229065 DOI: 10.1021/acs.jpca.4c02917] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/26/2024]
Abstract
Angular distributions of OH inelastically scattered from the surfaces of the reactive hydrocarbon liquids squalane (fully saturated) and squalene (partially unsaturated) have been measured. A pulsed, rotationally cold molecular beam (Ei = 35 kJ mol-1) of OH was scattered from refreshed liquid surfaces in a vacuum. Spatially and temporally resolved OH number densities were measured by pulsed, planar laser-induced fluorescence. Results are compared with those for the inert liquid perfluoropolyether. The clearly asymmetric distributions for 45° incidence add to the weight of evidence for predominantly impulsive scattering from all three liquids. However, we propose that significant differences in their shapes may be diagnostic of contrasting reaction mechanisms. Direct, near-specular trajectories survive preferentially on squalene, consistent with an addition mechanism removing those at more backward angles. This trend is reversed for squalane, as expected for direct abstraction. The results reinforce the need to consider the effects of composition-dependent contributions from different reaction mechanisms in the modeling of OH-aging of atmospheric aerosol particles.
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Affiliation(s)
- Maksymilian J Roman
- Institute of Chemical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, U.K
| | - Adam G Knight
- Institute of Chemical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, U.K
| | - Daniel R Moon
- Institute of Chemical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, U.K
| | - Paul D Lane
- Institute of Chemical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, U.K
| | - Matthew L Costen
- Institute of Chemical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, U.K
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2
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Cardona AL, Teruel M, Ventura ON. Unexpected high yield of acrolein underlies the importance of the hydrogen-abstraction mechanism in photooxidation of allyl methyl sulfide (AMS). CHEMOSPHERE 2024; 354:141693. [PMID: 38508461 DOI: 10.1016/j.chemosphere.2024.141693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Revised: 03/09/2024] [Accepted: 03/11/2024] [Indexed: 03/22/2024]
Abstract
This work explores theoretically the gas phase oxidation of allyl methyl sulfide (AMS, H2CCHCH2SCH3) initiated by •OH radicals, focusing on the H-abstraction pathway at the M06-2X-D3/aug-cc-pVTZ and MN15/aug-cc-pVTZ levels of theory (m06Tz and mn15Tz). The formation of a prereactive complex (PRC) is involved in H-abstraction processes with two potential directions of approach for the OH radical, denoted as "α" and "β". The PRCs, demonstrate increased reactivity, primarily due to the interaction between the sulfur atoms and the hydroxyl hydrogen. A scheme for the H-abstraction mechanism that supports the experimentally identified products and predicts the formation of some S-containing low volatility products is proposed. The comparison of the potential energy surface (PES) between the double bond addition and H-abstraction paths in the AMS molecule shows that at the m06Tz level of theory, the H-abstraction on C3 and the addition to C1 have nearly the same profile of energy, while at the mn15Tz level, the minimum energy channel is the addition to C1. The theoretical rate coefficient for each reaction channel was calculated, considering the formation of a PRC prior to reaching the transition state of each channel and assuming thermal equilibrium between reactants and the PRC. The rate constants were calculated in a multi-TS/multi-conformer way at the SVECV-f12/m06Tz and SVECV-f12/mn15Tz levels of theory. The SVECV-f12 method is consistent in its predictions in both systems and exhibits only minor deviations from the experimental rate constants. Despite some specific differences due to the DFT method supporting the SVECV-f12 calculations, both methodologies predict a significant H-abstraction contribution in the AMS + OH gas phase reaction, which explains the high formation yield for acrolein determined experimentally.
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Affiliation(s)
- Alejandro L Cardona
- Computational Chemistry and Biology Group (CCBG), DETEMA, Facultad de Química, UdelaR, Montevideo, Uruguay.
| | - Mariano Teruel
- Laboratorio Universitario de Química y Contaminación Del Aire (L.U.Q.C.A.), Instituto de Investigaciones en Fisicoquímica de Córdoba (I.N.F.I.Q.C.), CONICET, Dpto. de Fisicoquímica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Ciudad Universitaria, 5000, Córdoba, Argentina.
| | - Oscar N Ventura
- Computational Chemistry and Biology Group (CCBG), DETEMA, Facultad de Química, UdelaR, Montevideo, Uruguay.
