1
|
Chan YC, Nesbitt DJ. High-resolution infrared spectroscopy of jet cooled cyclobutyl in the α-CH stretch region: large-amplitude puckering dynamics in a 4-membered ring radical. Phys Chem Chem Phys 2024; 26:3081-3091. [PMID: 38180446 DOI: 10.1039/d3cp04812h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2024]
Abstract
Gas-phase cyclobutyl radical (c-C4H7) is generated at a rotational temperature of Trot = 26(1) K in a slit-jet discharge mixture of 70% Ne/30% He and 0.5-0.6% cyclobromobutane (c-C4H7Br). A fully rovibrationally resolved absorption spectrum of the α-CH stretch fundamental band between 3062.9 cm-1 to 3075.7 cm-1 is obtained and analyzed, yielding first precision structural and dynamical information for this novel radical species. The α-CH stretch band origin is determined to be 3068.7887(4) cm-1, which implies only a modest (≈0.8 cm-1) blue shift from rotationally unresolved infrared spectroscopic studies of cyclobutyl radicals in liquid He droplets [A. R. Brown, P. R. Franke and G. E. Douberly, J. Phys. Chem. A, 2017, 121, 7576-7587]. Of particular dynamical interest, a one-dimensional potential energy surface with respect to the ring puckering coordinate is computed at CCSD(T)/ANO2 level of theory and reveals a double minimum Cs puckered geometry, separated by an exceedingly shallow planar C2v transition state barrier (Ebarr ≈ 1 cm-1). Numerical solutions on this double minimum potential yield a zero-point energy for the ground state (Ezero-point ≈ 27 cm-1) greatly in excess of the interconversion barrier. This is indicative of highly delocalized, large amplitude motion of the four-membered ring structure, for which proper vibrationally averaging of the moment of inertia tensor reproduces the experimentally determined inertial defect remarkably well. Finally, intensity alternation in the experimental spectrum due to nuclear spin statistics upon exchange of three indistinguishable H atom pairs (IH = ½) matches Ka + Kc = even : odd = 36 : 28 predictions, implying that the unpaired electron in the radical center lies in an out-of-plane pπ orbital. Thus, high-resolution infrared spectroscopy provides first experimental confirmation of a shallow double minimum ring puckering potential with a highly delocalized ground state wave function peaked at a planar C2v transition state geometry consistent with a cyclobutyl π radical.
Collapse
Affiliation(s)
- Ya-Chu Chan
- JILA, University of Colorado Boulder and National Institute of Standards and Technology, Boulder, Colorado 80309, USA.
- Department of Chemistry, University of Colorado Boulder, Boulder, Colorado 80309, USA
| | - David J Nesbitt
- JILA, University of Colorado Boulder and National Institute of Standards and Technology, Boulder, Colorado 80309, USA.
- Department of Chemistry, University of Colorado Boulder, Boulder, Colorado 80309, USA
- Department of Physics, University of Colorado Boulder, Boulder, Colorado 80309, USA
| |
Collapse
|
2
|
Sun X, Pei Z, Li Z. High-Pressure-Limit Rate Coefficients for HO 2 Elimination Reactions of Hydroperoxyalkenylperoxy Radicals based on the Reaction Class Transition State Theory. ACS OMEGA 2022; 7:20020-20031. [PMID: 35721926 PMCID: PMC9202253 DOI: 10.1021/acsomega.2c01811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/24/2022] [Accepted: 05/19/2022] [Indexed: 06/15/2023]
Abstract
Thermokinetic parameters and transport parameters are of great importance to the combustion model and the reaction rate rules are of great importance to construct the combustion reaction mechanism for hydrocarbon fuels. The HO2 elimination reaction class for hydroperoxyalkenylperoxy radicals is one of the key reaction classes for olefin, for which the rate coefficients are lacking. Therefore, the rate coefficients and rate rules of the HO2 elimination reaction class for hydroperoxyalkenylperoxy radicals are studied in this work. The reaction class transition state theory (RC-TST) is used to calculate the rate coefficients. In addition, the HO2 elimination reaction class of hydroperoxyalkenylperoxy radicals is divided into four subclasses depending upon the type of H-Cβ bond that is broken in the reactant molecules, and the rate rules are calculated by taking the average of rate coefficients from a representative set of reactions in a subclass. The calculated kinetics data would be valuable for the construction of the combustion reaction mechanism for olefin.
