1
|
Gui X, Fan W, Sun J, Li Y. New Stable and Fast Ring-Polymer Molecular Dynamics for Calculating Bimolecular Rate Coefficients with an Example of OH + CH 4. J Chem Theory Comput 2022; 18:5203-5212. [PMID: 35983956 DOI: 10.1021/acs.jctc.2c00522] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The accurate and efficient calculation of the rate coefficients of chemical reactions is a key issue in the research of chemical dynamics. In this work, by applying the dimension-free ultrastable Cayley propagator, the thermal rate coefficients of a prototypic high dimensional chemical reaction OH + CH4 → H2O + CH3 in the temperature range of 200 to 1500 K are investigated with ring polymer molecular dynamics (RPMD) on a highly accurate full-dimensional potential energy surface. Kinetic isotope effects (KIEs) for three isotopologues of the title reaction are also studied. The results demonstrate excellent agreement with experimental data, even in the deep tunneling region. Especially, the Cayley propagator shows a high calculation efficiency with little loss of accuracy. The present results confirmed the applicability of the RPMD method, particularly the speed-up using a Cayley propagator, in theoretical calculations of bimolecular reaction rates.
Collapse
Affiliation(s)
- Xiongfei Gui
- Department of Physics, International Center of Quantum and Molecular Structures, and Shanghai Frontiers Science Center of Quantum and Superconducting Matter States, Shanghai 200444, China
| | - Wenbin Fan
- Department of Chemistry, Fudan University, Shanghai 200433, China
| | - Jiace Sun
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California 91125, United States
| | - Yongle Li
- Department of Physics, International Center of Quantum and Molecular Structures, and Shanghai Frontiers Science Center of Quantum and Superconducting Matter States, Shanghai 200444, China
| |
Collapse
|
2
|
|
3
|
Dual Fuel Reaction Mechanism 2.0 including NOx Formation and Laminar Flame Speed Calculations Using Methane/Propane/n-Heptane Fuel Blends. ENERGIES 2020. [DOI: 10.3390/en13040778] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
This study presents the further development of the TU Wien dual fuel mechanism, which was optimized for simulating ignition and combustion in a rapid compression expansion machine (RCEM) in dual fuel mode using diesel and natural gas at pressures higher than 60 bar at the start of injection. The mechanism is based on the Complete San Diego mechanism with n-heptane extension and was attuned to the RCEM measurements to achieve high agreement between experiments and simulation. This resulted in a specific application area. To obtain a mechanism for a wider parameter range, the Arrhenius parameter changes performed were analyzed and updated. Furthermore, the San Diego nitrogen sub-mechanism was added to consider NOx formation. The ignition delay time-reducing effect of propane addition to methane was closely examined and improved. To investigate the propagation of the flame front, the laminar flame speed of methane–air mixtures was simulated and compared with measured values from literature. Deviations at stoichiometric and fuel-rich conditions were found and by further mechanism optimization reduced significantly. To be able to justify the parameter changes performed, the resulting reaction rate coefficients were compared with data from the National Institute of Standards and Technology chemical kinetics database.
Collapse
|
4
|
A Novel Dual Fuel Reaction Mechanism for Ignition in Natural Gas–Diesel Combustion. ENERGIES 2019. [DOI: 10.3390/en12224396] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
In this study, a reaction mechanism is presented that is optimized for the simulation of the dual fuel combustion process using n-heptane and a mixture of methane/propane as surrogate fuels for diesel and natural gas, respectively. By comparing the measured and calculated ignition delay times (IDTs) of different homogeneous methane–propane–n-heptane mixtures, six different n-heptane mechanisms were investigated and evaluated. The selected mechanism was used for computational fluid dynamics (CFD) simulations to calculate the ignition of a diesel spray injected into air and a natural gas–air mixture. The observed deviations between the simulation results and the measurements performed with a rapid compression expansion machine (RCEM) and a combustion vessel motivated the adaptation of the mechanism by adjusting the Arrhenius parameters of individual reactions. For the identification of the reactions suitable for the mechanism adaption, sensitivity and flow analyzes were performed. The adjusted mechanism is able to describe ignition phenomena in the context of natural gas–diesel, i.e., dual fuel combustion.