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3
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Caster KL, Lee J, Donnellan Z, Selby TM, Osborn DL, Goulay F. Formation of a Resonance-Stabilized Radical Intermediate by Hydroxyl Radical Addition to Cyclopentadiene. J Phys Chem A 2022; 126:9031-9041. [DOI: 10.1021/acs.jpca.2c06934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Affiliation(s)
- Kacee L. Caster
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia26506, United States
| | - James Lee
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia26506, United States
| | - Zachery Donnellan
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia26506, United States
| | - Talitha M. Selby
- Department of Mathematics and Natural Sciences, University of Wisconsin-Milwaukee, West Bend, Wisconsin53095, United States
| | - David L. Osborn
- Combustion Research Facility, Sandia National Laboratories, Mail Stop 9055, Livermore, California94551, United States
- Department of Chemical Engineering, University of California, Davis, Davis, California95616, United States
| | - Fabien Goulay
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia26506, United States
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4
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Cardona AL, Gibilisco RG, Rivela CB, Blanco MB, Patroescu-Klotz I, Illmann N, Wiesen P, Teruel MA. Kinetics, product distribution and atmospheric implications of the gas-phase oxidation of allyl sulfides by OH radicals. CHEMOSPHERE 2022; 288:132546. [PMID: 34653479 DOI: 10.1016/j.chemosphere.2021.132546] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 10/07/2021] [Accepted: 10/10/2021] [Indexed: 06/13/2023]
Abstract
Relative rate coefficients of the OH radical -initiated oxidation of allyl methyl sulfide (AMS, H2CCHCH2SCH3) and allyl ethyl sulfide (AES, H2CCHCH2SCH2CH3) have been measured at atmospheric pressure of synthetic air and 298 K: kAMS= (4.98 ± 1.42) and kAES= (6.88 ± 1.49) × 10-11 cm3 molecule-1 s-1 by means of in situ FTIR spectroscopy. In addition, the molar yields of the main reaction products of AMS with OH radicals formed in the absence and presence of nitric oxides (NOX) were determined to be the following: sulfur dioxide (95 ± 12) % and (51 ± 12) % for acrolein (50 ± 9) % and (41 ± 9) %. In the reaction of AES with OH radicals, the following molar yields were obtained: for sulfur dioxide (88 ± 13) % and (56 ± 12) % for acrolein (36 ± 9) % and (41 ± 9) %. The present results suggest that the abstraction at C3 plays an important role in the oxidation mechanism as the addition to the double bond. This work represents the first study of the OH radical interaction with AMS and AES carried out under atmospheric conditions. The atmospheric implications were discussed in terms of the atmospheric residence times of the sulfur-containing compounds studied and the products formed in the presence and absence of NOx. SO2 formation seems to be the main fate of the gas-phase allyl sulfides oxidation with significant acidifying potentials and short-chain aldehydes production like formaldehyde and acetaldehyde.
