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Hass SA, Andersen ST, Nielsen OJ. Trichloroacetyl chloride, CCl 3COCl, as an alternative Cl atom precursor for laboratory use and determination of Cl atom rate coefficients for n-CH 2[double bond, length as m-dash]CH(CH 2) xCN (x = 3-4). ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2020; 22:1347-1354. [PMID: 32356541 DOI: 10.1039/d0em00105h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
An investigation of CCl3COCl was conducted with the purpose of using the compound as an alternative Cl atom precursor in laboratory settings. CCl3COCl can be used with or without O2 as a source of Cl atoms and photolysis studies in air and N2 diluent displayed COCl2 and CO as being the major photolysis products. Relative rate studies were performed to determine the Cl atom rate coefficients for reaction with CH3Cl and C2H2 and the results were in agreement with literature values. Cl atom rate coefficients for reaction with n-CH2[double bond, length as m-dash]CH(CH2)3CN and n-CH2[double bond, length as m-dash]CH(CH2)4CN were determined as (2.95 ± 0.58) × 10-10 and (3.73 ± 0.60) × 10-10 cm3 molecule-1 s-1, respectively. CCl3COCl requires UV-C irradiation, so not all molecules are feasible for use in e.g. relative rate studies. Furthermore, it is recommended to perform experiments with O2 present, as this minimizes IR feature disturbance from product formation.
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Affiliation(s)
- Sofie Askjær Hass
- Copenhagen Center for Atmospheric Research, Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen Ø, Denmark.
| | - Simone Thirstrup Andersen
- Copenhagen Center for Atmospheric Research, Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen Ø, Denmark.
| | - Ole John Nielsen
- Copenhagen Center for Atmospheric Research, Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen Ø, Denmark.
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Song X, Zügner GL, Farkas M, Illés Á, Sarzyński D, Rozgonyi T, Wang B, Dóbé S. Experimental and Theoretical Study on the OH-Reaction Kinetics and Photochemistry of Acetyl Fluoride (CH3C(O)F), an Atmospheric Degradation Intermediate of HFC-161 (C2H5F). J Phys Chem A 2015; 119:7753-65. [PMID: 25859909 DOI: 10.1021/acs.jpca.5b01069] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The direct reaction kinetic method of low pressure fast discharge flow (DF) with resonance fluorescence monitoring of OH (RF) has been applied to determine rate coefficients for the overall reactions OH + C2H5F (EtF) (1) and OH + CH3C(O)F (AcF) (2). Acetyl fluoride reacts slowly with the hydroxyl radical, the rate coefficient at laboratory temperature is k2(300 K) = (0.74 ± 0.05) × 10(-14) cm(3) molecule(-1) s(-1) (given with 2σ statistical uncertainty). The temperature dependence of the reaction does not obey the Arrhenius law and it is described well by the two-exponential rate expression of k2(300-410 K) = 3.60 × 10(-3) exp(-10500/T) + 1.56 × 10(-13) exp(-910/T) cm(3) molecule(-1) s(-1). The rate coefficient of k1 = (1.90 ± 0.19) × 10(-13) cm(3) molecule(-1) s(-1) has been determined for the EtF-reaction at room temperature (T = 298 K). Microscopic mechanisms for the OH + CH3C(O)F reaction have also been studied theoretically using the ab initio CBS-QB3 and G4 methods. Variational transition state theory was employed to obtain rate coefficients for the OH + CH3C(O)F reaction as a function of temperature on the basis of the ab initio data. The calculated rate coefficients are in good agreement with the experimental data. It is revealed that the reaction takes place predominantly via the indirect H-abstraction mechanism involving H-bonded prereactive complexes and forming the nascent products of H2O and the CH2CFO radical. The non-Arrhenius behavior of the rate coefficient at temperatures below 500 K is ascribed to the significant tunneling effect of the in-the-plane H-abstraction dynamic bottleneck. The production of FC(O)OH + CH3 via the addition/elimination mechanism is hardly competitive due to the significant barriers along the reaction routes. Photochemical experiments of AcF were performed at 248 nm by using exciplex lasers. The total photodissociation quantum yield for CH3C(O)F has been found significantly less than unity; among the primary photochemical processes, C-C bond cleavage is by far dominating compared with CO-elimination. The absorption spectrum of AcF has also been determined by displaying a strong blue shift compared with the spectra of aliphatic carbonyls. Consequences of the results on atmospheric chemistry have been discussed.