Collapse
|
5
|
Li J, Guo H. Thermal Rate Coefficients and Kinetic Isotope Effects for the Reaction OH + CH4 → H2O + CH3 on an ab Initio-Based Potential Energy Surface. J Phys Chem A 2018; 122:2645-2652. [DOI: 10.1021/acs.jpca.8b01201] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Jun Li
- School of Chemistry and Chemical Engineering, Chongqing University, Chongqing 401331, China
| | - Hua Guo
- Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, New Mexico 87131, United States
| |
Collapse
|
6
|
Bedjanian Y. Kinetics and Products of the Reaction of OH Radicals with ClNO from 220 to 940 K. J Phys Chem A 2018; 122:916-922. [PMID: 29304283 DOI: 10.1021/acs.jpca.7b11946] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The kinetics and products of the reaction of OH radicals with ClNO have been studied in a flow reactor coupled with an electron impact ionization mass spectrometer at nearly 2 Torr total pressure of helium and over a wide temperature range, T = 220-940 K. The rate constant of the reaction OH + ClNO → products was determined under pseudo-first order conditions, monitoring the kinetics of OH consumption in excess of ClNO: k1 = 1.48 × 10-18 × T2.12 exp(146/T) cm3 molecule-1 s-1 (uncertainty of 15%). HOCl, Cl, and HONO were observed as the reaction products. As a result of quantitative detection of HOCl and Cl, the partial rate constants of the HOCl + NO and Cl + HONO forming reaction pathways were determined in the temperature range 220-940 K: k1a = 3.64 × 10-18 × T1.99 exp(-114/T) and k1b = 4.71 × 10-18 × T1.74 exp(246/T) cm3 molecule-1 s-1 (uncertainty of 20%). The dynamics of the title reaction and, in particular, non-Arrhenius behavior observed for both k1a and k1b in a wide temperature range, seems to be an interesting topic for theoretical research.
Collapse
Affiliation(s)
- Yuri Bedjanian
- Institut de Combustion, Aérothermique, Réactivité et Environnement (ICARE), CNRS 45071 Orléans Cedex 2, France
| |
Collapse
|
7
|
|
8
|
Stone D, Blitz M, Ingham T, Onel L, Medeiros DJ, Seakins PW. An instrument to measure fast gas phase radical kinetics at high temperatures and pressures. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2016; 87:054102. [PMID: 27250442 DOI: 10.1063/1.4950906] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
Fast radical reactions are central to the chemistry of planetary atmospheres and combustion systems. Laser-induced fluorescence is a highly sensitive and selective technique that can be used to monitor a number of radical species in kinetics experiments, but is typically limited to low pressure systems owing to quenching of fluorescent states at higher pressures. The design and characterisation of an instrument are reported using laser-induced fluorescence detection to monitor fast radical kinetics (up to 25 000 s(-1)) at high temperatures and pressures by sampling from a high pressure reaction region to a low pressure detection region. Kinetics have been characterised at temperatures reaching 740 K and pressures up to 2 atm, with expected maximum operational conditions of up to ∼900 K and ∼5 atm. The distance between the point of sampling from the high pressure region and the point of probing within the low pressure region is critical to the measurement of fast kinetics. The instrumentation described in this work can be applied to the measurement of kinetics relevant to atmospheric and combustion chemistry.