Collapse
Affiliation(s)
- XiaoHui Sun
- School
of Energy Industry, Shanxi College of Technology, Shuozhou 036000, P. R. China
- College
of Chemistry, Sichuan University, Chengdu 610064, P. R. China
| | - ZhenYu Pei
- School
of Energy Industry, Shanxi College of Technology, Shuozhou 036000, P. R. China
| | - ZeRong Li
- College
of Chemistry, Sichuan University, Chengdu 610064, P. R. China
| |
Collapse
|
3
|
Yao X, Pang W, Li T, Shentu J, Li Z, Zhu Q, Li X. High-Pressure-Limit and Pressure-Dependent Rate Rules for Unimolecular Reactions Related to Hydroperoxy Alkyl Radicals in Normal-Alkyl Cyclohexane Combustion. 2. Cyclization Reaction Class. J Phys Chem A 2021; 125:8959-8977. [PMID: 34591473 DOI: 10.1021/acs.jpca.1c08085] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The hydroperoxy alkyl radicals are important intermediates in the low-temperature combustion for normal-alkyl cycloalkanes, and the cyclization reactions of hydroperoxy alkyl radicals to form cyclic ethers are responsible for a major fraction of the OH formation, which has the potential to promote ignition. In most of the previous modeling studies for normal-alkyl cycloalkane combustion, the kinetic data of the cyclization reactions in the detailed combustion mechanism were mainly taken from the analogous reactions in cyclohexane, methyl cyclohexane, and alkanes in published literature studies. In this work, the kinetics of the cyclization reaction class of hydroperoxy alkyl radicals in normal-alkyl cycloalkanes is studied, where the reaction class is divided into subclasses depending upon the ring size of the transition states, the types of the carbons on which the -OOH site is located and the types of the carbons on which the radical site is located, and the positions of the cyclization (on the alkyl side chain, on the cycle, or between the alkyl side chain and the cycle). Energy barriers and high-pressure-limit site rate constants and pressure-dependent rates for reactions in all subclasses are calculated, and rate rules for all subclasses are developed. The high-pressure-limit rate constants are determined from CBS-QB3 electronic structure calculations combined with canonical transition-state theory calculations, and pressure-dependent rate constants are calculated by using the Rice-Ramsberger-Kassel-Marcus/Master Equation theory at pressures varying from 0.01 to 100 atm. Comparisons of the rate constants for cyclization reactions of hydroperoxy alkyl cyclohexylperoxy radicals calculated in this work with the values of the corresponding reactions in some of the popular combustion mechanisms show that it is unreasonable to use the kinetic data of analogous reactions in alkanes, cyclohexanes, or smaller normal-alkyl cyclohexanes. Therefore, the accurate kinetic calculations and the construction of rate rules for normal-alkyl cycloalkanes are necessary and significant for the reliable modeling of the low-temperature combustion of normal-alkyl cyclohexanes.
Collapse
Affiliation(s)
- Xiaoxia Yao
- College of Chemical Engineering, Sichuan University, Chengdu 610065, PR China
| | - Weiqiang Pang
- Xi'an Modern Chemistry Research Institute, Xi'an 710065, China
| | - Tao Li
- College of Chemical Engineering, Sichuan University, Chengdu 610065, PR China
| | - Jiangtao Shentu
- College of Chemical Engineering, Sichuan University, Chengdu 610065, PR China
| | - Zerong Li
- College of Chemistry, Sichuan University, Chengdu 610064, PR China
| | - Quan Zhu
- College of Chemical Engineering, Sichuan University, Chengdu 610065, PR China
| | - Xiangyuan Li
- College of Chemical Engineering, Sichuan University, Chengdu 610065, PR China.,Engineering Research Center of Combustion and Cooling for Aerospace Power, Ministry of Education, Sichuan University, Chengdu, Sichuan 610065, PR China
| |
Collapse
|
4
|
Yao X, Pang W, Li T, Shentu J, Li Z, Zhu Q, Li X. High-Pressure-Limit and Pressure-Dependent Rate Rules for Unimolecular Reactions Related to Hydroperoxy Alkyl Radicals in Normal Alkyl Cyclohexane Combustion. 1. Concerted HO 2 Elimination Reaction Class and β -Scission Reaction Class. J Phys Chem A 2021; 125:8942-8958. [PMID: 34570492 DOI: 10.1021/acs.jpca.1c01122] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The reactions of the concerted HO2 elimination from alkyl peroxy radicals and the β-scission of the C-OOH bond from hydroperoxy alkyl radicals, which lead to the formation of olefins and HO2 radicals, are two important reaction classes that compete with the second O2 addition step of hydroperoxy alkyl radicals, which are responsible for the chain branching in the low-temperature oxidation of normal alkyl cycloalkanes. These two reaction classes are also believed to be responsible for the negative temperature coefficient behavior due to the formation of the relatively unreactive HO2 radical, which has the potential to inhibit ignition of normal alkyl cycloalkanes. In this work, the kinetics of the above two reaction classes in normal alkyl cycloalkanes are studied, where reactions in the concerted elimination class are divided into subclasses depending upon the types of carbons from which the H atom is eliminated and the positions of the reaction center (on the alkyl side chain or on the cycle), and the reactions in the β-scission reaction class are divided into subclasses depending upon the types of the carbons on which the radical is located and the positions of the reaction