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Affiliation(s)
- Xinli Song
- †College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, People's Republic of China
| | - Gábor L Zügner
- ‡Institute of Materials and Environmental Chemistry, Research Centre for Natural Sciences, Hungarian Academy of Sciences, 1117 Budapest, Hungary
| | - Mária Farkas
- ‡Institute of Materials and Environmental Chemistry, Research Centre for Natural Sciences, Hungarian Academy of Sciences, 1117 Budapest, Hungary
| | - Ádám Illés
- ‡Institute of Materials and Environmental Chemistry, Research Centre for Natural Sciences, Hungarian Academy of Sciences, 1117 Budapest, Hungary
| | - Dariusz Sarzyński
- §Department of Physical Chemistry, Wroclaw Medical University, 50-556 Wroclaw, Poland
| | - Tamás Rozgonyi
- ‡Institute of Materials and Environmental Chemistry, Research Centre for Natural Sciences, Hungarian Academy of Sciences, 1117 Budapest, Hungary
| | - Baoshan Wang
- †College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, People's Republic of China
| | - Sándor Dóbé
- ‡Institute of Materials and Environmental Chemistry, Research Centre for Natural Sciences, Hungarian Academy of Sciences, 1117 Budapest, Hungary
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Wang H, Wang B, Wang B, Yang B. Theoretical study of a reaction mechanism of tropospheric interest: CH 3CH 2F + OH. PROGRESS IN REACTION KINETICS AND MECHANISM 2013. [DOI: 10.3184/146867813x13744829848125] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Dual-level electronic structure calculation has been performed to investigate the mechanism and all possible channels of OH radical reaction with CH3CH2F. Geometries and frequencies are computed at the B3LYP/6-311G(d,p) level of theory for all stationary points and complexes and transition states are located. Potential energy surfaces are constructed at the PMP2/cc-pVTZ//B3LYP/6-311G(d,p) level + ZPE correction. Four types of reaction channels are identified: hydrogen abstraction, fluorine abstraction and attack on carbon atom along or perpendicular to the C–C bond axis. Hydrogen abstraction channels have lower barriers and are more exothermic, while out-of-plane β–H abstraction with the lowest barrier is competitive with a–H abstraction. Due to the high energy barrier, contributions of non-H abstraction channels are excluded. The influence of hydrogen bonding interaction is clearly observed in the barrier heights.
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Affiliation(s)
- Hongliang Wang
- College of Resources and Environment, Henan Institute of Science and Technology, Xinxiang 453003, P.R. China
| | - Bingxing Wang
- College of Chemistry and Chemical Engineering, Harbin Normal University, Harbin 150025, P.R. China
| | - Bingli Wang
- College of Resources and Environment, Henan Institute of Science and Technology, Xinxiang 453003, P.R. China
| | - Bing Yang
- State Key Laboratory of Supramolecular Structure and Materials, Jilin University, Changchun 130012, P.R. China
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Lucena JR, Sharma A, Reva ID, Araújo RMCU, Ventura E, do Monte SA, Braga CF, Ramos MN, Fausto R. Matrix Isolation FTIR Spectroscopic and Theoretical Study of 3,3-Dichloro-1,1,1-Trifluoropropane (HCFC-243). J Phys Chem A 2008; 112:11641-8. [DOI: 10.1021/jp807388a] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- J. R. Lucena
- Departamento de Química, Universidade Federal da Paraíba, 58059-900 João Pessoa-PB, Brazil, Departamento de Química, Universidade of Coimbra, 3004-535 Coimbra, Portugal, and Departamento de Química Fundamental, Universidade Federal de Pernambuco, 50739−901-Recife-PE, Brazil
| | - A. Sharma