Collapse
Affiliation(s)
- Daniel Stone
- School of Chemistry, University of Leeds, Leeds, United Kingdom
| | - Mark Blitz
- School of Chemistry, University of Leeds, Leeds, United Kingdom
| | - Trevor Ingham
- School of Chemistry, University of Leeds, Leeds, United Kingdom
| | - Lavinia Onel
- School of Chemistry, University of Leeds, Leeds, United Kingdom
| | | | - Paul W Seakins
- School of Chemistry, University of Leeds, Leeds, United Kingdom
| |
Collapse
|
9
|
Morin J, Romanias MN, Bedjanian Y. Experimental Study of the Reactions of OH Radicals with Propane, n
-Pentane, and n
-Heptane over a Wide Temperature Range. INT J CHEM KINET 2015. [DOI: 10.1002/kin.20936] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Affiliation(s)
- Julien Morin
- Institut de Combustion; Aérothermique; Réactivité et Environnement (ICARE); CNRS and Université d'Orléans; 45071 Orléans Cedex 2 France
| | - Manolis N. Romanias
- Institut de Combustion; Aérothermique; Réactivité et Environnement (ICARE); CNRS and Université d'Orléans; 45071 Orléans Cedex 2 France
| | - Yuri Bedjanian
- Institut de Combustion; Aérothermique; Réactivité et Environnement (ICARE); CNRS and Université d'Orléans; 45071 Orléans Cedex 2 France
| |
Collapse
|
10
|
Wang H, Qiu Y, Czakó G, Schaefer HF. Pathways for the OH + Cl2 → HOCl + Cl and HOCl + Cl → HCl + ClO Reactions. J Phys Chem A 2015; 119:7802-9. [PMID: 25965106 DOI: 10.1021/acs.jpca.5b01273] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
High level coupled-cluster theory, with spin-orbit coupling evaluated via the Breit-Pauli operator in the interacting-states approach, is used to investigate the OH radical reaction with Cl2 and the subsequent reaction HOCl + Cl. The entrance complex, transition state, and exit complex for both reactions have been determined using the CCSD(T) method with correlation consistent basis sets up to cc-pV6Z. Also reported are CCSDT computations. The OH + Cl2 reaction is predicted to be endothermic by 2.2 kcal/mol, compared to the best experiments, 2.0 kcal/mol. The above theoretical results include zero-point vibrational energy corrections and spin-orbit contributions. The activation energy (Ea) of the OH + Cl2 reaction predicted here, 2.3 kcal/mol, could be as much as 1 kcal/mol too high, but it falls among the four experimental Ea values, which span the range 1.1-2.5 kcal/mol. The exothermicity of the second reaction HOCl + Cl → HCl + ClO is 8.4 kcal/mol, compared to experiment 8.7 kcal/mol. The activation energy for latter reaction is unknown experimentally, but predicted here to be large, 11.5 kcal/mol. There are currently no experiments relevant to the theoretical entrance and exit complexes predicted here.
Collapse
Affiliation(s)
- Hongyan Wang
- †School of Physical Science and Technology, Southwest Jiaotong University, Key Laboratory of Advanced Technologies of Materials, Ministry of Education of China, Chengdu 610031, China.,‡Department of Chemistry and Center for Computational Quantum Chemistry, University of Georgia, Athens, Georgia 30602, United States
| | - Yudong Qiu
- ‡Department of Chemistry and Center for Computational Quantum Chemistry, University of Georgia, Athens, Georgia 30602, United States
| | - Gábor Czakó
- §Laboratory of Molecular Structure and Dynamics, Institute of Chemistry, Eötvös University, P.O. Box 32, H-1518 Budapest 112, Hungary
| | - Henry F Schaefer
- ‡Department of Chemistry and Center for Computational Quantum Chemistry, University of Georgia, Athens, Georgia 30602, United States
| |
Collapse
|
11
|
Paraskevas PD, Sabbe MK, Reyniers MF, Papayannakos NG, Marin GB. Group Additive Kinetics for Hydrogen Transfer Between Oxygenates. J Phys Chem A 2015; 119:6961-80. [DOI: 10.1021/acs.jpca.5b01668] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Paschalis D. Paraskevas
- Laboratorium