center. Energy barriers by using quantum chemical methods at the CBS-QB3 level, high-pressure-limit rate constants by using canonical transition state theory, and pressure-dependent rate constants at pressures from 0.01 to 100 atm by using Rice-Ramsberger-Kassel-Marcus/Master Equation theory are calculated for a representative set of reactions from methyl cyclohexane to n-butyl cyclohexane in each subclass, from which high-pressure-limit rate rules and pressure-dependent rate rules for each subclass are derived from the average rate constants of reactions within each subclass. A comparison of the rate constants for the reactions in the two reaction classes calculated in this work is made with the rate constants of the same reactions from available mechanisms published in the literature, where most of the rate constants are approximately estimated from analogous reactions in alkanes or small alkyl cyclohexanes, and it is found that a large difference may exist between them, indicating that the present work, which provides more accurate kinetic parameters and reasonable rate rules for these reaction classes, can be helpful to construct higher-accuracy mechanism models for normal alkyl cyclohexane combustion.
Collapse
Affiliation(s)
- Xiaoxia Yao
- College of Chemical Engineering, Sichuan University, Chengdu 610065, PR China
| | - Weiqiang Pang
- Xi'an Modern Chemistry Research Institute, Xi'an 710065, China
| | - Tao Li
- College of Chemical Engineering, Sichuan University, Chengdu 610065, PR China
| | - Jiangtao Shentu
- College of Chemical Engineering, Sichuan University, Chengdu 610065, PR China
| | - Zerong Li
- College of Chemistry, Sichuan University, Chengdu 610064, PR China
| | - Quan Zhu
- College of Chemical Engineering, Sichuan University, Chengdu 610065, PR China
| | - Xiangyuan Li
- College of Chemical Engineering, Sichuan University, Chengdu 610065, PR China.,Engineering Research Center of Combustion and Cooling for Aerospace Power, Ministry of Education, Sichuan University, Chengdu, Sichuan 610065, PR China
| |
Collapse
|
5
|
High-pressure limit rate rules for intramolecular H-migration reactions of α,β-hydroxyalkylperoxy radicals. Theor Chem Acc 2021. [DOI: 10.1007/s00214-021-02849-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
|
6
|
Mertens LA, Manion JA. Kinetics of isopropanol decomposition and reaction with H atoms from shock tube experiments and rate constant optimization using the method of uncertainty minimization using polynomial chaos expansions (MUM‐PCE). INT J CHEM KINET 2020. [DOI: 10.1002/kin.21428] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
- Laura A. Mertens
- Chemical Sciences Division National Institute of Standards and Technology Gaithersburg Maryland
| | - Jeffrey A. Manion
- Chemical Sciences Division National Institute of Standards and Technology Gaithersburg Maryland
| |
Collapse
|
7
|
Sun Y, Zhou CW, Somers KP, Curran HJ. An ab Initio/Transition State Theory Study of the Reactions of Ċ 5H 9 Species of Relevance to 1,3-Pentadiene, Part II: Pressure Dependent Rate Constants and Implications for Combustion Modeling. J Phys Chem A 2020; 124:4605-4631. [PMID: 32396376 DOI: 10.1021/acs.jpca.0c02244] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The temperature- and pressure-dependence of rate constants for several radicals and unsaturated hydrocarbons reactions (1,3-C5H8/1,4-C5H8/cyC5H8 + Ḣ, C2H4 + Ċ3H5-a, C3H6 + Ċ2H3) are analyzed in this paper. The abstraction reactions of these systems are also calculated and compared with available literature data. Ċ5H9 radicals can be produced via Ḣ atom addition reactions to the pentadiene isomers and cyclopentene, and also by H-atom abstraction reactions from 1- and 2-pentene and cyclopentane. Comprehensive Ċ5H9 potential energy surface (PES) analyses and high-pressure limiting rate constants for related reactions have been explored in part I of this work ( J. Phys. Chem. A 2019, 123 (22), 9019-9052). In this work, a chemical kinetic model is constructed based on the computed thermochemistry and high-pressure limiting rate constants from part I, to further understand the chemistry of different C5H8 molecules. The most important channels for these addition reactions are discussed in the present work based on reaction pathway analyses. The dominant reaction pathways for these five systems are combined together to generate a simplified Ċ5H9 PES including nine reactants, 25 transition states (TSs), and nine products. Spin-restricted single point energies are calculated for radicals and TSs on the simplified PES at the ROCCSD(T)/aug-cc-pVTZ level of theory with basis set corrections from MP2/aug-cc-pVXZ (where X = T and Q). Temperature- and pressure-dependent rate constants are calculated using RRKM theory with a Master Equation analysis, with restricted energies used for minima on the simplified Ċ5H9 PES and unrestricted energies for other species, over a temperature range of 300-2000 K and in the pressure range 0.01-100 atm. The rate constants calculated are in good agreement with those in the literature. The chemical kinetic model is updated with pressure-dependent rate constants and is used to simulate the species concentration profiles for Ḣ atom addition to cyclopentane and cyclopentene. Through detailed analyses and comparisons, this model can reproduce the experimental measurements of species qualitatively and quantitatively with reasonably good agreement.