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Affiliation(s)
- Alejandro L Cardona
- (L.U.Q.C.A), Laboratorio Universitario de Química y Contaminación del Aire., Instituto de Investigaciones en Fisicoquímica de Córdoba (I.N.F.I.Q.C.), CONICET, Dpto., de Fisicoquímica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba., Ciudad Universitaria, 5000, Córdoba, Argentina
| | - Rodrigo G Gibilisco
- LEA - Laboratorio de Estudios Atmosféricos- INQUINOA (CONICET-UNT), Facultad de Bioquímica, Química y Farmacia, Universidad Nacional de Tucumán, San Lorenzo 456, T4000CAN, San Miguel de Tucumán, Argentina
| | - Cynthia B Rivela
- (L.U.Q.C.A), Laboratorio Universitario de Química y Contaminación del Aire., Instituto de Investigaciones en Fisicoquímica de Córdoba (I.N.F.I.Q.C.), CONICET, Dpto., de Fisicoquímica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba., Ciudad Universitaria, 5000, Córdoba, Argentina
| | - María B Blanco
- (L.U.Q.C.A), Laboratorio Universitario de Química y Contaminación del Aire., Instituto de Investigaciones en Fisicoquímica de Córdoba (I.N.F.I.Q.C.), CONICET, Dpto., de Fisicoquímica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba., Ciudad Universitaria, 5000, Córdoba, Argentina
| | - Iulia Patroescu-Klotz
- Institute for Atmospheric and Environmental Research, Faculty for Mathematics and Natural Sciences, University of Wuppertal, D-42097, Wuppertal, Germany
| | - Niklas Illmann
- Institute for Atmospheric and Environmental Research, Faculty for Mathematics and Natural Sciences, University of Wuppertal, D-42097, Wuppertal, Germany
| | - Peter Wiesen
- Institute for Atmospheric and Environmental Research, Faculty for Mathematics and Natural Sciences, University of Wuppertal, D-42097, Wuppertal, Germany
| | - Mariano A Teruel
- (L.U.Q.C.A), Laboratorio Universitario de Química y Contaminación del Aire., Instituto de Investigaciones en Fisicoquímica de Córdoba (I.N.F.I.Q.C.), CONICET, Dpto., de Fisicoquímica, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba., Ciudad Universitaria, 5000, Córdoba, Argentina.
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5
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Sha H, Nie J, Lian L, Yan S, Song W. Phototransformation of an emerging cyanotoxin (Aerucyclamide A) in simulated natural waters. WATER RESEARCH 2021; 201:117339. [PMID: 34157574 DOI: 10.1016/j.watres.2021.117339] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/11/2021] [Revised: 06/01/2021] [Accepted: 06/06/2021] [Indexed: 06/13/2023]
Abstract
Aerucyclamide A (ACA) is an emerging cyanopeptide toxin produced by cyanobacteria, and its transformation pathway has rarely been reported. In the present study, ACA was purified from cyanobacterial extracts, and photodegradation processes were investigated in dissolved organic matter (DOM) solutions. Under simulated solar irradiation, the photodegradation of ACA was dominated by •OH oxidation, accounting for ~72% of the indirect photodegradation. The bimolecular reaction rate constant of ACA with •OH was (6.4 ± 0.2) × 109M - 1s - 1. Our results indicated that the major reactive sites of ACA toward •OH are thiazoline and thiazole moieties. Product analysis via high-resolution mass spectrometry suggested that hydrogen abstraction and gradual hydroxylation are the main photodegradation pathways. The acute toxicity assessment indicate that the products generated in photolysis process did not show any measurable toxicity to Thamnocephalus platyurus. Photodegradation experiments with various DOM-phycocyanin mixtures demonstrated that the half-life of ACA is much longer than that of microcystin-LR.
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Affiliation(s)
- Haitao Sha
- Department of Environmental Science and Engineering, Fudan University, Shanghai, 200438, PR China
| | - Jianxin Nie
- Department of Environmental Science and Engineering, Fudan University, Shanghai, 200438, PR China
| | - Lushi Lian
- School of Ecological and Environmental Sciences, East China Normal University, Shanghai, 200241, PR China
| | - Shuwen Yan
- Department of Environmental Science and Engineering, Fudan University, Shanghai, 200438, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, PR China.
| | - Weihua Song
- Department of Environmental Science and Engineering, Fudan University, Shanghai, 200438, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai, 200092, PR China.
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6
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Sullivan EN, Saric S, Neumark DM. Photodissociation of iso-propoxy (i-C 3H 7O) radical at 248 nm. Phys Chem Chem Phys 2020; 22:17738-17748. [DOI: 10.1039/d0cp02493g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Photodissociation of the i-C3H7O radical is investigated using fast beam photofragment translational spectroscopy.