voor Chemische Technologie, Universiteit Gent, Technologiepark 914 9052, Zwijnaarde, Belgium
- National Technical University of Athens 9, Heroon Politechniou Str., 15780 Athens, Greece
| | - Maarten K. Sabbe
- Laboratorium
voor Chemische Technologie, Universiteit Gent, Technologiepark 914 9052, Zwijnaarde, Belgium
| | - Marie-Françoise Reyniers
- Laboratorium
voor Chemische Technologie, Universiteit Gent, Technologiepark 914 9052, Zwijnaarde, Belgium
| | - Nikos G. Papayannakos
- National Technical University of Athens 9, Heroon Politechniou Str., 15780 Athens, Greece
| | - Guy B. Marin
- Laboratorium
voor Chemische Technologie, Universiteit Gent, Technologiepark 914 9052, Zwijnaarde, Belgium
| |
Collapse
|
12
|
Suleimanov YV, Espinosa-Garcia J. Recrossing and Tunneling in the Kinetics Study of the OH + CH4 → H2O + CH3 Reaction. J Phys Chem B 2015; 120:1418-28. [DOI: 10.1021/acs.jpcb.5b02103] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Yury V. Suleimanov
- Department
of Chemical Engineering, Massachusetts Institute of Technology, 77 Massachusetts
Avenue, Cambridge, Massachusetts 02139, United States
- Computation-based Science and Technology
Research Center, Cyprus Institute, 20 Kavafi Street, Nicosia 2121, Cyprus
| | - J. Espinosa-Garcia
- Departamento de Química
Física, Universidad de Extremadura, 06071 Badajoz, Spain
| |
Collapse
|
13
|
Matsugi A, Shiina H. Kinetics of Hydrogen Abstraction Reactions from Fluoromethanes and Fluoroethanes. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2014. [DOI: 10.1246/bcsj.20140101] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Affiliation(s)
- Akira Matsugi
- Research Institute of Science for Safety and Sustainability, National Institute of Advanced Industrial Science and Technology
| | - Hiroumi Shiina
- Research Institute of Science for Safety and Sustainability, National Institute of Advanced Industrial Science and Technology
| |
Collapse
|
14
|
Badra J, Nasir EF, Farooq A. Site-specific rate constant measurements for primary and secondary H- and D-abstraction by OH radicals: propane and n-butane. J Phys Chem A 2014; 118:4652-60. [PMID: 24911449 DOI: 10.1021/jp503849b] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Site-specific rate constants for hydrogen (H) and deuterium (D) abstraction by hydroxyl (OH) radicals were determined experimentally by monitoring the reaction of OH with two normal and six deuterated alkanes. The studied alkanes include propane (C3H8), propane 2,2 D2 (CH3CD2CH3), propane 1,1,1-3,3,3 D6 (CD3CH2CD3), propane D8 (C3D8), n-butane (n-C4H10), butane 2,2-3,3 D4 (CH3CD2CD2CH3), butane 1,1,1-4,4,4 D6 (CD3CH2CH2CD3), and butane D10 (C4D10). Rate constant measurements were carried out over 840-1470 K and 1.2-2.1 atm using a shock tube and OH laser absorption. Previous low-temperature data were combined with the current high-temperature measurements to generate three-parameter fits which were then used to determine the site-specific rate constants. Two primary (P1,H and P1,D) and four secondary (S00,H, S00,D, S01,H, and S01,D) H- and D-abstraction rate constants, in which the subscripts refer to the number of C atoms connected to the next-nearest-neighbor C atom, are obtained. The modified Arrhenius expressions for the six site-specific abstractions by OH radicals are P1,H = 1.90 × 10(-18)T(2.00) exp(-340.87 K/T) cm(3) molecule(-1) s(-1) (210-1294 K); P1,D = 2.72 × 10(-17) T(1.60) exp(-895.57 K/T) cm(3) molecule(-1) s(-1) (295-1317 K); S00,H = 4.40 × 10(-18) T(1.93) exp(121.50 K/T) cm(3) molecule(-1) s(-1) (210-1294 K); S00,D = 1.45 × 10(-20) T(2.69) exp(282.36 K/T) cm(3) molecule(-1) s(-1) (295-1341 K); S01,H = 4.65 × 10(-17) T(1.60) exp(-236.98 K/T) cm(3) molecule(-1) s(-1) (235-1407 K); S01,D = 1.26 × 10(-18) T(2.07) exp(-77.00 K/T) cm(3) molecule(-1) s(-1) (294-1412 K).