Collapse
Affiliation(s)
- Yanjin Sun
- Combustion Chemistry Centre, National University of Ireland, Galway, Ireland
| | - Chong-Wen Zhou
- Combustion Chemistry Centre, National University of Ireland, Galway, Ireland.,School of Energy and Power Engineering, Beihang University, Beijing 100191, P. R. China
| | - Kieran P Somers
- Combustion Chemistry Centre, National University of Ireland, Galway, Ireland
| | - Henry J Curran
- Combustion Chemistry Centre, National University of Ireland, Galway, Ireland
| |
Collapse
|
8
|
Xiao F, Sun X, Li Z, Li X. Theoretical Study of Radical-Molecule Reactions with Negative Activation Energies in Combustion: Hydroxyl Radical Addition to Alkenes. ACS OMEGA 2020; 5:12777-12788. [PMID: 32548462 PMCID: PMC7288374 DOI: 10.1021/acsomega.0c00400] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/29/2020] [Accepted: 05/15/2020] [Indexed: 06/11/2023]
Abstract
Many of the radical-molecule reactions are nonelementary reactions with negative activation energies, which usually proceed through two steps. They exist extensively in the atmospheric chemistry and hydrocarbon fuel combustion, so they are extensively studied both theoretically and experimentally. At the same time, various models, such as a two transition state model, a steady-state model, an equilibrium-state model, and a direct elementary dynamics model are proposed to get the kinetic parameters for the overall reaction. In this paper, a conversion temperature T C1 is defined as the temperature at which the standard molar Gibbs free energy change of the formation of the reaction complex is equal to zero, and it is found that when T ≫ T C1, the direct elementary dynamics model with an inclusion of the tunneling correction of the second step reaction is applicable to calculate the overall reaction rate constants for this kind of reaction system. The reaction class of hydroxyl radical addition to alkenes is chosen as the objects of this study, five reactions are chosen as the representative for the reaction class, and their single-point energies are calculated using the method of CCSD(T)/CBS, and it is shown that the highest conversion temperature for the five reactions is 139.89 K, far below the usual initial low-temperature (550 K) oxidation chemistry of hydrocarbon fuels; therefore, the steady-state approximation method is applicable. All geometry optimizations are performed at the BH&HLYP/6-311+G(d,p) level, and the result shows that the geometric parameters in the reaction centers are conserved; hence, the isodesmic reaction method is applicable to this reaction class. To validate the accuracy of this scheme, a comparison of electronic energy difference at the BH&HLYP/6-311+G(d,p) level and the corrected electronic energy difference with the electronic energy difference at the CCSD(T)/CBS level is performed for the five representative reactions, and it is shown that the maximum absolute deviation of electronic energy difference can be reduced from 2.54 kcal·mol-1 before correction to 0.58 kcal·mol-1 after correction, indicating that the isodesmic reaction method is applicable for the accurate calculation of the kinetic parameters for large-size molecular systems with a negative activation energy reaction. The overall rate constants for 44 reactions of the reaction class of hydroxyl radical addition to alkenes are calculated using the transition-state theory in combination with the isodesmic correction scheme, and high-pressure limit rate rules for the reaction class are developed. In addition, the thermodynamic parameter is calculated and the results indicate that our dynamics model is applicable for our studied reaction class. A chemical kinetic modeling and sensitivity analysis using the calculated kinetic data is performed for the combustion of ethene, and the results indicate the studied reaction is important for the low-to-medium temperature combustion modeling of ethene.