- Departamento de Química, Universidade Federal da Paraíba, 58059-900 João Pessoa-PB, Brazil, Departamento de Química, Universidade of Coimbra, 3004-535 Coimbra, Portugal, and Departamento de Química Fundamental, Universidade Federal de Pernambuco, 50739−901-Recife-PE, Brazil
| | - I. D. Reva
- Departamento de Química, Universidade Federal da Paraíba, 58059-900 João Pessoa-PB, Brazil, Departamento de Química, Universidade of Coimbra, 3004-535 Coimbra, Portugal, and Departamento de Química Fundamental, Universidade Federal de Pernambuco, 50739−901-Recife-PE, Brazil
| | - R. M. C. U. Araújo
- Departamento de Química, Universidade Federal da Paraíba, 58059-900 João Pessoa-PB, Brazil, Departamento de Química, Universidade of Coimbra, 3004-535 Coimbra, Portugal, and Departamento de Química Fundamental, Universidade Federal de Pernambuco, 50739−901-Recife-PE, Brazil
| | - E. Ventura
- Departamento de Química, Universidade Federal da Paraíba, 58059-900 João Pessoa-PB, Brazil, Departamento de Química, Universidade of Coimbra, 3004-535 Coimbra, Portugal, and Departamento de Química Fundamental, Universidade Federal de Pernambuco, 50739−901-Recife-PE, Brazil
| | - S. A. do Monte
- Departamento de Química, Universidade Federal da Paraíba, 58059-900 João Pessoa-PB, Brazil, Departamento de Química, Universidade of Coimbra, 3004-535 Coimbra, Portugal, and Departamento de Química Fundamental, Universidade Federal de Pernambuco, 50739−901-Recife-PE, Brazil
| | - C. F. Braga
- Departamento de Química, Universidade Federal da Paraíba, 58059-900 João Pessoa-PB, Brazil, Departamento de Química, Universidade of Coimbra, 3004-535 Coimbra, Portugal, and Departamento de Química Fundamental, Universidade Federal de Pernambuco, 50739−901-Recife-PE, Brazil
| | - M. N. Ramos
- Departamento de Química, Universidade Federal da Paraíba, 58059-900 João Pessoa-PB, Brazil, Departamento de Química, Universidade of Coimbra, 3004-535 Coimbra, Portugal, and Departamento de Química Fundamental, Universidade Federal de Pernambuco, 50739−901-Recife-PE, Brazil
| | - R. Fausto
- Departamento de Química, Universidade Federal da Paraíba, 58059-900 João Pessoa-PB, Brazil, Departamento de Química, Universidade of Coimbra, 3004-535 Coimbra, Portugal, and Departamento de Química Fundamental, Universidade Federal de Pernambuco, 50739−901-Recife-PE, Brazil
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Sun H, He H, Liu J, Li Z, Pan X, Wang R. Direct Ab initio dynamics study on the reaction of CH3CHF2 (HFC-152a) with the Cl atom. Chemphyschem 2008; 9:847-53. [PMID: 18357589 DOI: 10.1002/cphc.200700590] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
A direct ab initio dynamics method is used to investigate the hydrogen-abstraction reaction CH(3)CHF(2)+Cl. One transition state is located for alpha-H abstraction, and two are identified for beta-H abstraction. The potential-energy surface (PES) is obtained at the G3(MP2)//MP2/6-311G(d, p) level. Furthermore, the rate constants of the three channels are evaluated by using canonical variational transition-state theory (CVT) with small-curvature tunneling (SCT) contributions over a wide temperature range of 200-2500 K. The dynamic calculations show that the reaction proceeds mainly by alpha-H abstraction over the whole temperature range. The calculated rate constants and branching ratios are both in good agreement with the available experimental values.
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Affiliation(s)
- Hao Sun
- Institute of Functional Material Chemistry, Faculty of Chemistry, Northeast Normal University, Renmin Street 5268, Changchun, Jilin 130024, P. R. China
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