Collapse
Affiliation(s)
- Jihad Badra
- Clean Combustion Research Center, Division of Physical Sciences and Engineering, King Abdullah University of Science and Technology (KAUST) , Thuwal 23955, Saudi Arabia
| | | | | |
Collapse
|
15
|
Park JH, Ivanov AV, Molina MJ. Experimental study on the release of Cl2 from NaCl upon OH radical uptake. Microchem J 2013. [DOI: 10.1016/j.microc.2013.08.011] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
16
|
Allen JW, Green WH, Li Y, Guo H, Suleimanov YV. Communication: Full dimensional quantum rate coefficients and kinetic isotope effects from ring polymer molecular dynamics for a seven-atom reaction OH + CH4 → CH3 + H2O. J Chem Phys 2013; 138:221103. [DOI: 10.1063/1.4811329] [Citation(s) in RCA: 64] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
|
17
|
Wang W, Zhao Y. Quantum instanton calculation of rate constant for CH4 + OH → CH3 + H2O reaction: torsional anharmonicity and kinetic isotope effect. J Chem Phys 2013; 137:214306. [PMID: 23231230 DOI: 10.1063/1.4768874] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Thermal rate constants for the title reaction are calculated by using the quantum instanton approximation within the full dimensional Cartesian coordinates. The results reveal that the quantum effect is remarkable for the reaction at both low and high temperatures, and the obtained rates are in good agreement with experimental measurements at high temperatures. Compared to the harmonic approximation, the torsional anharmonic effect of the internal rotation has a little influence on the rates at low temperatures, however, it enhances the rate by about 20% at 1000 K. In addition, the free energy barriers for the isotopic reactions and the temperature dependence of kinetic isotope effects are also investigated. Generally speaking, for the title reaction, the replacement of OH with OD will reduce the free energy barrier, while substituting D for H (connected to C) will increase the free energy barrier.
Collapse
Affiliation(s)
- Wenji Wang
- College of Science, Northwest A&F University, Shaanxi Province, Yangling, 712100, People's Republic of China.
| | | |
Collapse
|
18
|
Wang L, Zhao Y, Wen J, Zhang J. Mechanisms and kinetics of hydrogen abstraction of methylhydrazine and deuterated methylhydrazine with H/D atoms. Theor Chem Acc 2012. [DOI: 10.1007/s00214-012-1321-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
|
19
|
Khachatryan L, Burcat A, Dellinger B. The role of chlorine atoms and hydroxyl radicals in the formation of PCDDs from the oxidative pyrolysis of 2,4,6-trichlorophenol. INT J CHEM KINET 2009. [DOI: 10.1002/kin.20461] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
|
20
|
Bryukov MG, Knyazev VD, Gehling WM, Dellinger B. Kinetics of the gas-phase reaction of OH with chlorobenzene. J Phys Chem A 2009; 113:10452-9. [PMID: 19728723 DOI: 10.1021/jp9049186] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The kinetics of the reaction of hydroxyl radicals with chlorobenzene was studied experimentally using a pulsed laser photolysis/pulsed laser induced fluorescence technique over a wide range of temperatures, 298-670 K, and at pressures between 13.33 and 39.92 kPa. The bimolecular rate constants demonstrate different behavior at low and high temperatures. At room temperature, T = 298.8 +/- 1.5 K, the rate constant is equal to (6.02 +/- 0.34) x 10(-13) cm3 molecule(-1) s(-1); at high temperatures (474-670 K), the rate constant values are significantly lower and have a positive temperature dependence that can be described by an Arrhenius expression k1(T) = (1.01 +/- 0.35) x 10(-11) exp[(-2490 +/- 170 K)/T] cm3 molecule(-1) s(-1). This behavior is consistent with the low-temperature reaction being dominated by reversible addition and the high-temperature reaction representing abstraction and addition-elimination channels. The potential energy surface of the reaction was studied using quantum chemical methods, and a transition state theory model was developed for all reaction channels. The temperature dependences of the high-temperature rate constants obtained in calculations using the method of isodesmic reactions for transition states (IRTS) and the CBS-QB3 method are in very good agreement with experiment, with deviations smaller than the estimated experimental uncertainties. The G3//B3LYP-based calculated rate constants are in disagreement with the experimental values. The IRTS-based model was used to provide modified Arrhenius expressions for the temperature dependences of the rate constant for the abstraction and addition-elimination (Cl replacement) channels of the reaction.