Collapse
Affiliation(s)
- FengXia Xiao
- College
of Chemistry, Sichuan University, Chengdu 610064, P. R. China
| | - XiaoHui Sun
- College
of Chemical Engineering, Sichuan University, Chengdu 610065, P. R. China
| | - ZeRong Li
- College
of Chemistry, Sichuan University, Chengdu 610064, P. R. China
| | - XiangYuan Li
- College
of Chemical Engineering, Sichuan University, Chengdu 610065, P. R. China
- Engineering
Research Center of Combustion and Cooling for Aerospace Power, Ministry
of Education, Sichuan University, Chengdu, Sichuan 610065, P. R. China
| |
Collapse
|
9
|
Cao XM, Li ZR, Wang JB, Li XY. Rate rules for hydrogen abstraction reaction kinetics of alkenes from allylic sites by HO2 radical. COMPUT THEOR CHEM 2020. [DOI: 10.1016/j.comptc.2020.112795] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
10
|
Sun Y, Zhou CW, Somers KP, Curran HJ. Ab Initio/Transition-State Theory Study of the Reactions of Ċ 5H 9 Species of Relevance to 1,3-Pentadiene, Part I: Potential Energy Surfaces, Thermochemistry, and High-Pressure Limiting Rate Constants. J Phys Chem A 2019; 123:9019-9052. [PMID: 31566374 DOI: 10.1021/acs.jpca.9b06628] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
In this study, the reactions of Ċ5H9 radicals are theoretically investigated, with a particular emphasis on hydrogen atom addition reactions to 1,3-pentadiene (C5H8) to form Ċ5H9 radicals, although the subsequent isomerization and decomposition reactions of the Ċ5H9 radicals are also of direct relevance to the radicals formed from the pyrolysis and oxidation of species including pentene and cyclopentane. Moreover, H-atom abstraction reactions by hydrogen atoms from 1,3-pentadiene are also investigated. The geometries and frequencies of 63 potential energy surface (PES) minima and 88 transition states are optimized at the ωB97XD/aug-cc-pVTZ level of theory. Spin-unrestricted open-shell single-point energies for all the species are calculated at the CCSD(T)/aug-cc-pVTZ level of theory with basis set corrections from MP2/aug-cc-pVXZ (where X = T and Q). A one-dimensional hindered rotor treatment is employed for torsional modes, with the M06-2X/6-311++G(D,P) method used to compute the potential energy as a function of the dihedral angle. The high-pressure limiting rate constants and the thermochemical properties for C5 species are calculated using the Master Equation System Solver (MESS) with conventional transition-state theory and comparisons made with existing available literature data. A hydrogen atom can add to the terminal carbon atom of 1,3-pentadiene to form the 2,4-Ċ5H9 radical and/or the internal carbon atoms to form 2,5-Ċ5H9, 1,4-Ċ5H9, and 1,3-Ċ5H9 radicals. Among the four entrance channels for Ḣ atom addition reactions, the formation of 2,4-Ċ5H9 and 1,3-Ċ5H9 radicals is more exothermic in comparison to the other Ċ5H9 isomers (2,5-Ċ5H9, 1,4-Ċ5H9) because of the resonantly stabilized allylic structure. Consequently, the formation of the former is generally dominant in terms of barrier heights. Ḣ atom addition reactions to 1,3-pentadiene are compared to available C3-C5 alkenes and dienes, with external addition calculated to be kinetically favored over internal addition. However, the correlation between heats of formation and energy barriers for Ḣ atom addition to 1,2-dienes is different from that for 1,3- and 1,4-dienes. Hydrogen atom addition and abstraction rate constants are also compared for 1,3-pentadiene, with addition found to be dominant. The subsequent unimolecular reactions on the Ċ5H9 PES are found to be highly complex with reactions taking place on a multiple-well multiple-channel PES. For clarity, the reaction mechanism and kinetics of each Ċ5H9 radical are discussed individually in terms of the computed enthalpy of the reaction and activation, the transition-state structure/reaction class, and also in terms of the combustion species for which the reactions are of potential importance. The reactions on the Ċ5H9 PES are divided into three reaction classes (H-shift isomerization, cycloaddition, and β-scission reactions), and the reactivity-structure-based estimation rules for energy barriers are derived for these three reaction classes and compared to literature results for alkyl radicals.