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Affiliation(s)
- Erin N. Sullivan
- Department of Chemistry
- University of California
- Berkeley
- USA
- Chemical Sciences Division
| | - Steven Saric
- Department of Chemistry
- University of California
- Berkeley
- USA
- Chemical Sciences Division
| | - Daniel M. Neumark
- Department of Chemistry
- University of California
- Berkeley
- USA
- Chemical Sciences Division
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7
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Wennberg PO, Bates KH, Crounse JD, Dodson LG, McVay RC, Mertens LA, Nguyen TB, Praske E, Schwantes RH, Smarte MD, St Clair JM, Teng AP, Zhang X, Seinfeld JH. Gas-Phase Reactions of Isoprene and Its Major Oxidation Products. Chem Rev 2018. [PMID: 29522327 DOI: 10.1021/acs.chemrev.7b00439] [Citation(s) in RCA: 145] [Impact Index Per Article: 24.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Isoprene carries approximately half of the flux of non-methane volatile organic carbon emitted to the atmosphere by the biosphere. Accurate representation of its oxidation rate and products is essential for quantifying its influence on the abundance of the hydroxyl radical (OH), nitrogen oxide free radicals (NO x), ozone (O3), and, via the formation of highly oxygenated compounds, aerosol. We present a review of recent laboratory and theoretical studies of the oxidation pathways of isoprene initiated by addition of OH, O3, the nitrate radical (NO3), and the chlorine atom. From this review, a recommendation for a nearly complete gas-phase oxidation mechanism of isoprene and its major products is developed. The mechanism is compiled with the aims of providing an accurate representation of the flow of carbon while allowing quantification of the impact of isoprene emissions on HO x and NO x free radical concentrations and of the yields of products known to be involved in condensed-phase processes. Finally, a simplified (reduced) mechanism is developed for use in chemical transport models that retains the essential chemistry required to accurately simulate isoprene oxidation under conditions where it occurs in the atmosphere-above forested regions remote from large NO x emissions.
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8
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Bourgalais J, Spencer M, Osborn DL, Goulay F, Le Picard SD. Reactions of Atomic Carbon with Butene Isomers: Implications for Molecular Growth in Carbon-Rich Environments. J Phys Chem A 2016; 120:9138-9150. [PMID: 27798961 DOI: 10.1021/acs.jpca.6b09785] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- J. Bourgalais
- Institut
de Physique de Rennes, Département de Physique Moléculaire, Astrophysique de Laboratoire, UMR CNRS 6251, Université de Rennes 1, Campus de Beaulieu, 35042 Rennes Cedex, France
| | - Michael Spencer
- Department
of Chemistry, West Virginia University, Morgantown, West Virginia 26506, United States
| | - David L. Osborn
- Combustion
Research Facility, Mail Stop 9055, Sandia National Laboratories, Livermore, California 94551, United States
| | - F. Goulay
- Department
of Chemistry, West Virginia University, Morgantown, West Virginia 26506, United States
| | - S. D. Le Picard
- Institut
de Physique de Rennes, Département de Physique Moléculaire, Astrophysique de Laboratoire, UMR CNRS 6251, Université de Rennes 1, Campus de Beaulieu, 35042 Rennes Cedex, France
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9
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Trevitt AJ, Goulay F. Insights into gas-phase reaction mechanisms of small carbon radicals using isomer-resolved product detection. Phys Chem Chem Phys 2016; 18:5867-82. [DOI: 10.1039/c5cp06389b] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Gas-phase radical reactions of CN and CH with small hydrocarbons are overviewed with emphasis on isomer-resolved product detection.