Collapse
Affiliation(s)
- Mikhail G Bryukov
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, USA
| | | | | | | |
Collapse
|
21
|
Bacsik Z, Balogh N, Mink J. Indirect determination of molecular chlorine by fourier transform infrared spectrometry. APPLIED SPECTROSCOPY 2008; 62:339-341. [PMID: 18339245 DOI: 10.1366/000370208783759614] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Affiliation(s)
- Zoltán Bacsik
- Institute of Structural Chemistry, Chemical Research Center, Hungarian Academy of Sciences, Pusztaszeri út 59-67, H-1025 Budapest, Hungary.
| | | | | |
Collapse
|
22
|
Bryukov MG, Vidrine RG, Dellinger B. Temperature-Dependent Kinetics Study of the Gas-Phase Reactions of OH with n- and i-Propyl Bromide. J Phys Chem A 2007; 111:6197-203. [PMID: 17595069 DOI: 10.1021/jp072693c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
An experimental, temperature-dependent kinetics study of the gas-phase reactions of hydroxyl radical with n-propyl bromide, OH+n-C3H7Br-->products (reaction 1), and i-propyl bromide, OH+i-C3H7Br-->products (reaction 2), has been performed over wide ranges of temperatures 297-725 and 297-715 K, respectively, and at pressures between 6.67 and 26.76 kPa by a pulsed laser photolysis/pulsed laser-induced fluorescence technique. Data sets of absolute bimolecular rate coefficients obtained in this study for reactions 1 and 2 demonstrate no correlation with pressure and exhibit positive temperature dependencies that can be represented with modified three-parameter Arrhenius expressions within their corresponding experimental temperature ranges: k1(T)=(1.32x10(-17))T1.95 exp(+25/T) cm3 molecule(-1) s(-1) for reaction 1 and k2(T)=(1.56x10(-24))T4.18exp(+922/T) cm3 molecule(-1) s(-1) for reaction 2. The present results, which extend the current kinetics data base of reactions 1 and 2 to high temperatures, are compared with those from previous works. On the basis of the present data and available data from previous studies, the following bimolecular rate coefficient temperature dependencies can be recommended for the purpose of kinetic modeling: k1(T)=(1.89x10(-19))T2.54exp(+301/T) cm3 molecule-1 s-1 for reaction 1 in a temperature range 210-725 K, and k2(T)=(2.83x10(-21))T3.1exp(+521/T) cm3 molecule(-1) s(-1) and k2(T)=(4.54x10(-24))T4.03exp(+860/T) cm3 molecule(-1) s(-1) for reaction 2 in temperature ranges 210-480 and 297-715 K, respectively.