Collapse
Affiliation(s)
- Yanjin Sun
- Combustion Chemistry Centre, School of Chemistry, Martin Ryan Institute MaREI , National University of Ireland , Galway H91 TK33 , Ireland
| | - Chong-Wen Zhou
- Combustion Chemistry Centre, School of Chemistry, Martin Ryan Institute MaREI , National University of Ireland , Galway H91 TK33 , Ireland.,School of Energy and Power Engineering , Beihang University , Beijing 100191 , P. R. China
| | - Kieran P Somers
- Combustion Chemistry Centre, School of Chemistry, Martin Ryan Institute MaREI , National University of Ireland , Galway H91 TK33 , Ireland
| | - Henry J Curran
- Combustion Chemistry Centre, School of Chemistry, Martin Ryan Institute MaREI , National University of Ireland , Galway H91 TK33 , Ireland
| |
Collapse
|
11
|
Power J, Somers KP, Zhou CW, Peukert S, Curran HJ. Theoretical, Experimental, and Modeling Study of the Reaction of Hydrogen Atoms with 1- and 2-Pentene. J Phys Chem A 2019; 123:8506-8526. [PMID: 31502844 DOI: 10.1021/acs.jpca.9b06378] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Alkyl radicals are prominent in combustion chemistry as they are formed by hydrocarbon decomposition or from a radical attack on hydrocarbons. Accurate determinations of the thermochemistry and kinetics of their unimolecular isomerization and decomposition reactions and related addition reactions of alkenes are therefore important in simulating the combustion chemistry of virtually all hydrocarbon fuels. In this work, a comprehensive potential energy surface (PES) for Ḣ-atom addition to and abstraction from 1- and 2-pentene, and the subsequent C-C and C-H β-scission reactions, and H-atom transfer reactions has been considered. Thermochemical values for the species on the Ċ5H11 PES were calculated as a function of temperature (298-2000 K), with enthalpies of formation determined using a network of isodesmic reactions. High-pressure limiting and pressure-dependent rate constants were calculated using the Rice-Ramsperger-Kassel-Marcus theory coupled with a one-dimensional master equation. As a validation of our theoretical results, hydrogen atomic resonance absorption spectrometry experiments were performed on the Ḣ-atom addition and abstraction reactions of 1- and 2-pentene. By incorporating our calculations into a detailed chemical kinetic model (AramcoMech 3.0), excellent agreement with these experiments is observed. The theoretical results are further validated via a comprehensive series of simulations of literature data. Our a priori model is found to reproduce important absolute species concentrations and product ratios reported therein.
Collapse
Affiliation(s)
- Jennifer Power
- Combustion Chemistry Centre, School of Chemistry & Ryan Institute , National University of Ireland , Galway H91TK33 , Ireland
| | - Kieran P Somers
- Combustion Chemistry Centre, School of Chemistry & Ryan Institute , National University of Ireland , Galway H91TK33 , Ireland
| | - Chong-Wen Zhou
- Combustion Chemistry Centre, School of Chemistry & Ryan Institute , National University of Ireland , Galway H91TK33 , Ireland.,School of Energy and Power Engineering , Beihang University , Beijing 100191 , P. R. China
| | - Sebastian Peukert
- Institute for Combustion and Gas Dynamics-Reactive Fluids , University of Duisburg-Essen , 47058 Duisburg , Germany
| | - Henry J Curran
- Combustion Chemistry Centre, School of Chemistry & Ryan Institute , National University of Ireland , Galway H91TK33 , Ireland
| |
Collapse
|
12
|
Kozliak E, Sulkes M, Alhroub I, Kubátová A, Andrianova A, Seames W. Influence of early stages of triglyceride pyrolysis on the formation of PAHs as coke precursors. Phys Chem Chem Phys 2019; 21:20189-20203. [PMID: 31486462 DOI: 10.1039/c9cp02025j] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Molecular beam (MB) time-of-flight mass spectrometry has been used to investigate thermal decomposition of triolein, to reveal the mechanisms of low temperature soot/coke formation characteristic for triglycerides (TGs). Mass detected pyrolysis products were observed at incremented temperatures using both VUV single photon ionization (general product detection) and REMPI based selective detection of aromatic products. To augment the simple mass characterizations, we have employed stoichiometric considerations; we have supplemented the analysis further by using the detailed information available from product analysis of batch reactor TG cracking. Both the VUV photoionization and batch reactor studies indicated that formation of C7-sized stable products is a marker of significant triolein decomposition that is coupled with PAH formation. A significant fraction of the C7 species observed likely formed as a result of a C-C bond scission at the allylic position to the ω-9 double bond of oleic acid. REMPI detection indicated a high specificity for PAH formation at three distinct molecular weight values, 276, 352 and 444 amu (the latter being a fullerene precursor). The stoichiometric analysis has shown that these PAHs likely arise from condensation reactions of either C7- or C8-sized fragments (three, four and five, respectively). The C8-sized intermediate would become essential whenever the PAH product of C7 fragment condensation contained an odd number of carbon atoms, resulting in a less stable aromatic structure with an incomplete double bond conjugation. MB experiments involving either addition or in situ generation of hydrogen resulted in an enhancement of lower molecular weight PAH formation, i.e., a decrease in the effective number of condensing fragments. In contrast, an increase in temperature yielded the opposite effect.