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Affiliation(s)
- Adam J. Trevitt
- School of Chemistry
- University of Wollongong
- Wollongong
- Australia
| | - Fabien Goulay
- Department of Chemistry
- West Virginia University
- Morgantown
- USA
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10
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Brynteson MD, Womack CC, Booth RS, Lee SH, Lin JJ, Butler LJ. Radical intermediates in the addition of OH to propene: photolytic precursors and angular momentum effects. J Phys Chem A 2014; 118:3211-29. [PMID: 24758210 DOI: 10.1021/jp4108987] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We investigate the photolytic production of two radical intermediates in the reaction of OH with propene, one from addition of the hydroxyl radical to the terminal carbon and the other from addition to the center carbon. In a collision-free environment, we photodissociate a mixture of 1-bromo-2-propanol and 2-bromo-1-propanol at 193 nm to produce these radical intermediates. The data show two primary photolytic processes occur: C-Br photofission and HBr photoelimination. Using a velocity map imaging apparatus, we measured the speed distribution of the recoiling bromine atoms, yielding the distribution of kinetic energies of the nascent C3H6OH radicals + Br. Resolving the velocity distributions of Br((2)P(1/2)) and Br((2)P(3/2)) separately with 2 + 1 REMPI allows us to determine the total (vibrational + rotational) internal energy distribution in the nascent radicals. Using an impulsive model to estimate the rotational energy imparted to the nascent C3H6OH radicals, we predict the percentage of radicals having vibrational energy above and below the lowest dissociation barrier, that to OH + propene; it accurately predicts the measured velocity distribution of the stable C3H6OH radicals. In addition, we use photofragment translational spectroscopy to detect several dissociation products of the unstable C3H6OH radicals: OH + propene, methyl + acetaldehyde, and ethyl + formaldehyde. We also use the angular momenta of the unstable radicals and the tensor of inertia of each to predict the recoil kinetic energy and angular distributions when they dissociate to OH + propene; the prediction gives an excellent fit to the data.
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Affiliation(s)
- M D Brynteson
- Department of Chemistry and the James Franck Institute, The University of Chicago , Chicago, Illinois 60637, United States
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11
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Zhang P, Klippenstein SJ, Law CK. Ab initio kinetics for the decomposition of hydroxybutyl and butoxy radicals of n-butanol. J Phys Chem A 2013; 117:1890-906. [PMID: 23394217 DOI: 10.1021/jp400155z] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The decomposition kinetics of the hydroxybutyl and butoxy radicals (C4H9O) arising via H abstraction from n-butanol were studied theoretically with ab initio transition-state-theory-based master equation analyses. Stationary points on the C4H9O potential energy surface were calculated at either the RQCISD(T)/CBS//B3LYP/6-311++G(d,p) level or the RQCISD(T)/CBS//CASPT2/aug-cc-pVDZ level. Unimolecular pressure- and temperature-dependent rate coefficients were calculated over broad ranges of temperature (300-2500 K) and pressure (1.3 × 10(-3) to 10(2) atm) by solving the time-dependent multiple-well master equation. The "well merging" phenomenon was observed and analyzed for its influence on the branching ratios and rate coefficients. The theoretical predictions were compared with the available experimental and theoretical data and any discrepancies were analyzed. The predicted rate coefficients are represented with forms that may readily be used in combustion modeling of n-butanol.
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Affiliation(s)
- Peng Zhang
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544, United States
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12
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Loison JC, Rayez MT, Rayez JC, Gratien A, Morajkar P, Fittschen C, Villenave E. Gas-Phase Reaction of Hydroxyl Radical with Hexamethylbenzene. J Phys Chem A 2012. [DOI: 10.1021/jp307568c] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Jean-Christophe Loison
- Universite Bordeaux, ISM, UMR 5255, F-33400
Talence, France
- CNRS, ISM, UMR 5255, F-33400 Talence, France
| | - Marie-Thérèse Rayez
- Universite Bordeaux, ISM, UMR 5255, F-33400
Talence, France
- CNRS, ISM, UMR 5255, F-33400 Talence, France
| | - Jean-Claude Rayez
- Universite Bordeaux, ISM, UMR 5255, F-33400
Talence, France
- CNRS, ISM, UMR 5255, F-33400 Talence, France
| | - Aline Gratien
- Universite Bordeaux, ISM, UMR 5255, F-33400
Talence, France
- CNRS, ISM, UMR 5255, F-33400 Talence, France
| | - Pranay Morajkar