Collapse
Affiliation(s)
- Mikhail G Bryukov
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, USA
| | | | | |
Collapse
|
23
|
Knepp AM, Meloni G, Jusinski LE, Taatjes CA, Cavallotti C, Klippenstein SJ. Theory, measurements, and modeling of OH and HO2 formation in the reaction of cyclohexyl radicals with O2. Phys Chem Chem Phys 2007; 9:4315-31. [PMID: 17687479 DOI: 10.1039/b705934e] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The production of OH and HO(2) in Cl-initiated oxidation of cyclohexane has been measured using pulsed-laser photolytic initiation and continuous-laser absorption detection. The experimental data are modeled by master equation calculations that employ new G2(MP2)-like ab initio characterizations of important stationary points on the cyclo-C(6)H(11)O(2) surface. These ab initio calculations are a substantial expansion on previously published characterizations, including explicit consideration of conformational changes (chair-boat, axial-equatorial) and torsional potentials. The rate constants for the decomposition and ring-opening of cyclohexyl radical are also computed with ab initio based transition state theory calculations. Comparison of kinetic simulations based on the master equation results with the present experimental data and with literature determinations of branching fractions suggests adjustment of several transition state energies below their ab initio values. Simulations with the adjusted values agree well with the body of experimental data. The results once again emphasize the importance of both direct and indirect components of the kinetics for the production of both HO(2) and OH in radical + O(2) reactions.
Collapse
Affiliation(s)
- Adam M Knepp
- Combustion Research Facility, Mail Stop 9055, Sandia National Laboratories, Livermore, CA 94551-0969, USA
| | | | | | | | | | | |
Collapse
|
24
|
Allodi MA, Dunn ME, Livada J, Kirschner KN, Shields GC. Do Hydroxyl Radical−Water Clusters, OH(H2O)n, n = 1−5, Exist in the Atmosphere? J Phys Chem A 2006; 110:13283-9. [PMID: 17149847 DOI: 10.1021/jp064468l] [Citation(s) in RCA: 89] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
It has been speculated that the presence of OH(H2O)n clusters in the troposphere could have significant effects on the solar absorption balance and the reactivity of the hydroxyl radical. We have used the G3 and G3B3 model chemistries to model the structures and predict the frequencies of hydroxyl radical/water clusters containing one to five water molecules. The reaction between hydroxyl radical clusters and methane was examined as a function of water cluster size to gain an understanding of how cluster size affects the hydroxyl radical reactivity.
Collapse
Affiliation(s)
- Marco A Allodi
- Department of Chemistry, Hamilton College, Clinton, New York 13323, USA
| | | | | | | | | |
Collapse
|
25
|
Bryukov MG, Dellinger B, Knyazev VD. Kinetic study of the gas-phase reaction of OH with Br2. J Phys Chem A 2006; 110:9169-74. [PMID: 16854030 PMCID: PMC3171750 DOI: 10.1021/jp061038m] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
An experimental, temperature-dependent kinetic study of the gas-phase reaction of the hydroxyl radical with molecular bromine (reaction 1) has been performed by using a pulsed laser photolysis/pulsed-laser-induced fluorescence technique over a wide temperature range of 297-766 K, and at pressures between 6.68 and 40.29 kPa of helium. The experimental rate coefficients for reaction 1 demonstrate no correlation with pressure and exhibit a negative temperature dependence with a slight negative curvature in the Arrhenius plot. A nonlinear least-squares fit with two floating parameters of the temperature-dependent k(1)(T) data set using an equation of the form k(1)(T) = AT(n) yields the recommended expression k(1)(T) = (1.85 x 10(-9))T(-0.66) cm(3) molecule(-1) s(-1) for the temperature dependence of the reaction 1 rate coefficient. The potential energy surface (PES) of reaction 1 was investigated with use of quantum chemistry methods. The reaction proceeds through formation of a weakly bound OH...Br(2) complex and a PES saddle point with an energy below that of the reactants. Temperature dependence of the reaction rate coefficient was modeled by using the RRKM method on the basis of the calculated PES.