Collapse
|
13
|
Chemical Kinetics of Hydrogen Atom Abstraction from Propargyl Sites by Hydrogen and Hydroxy Radicals. Int J Mol Sci 2019; 20:ijms20133227. [PMID: 31262079 PMCID: PMC6650822 DOI: 10.3390/ijms20133227] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2019] [Revised: 06/26/2019] [Accepted: 06/27/2019] [Indexed: 01/02/2023] Open
Abstract
Hydrogen atom abstraction from propargyl C-H sites of alkynes plays a critical role in determining the reactivity of alkyne molecules and understanding the formation of soot precursors. This work reports a systematic theoretical study on the reaction mechanisms and rate constants for hydrogen abstraction reactions by hydrogen and hydroxy radicals from a series of alkyne molecules with different structural propargyl C-H atoms. Geometry optimizations and frequency calculations for all species are performed at M06-2X/cc-pVTZ level of theory and the hindered internal rotations are also treated at this level. The high-level W1BD and CCSD(T)/CBS theoretical calculations are used as a benchmark for a series of DFT calculations toward the selection of accurate DFT functionals for large reaction systems in this work. Based on the quantum chemistry calculations, rate constants are computed using the canonical transition state theory with tunneling correction and the treatment of internal rotations. The effects of the structure and reaction site on the energy barriers and rate constants are examined systematically. To the best of our knowledge, this work provides the first systematic study for one of the key initiation abstraction reactions for compounds containing propargyl hydrogen atoms.
Collapse
|
14
|
Sun X, Zong W, Wang J, Li Z, Li X. Pressure-dependent rate rules for cycloaddition, intramolecular H-shift, and concerted elimination reactions of alkenyl peroxy radicals at low temperature. Phys Chem Chem Phys 2019; 21:10693-10705. [PMID: 31086861 DOI: 10.1039/c9cp01207a] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The reactions of cycloaddition, intramolecular H-shift and concerted elimination of alkenyl peroxy radicals are three kinds of important reactions in the low temperature combustion of alkenes. In this study, the cycloaddition reactions are divided into classes considering endo-cycloaddition, exo-cycloaddition and the size of the transition states; the intramolecular H-shift reactions are divided into classes depending upon the ring size of the transition states and the type of C-H bonds from which the hydrogen atom is transferred; the concerted elimination reactions are divided into classes according to the type of H-CβCαOO bond that is broken. All geometry optimizations are performed at the B3LYP/6-31G(2df,p) level. With the electronic structure calculations being performed using the composite Gaussian-4 (G4) method, high pressure limit rate constants and pressure-dependent rate constants at pressures varying from 0.01 to 100 atm are calculated by using canonical transition state theory and the Rice-Ramsberger-Kassel-Marcus/master equation method, respectively. All rate constants are given in the form of the modified Arrhenius expression. The high pressure limit rate rules and the pressure-dependent rate rules are derived by averaging the rate constants of a representative set of reactions in each class. The results show that the rate rules for these three classes of reactions have a large uncertainty and the impact of the pressure on the rate constants increases as temperature increases.
Collapse
Affiliation(s)
- Xiaohui Sun
- School of Chemical Engineering, Sichuan University, Chengdu, Sichuan 610065, China.
| | - Wengang Zong
- School of Chemical Engineering, Sichuan University, Chengdu, Sichuan 610065, China.
| | - Jingbo Wang
- School of Chemical Engineering, Sichuan University, Chengdu, Sichuan 610065, China.
| | - Zerong Li
- College of Chemistry, Sichuan University, Chengdu, Sichuan 610064, China.
| | - Xiangyuan Li
- School of Chemical Engineering, Sichuan University, Chengdu, Sichuan 610065, China.