- Universite Bordeaux, ISM, UMR 5255, F-33400
Talence, France
- CNRS, ISM, UMR 5255, F-33400 Talence, France
- Universite Lille, PC2A, UMR 8522, F-59655 Villeneuve d’Ascq, France
- CNRS,
PC2A, UMR 8522, F-59655 Villeneuve d’Ascq, France
| | - Christa Fittschen
- Universite Lille, PC2A, UMR 8522, F-59655 Villeneuve d’Ascq, France
- CNRS,
PC2A, UMR 8522, F-59655 Villeneuve d’Ascq, France
| | - Eric Villenave
- Universite Bordeaux, ISM, UMR 5255, F-33400
Talence, France
- CNRS, ISM, UMR 5255, F-33400 Talence, France
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13
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Daranlot J, Hickson KM, Loison JC, Méreau R, Caralp F, Forst W, Bergeat A. Gas-phase kinetics of the hydroxyl radical reaction with allene: absolute rate measurements at low temperature, product determinations, and calculations. J Phys Chem A 2012; 116:10871-81. [PMID: 23126232 DOI: 10.1021/jp304831x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The gas phase reaction of the hydroxyl radical with allene has been studied theoretically and experimentally in a continuous supersonic flow reactor over the range 50 ≤ T/K ≤ 224. This reaction has been found to exhibit a negative temperature dependence over the entire temperature range investigated, varying between (0.75 and 5.0) × 10(-11) cm(3) molecule(-1) s(-1). Product formation from the reaction of OH and OD radicals with allene (C(3)H(4)) has been investigated in a fast flow reactor through time-of-flight mass spectrometry, at pressures between 0.8 and 2.4 Torr. The branching ratios for adduct formation (C(3)H(4)OH) in this pressure range are found to be equal to 34 ± 16% and 48 ± 16% for the OH and OD + allene reactions, respectively, the only other channel being the formation of CH(3) or CH(2)D + H(2)CCO (ketene). Moreover, the rate constant for the OD + C(3)H(4) reaction is also found to be 1.4 times faster than the rate constant for the OH + C(3)H(4) reaction at 1.5 Torr and at 298 K. The experimental results and implications for atmospheric chemistry have been rationalized by quantum chemical and RRKM calculations.
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14
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Kline ND, Miller TA. Analysis of the A∼–X∼ electronic transition of the 2,1-hydroxypropylperoxy radical using cavity ringdown spectroscopy. Chem Phys Lett 2012. [DOI: 10.1016/j.cplett.2012.01.056] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/14/2022]
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15
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Ziemann PJ, Atkinson R. Kinetics, products, and mechanisms of secondary organic aerosol formation. Chem Soc Rev 2012; 41:6582-605. [DOI: 10.1039/c2cs35122f] [Citation(s) in RCA: 423] [Impact Index Per Article: 35.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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16
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Vereecken L, Francisco JS. Theoretical studies of atmospheric reaction mechanisms in the troposphere. Chem Soc Rev 2012; 41:6259-93. [DOI: 10.1039/c2cs35070j] [Citation(s) in RCA: 311] [Impact Index Per Article: 25.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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17
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Competing Channels in the Propene + OH Reaction: Experiment and Validated Modeling over a Broad Temperature and Pressure Range. ACTA ACUST UNITED AC 2011. [DOI: 10.1524/zpch.2011.0165] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Abstract
Although the propene + OH reaction has been in the center of interest of numerous experimental and theoretical studies, rate coefficients have never been determined experimentally between ∼600 and ∼750 K, where the reaction is governed by the complex interaction of addition, back-dissociation and abstraction. In this work OH time-profiles are measured in two independent laboratories over a wide temperature region (200–950 K) and are analyzed incorporating recent theoretical results. The datasets are consistent both with each other and with the calculated rate coefficients. We present a simplified set of reactions validated over a broad temperature and pressure range, that can be used in smaller combustion models for propene + OH. In addition, the experimentally observed kinetic isotope effect for the abstraction is rationalized using ab initio calculations and variational transition-state theory. We recommend the following approximate description of the OH + C3H6 reaction
C3H6 + OH ⇆ C3H6OH (R1a,R-1a)
C3H6 + OH → C3H5 + H2O (R1b)
k
1a
(200 K ≤ T ≤ 950 K; 1 bar ≤ P) = 1.45 × 10-11 (T/K)-0.18
e
460 K/T
cm3 molecule-1 s-1
k
-1a
(200 K ≤ T ≤ 950 K; 1 bar ≤ P) = 5.74 × 1012
e
-12690 K/T
s-1
k
1b
(200 K ≤ T ≤ 950 K) = 1.63 × 10-18 (T/K)2.36
e
-725 K/T
cm3 molecule-1 s-1
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