Collapse
Affiliation(s)
- Mikhail G Bryukov
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, USA
| | | | | |
Collapse
|
26
|
Shul’pin GB, Kudinov AR, Shul’pina LS, Petrovskaya EA. Oxidations catalyzed by osmium compounds. Part 1: Efficient alkane oxidation with peroxides catalyzed by an olefin carbonyl osmium(0) complex. J Organomet Chem 2006. [DOI: 10.1016/j.jorganchem.2005.10.028] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|
27
|
Bryukov MG, Dellinger B, Knyazev VD. Kinetics of the Gas-Phase Reaction of OH with HCl. J Phys Chem A 2005; 110:936-43. [PMID: 16419993 DOI: 10.1021/jp053615x] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
The reaction of hydroxyl radicals with hydrogen chloride (reaction 1) has been studied experimentally using a pulsed-laser photolysis/pulsed-laser-induced fluorescence technique over a wide range of temperatures, 298-1015 K, and at pressures between 5.33 and 26.48 kPa. The bimolecular rate coefficient data set obtained for reaction 1 demonstrates no dependence on pressure and exhibits positive temperature dependence that can be represented with modified three-parameter Arrhenius expression within the experimental temperature range: k1 = 3.20 x 10(-15)T0.99 exp(-62 K/T) cm3 molecule(-1) s(-1). The potential-energy surface has been studied using quantum chemical methods, and a transition-state theory model has been developed for the reaction 1 on the basis of calculations and experimental data. The model results in modified three-parameter Arrhenius expressions: k1 = 8.81 x 10(-16)T1.16 exp(58 K/T) cm3 molecule(-1) s(-1) for the temperature range 200-1015 K and k1 = 6.84 x 10(-19)T2.12 exp(646 K/T) cm3 molecule(-1) s(-1) for the temperature dependence of the reaction 1 rate coefficient extrapolation to high temperatures (500-3000 K). A temperature dependence of the rate coefficient of the Cl + H2O --> HCl + OH reaction has been derived on the basis of the experimental data, modeling, and thermochemical information.
Collapse
Affiliation(s)
- Mikhail G Bryukov
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, USA
| | | | | |
Collapse
|
28
|
Srinivasan NK, Su MC, Sutherland JW, Michael JV. Reflected Shock Tube Studies of High-Temperature Rate Constants for OH + CH4 → CH3 + H2O and CH3 + NO2 → CH3O + NO. J Phys Chem A 2005; 109:1857-63. [PMID: 16833517 DOI: 10.1021/jp040679j] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The reflected shock tube technique with multipass absorption spectrometric detection of OH radicals at 308 nm has been used to study the reactions OH + CH(4) --> CH(3) + H(2)O and CH(3) + NO(2) --> CH(3)O + NO. Over the temperature range 840-2025 K, the rate constants for the first reaction can be represented by the Arrhenius expression k = (9.52 +/- 1.62) x 10(-11) exp[(-4134 +/- 222 K)/T] cm(3) molecule(-1) s(-1). Since this reaction is important in both combustion and atmospheric chemistry, there have been many prior investigations with a variety of techniques. The present results extend the temperature range by 500 K and have been combined with the most accurate earlier studies to derive an evaluation over the extended temperature range 195-2025 K. A three-parameter expression describes the rate behavior over this temperature range, k = (1.66 x 10(-18))T(2.182) exp[(-1231 K)/T] cm(3) molecule(-1) s(-1). Previous theoretical studies are discussed, and the present evaluation is compared to earlier theoretical estimates. Since CH(3) radicals are a product of the reaction and could cause secondary perturbations in rate constant determinations, the second reaction was studied by OH radical production from the fast reactions CH(3)O --> CH(2)O + H and H + NO(2) --> OH + NO. The measured rate constant is 2.26 x 10(-11) cm(3) molecule(-1) s(-1) and is not dependent on temperature from 233 to 1700 K within experimental error.
Collapse
Affiliation(s)
- N K Srinivasan
- Chemistry Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
| | | | | | | |
Collapse
|