| |
Collapse
|
15
|
|
16
|
Mertens LA, Awan IA, Sheen DA, Manion JA. Evaluated Site-Specific Rate Constants for Reaction of Isobutane with H and CH3: Shock Tube Experiments Combined with Bayesian Model Optimization. J Phys Chem A 2018; 122:9518-9541. [DOI: 10.1021/acs.jpca.8b08781] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Laura A. Mertens
- Chemical Sciences Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8320, United States
| | - Iftikhar A. Awan
- Chemical Sciences Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8320, United States
| | - David A. Sheen
- Chemical Sciences Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8320, United States
| | - Jeffrey A. Manion
- Chemical Sciences Division, National Institute of Standards and Technology, Gaithersburg, Maryland 20899-8320, United States
| |
Collapse
|
17
|
Wang X, Liu J, Yu Z, Guo M, Tang X, Wang G. Desulfonylation-Initiated Distal Alkenyl Migration in Copper-Catalyzed Alkenylation of Unactivated Alkenes. Org Lett 2018; 20:6516-6519. [DOI: 10.1021/acs.orglett.8b02840] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Xiaoyang Wang
- Tianjin Key Laboratory of Molecular Optoelectronic Science, Department of Chemistry, School of Science, Tianjin University, Tianjin 300072, P. R. China
| | - Jing Liu
- Tianjin Key Laboratory of Molecular Optoelectronic Science, Department of Chemistry, School of Science, Tianjin University, Tianjin 300072, P. R. China
| | - Ze Yu
- Tianjin Key Laboratory of Molecular Optoelectronic Science, Department of Chemistry, School of Science, Tianjin University, Tianjin 300072, P. R. China
| | - Minjie Guo
- Institute for Molecular Design and Synthesis, School of Pharmaceutical Science and Technology, Tianjin University, Tianjin 300072, P. R. China
| | - Xiangyang Tang
- Tianjin Key Laboratory of Molecular Optoelectronic Science, Department of Chemistry, School of Science, Tianjin University, Tianjin 300072, P. R. China
| | - Guangwei Wang
- Tianjin Key Laboratory of Molecular Optoelectronic Science, Department of Chemistry, School of Science, Tianjin University, Tianjin 300072, P. R. China
| |
Collapse
|
18
|
Mai TVT, Ratkiewicz A, Le A, Duong MV, Truong TN, Huynh LK. On-the-fly kinetics of hydrogen abstraction from polycyclic aromatic hydrocarbons by methyl/ethyl radicals. Phys Chem Chem Phys 2018; 20:23578-23592. [PMID: 30188552 DOI: 10.1039/c8cp03718c] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
This work provides a rigorous procedure, within the framework of the Reaction Class Transition State Theory (RC-TST) and the Structure-Activity Relationship (SAR), for predicting reliable thermal rate constants on-the-fly for hydrogen abstraction reactions by methyl/ethyl radicals from Polycyclic Aromatic Hydrocarbons (PAHs) in a temperature range of 300-3000 K. All necessary RC-TST parameters were derived from ab initio calculations for a representative set of 36 reactions on which different error analyses and comparisons with available literature data were carried out. In addition to the good agreement between the RC-TST rate constants and the literature data, the detailed error analyses show that RC-TST/SAR, utilizing either the Linear Energy Relationship (LER) where only the reaction energy is needed or Barrier Height Grouping (BHG) where no additional data is needed, can predict the thermal rate constants for any reaction in the title reaction class with an average systematic error of less than 50% when compared to the explicit rate calculations. Therefore, the constructed RC-TST procedure can be confidently used to obtain reliable rate constants on the fly in an attempt to effectively construct detailed kinetic mechanisms for PAH-related fuels.
Collapse
Affiliation(s)
- Tam V-T Mai
- Institute for Computational Science and Technology, Ho-Chi-Minh City, Vietnam
| | | | | | | | | | | |
Collapse
|
19
|
Le XT, Mai TVT, Lin KC, Huynh LK. Low Temperature Oxidation Kinetics of Biodiesel Molecules: Rate Rules for Concerted HO2 Elimination from Alkyl Ester Peroxy Radicals. J Phys Chem A 2018; 122:8259-8273. [DOI: 10.1021/acs.jpca.8b05070] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Xuan T. Le
- Institute for Computational Science and Technology at Ho Chi Minh City, Ho Chi Minh City, Vietnam
- University of Science, Vietnam National University—HCMC, Ho Chi Minh City, Vietnam
| | - Tam V.-T. Mai
- Institute for Computational Science and Technology at Ho Chi Minh City, Ho Chi Minh City, Vietnam
- University of Science, Vietnam National University—HCMC, Ho Chi Minh City, Vietnam
| | - Kuang C. Lin
- Department of Engineering and System Science, National Tsing Hua University, Hsinchu, 30013, Taiwan
| | - Lam K. Huynh
- International University, Vietnam National University—HCMC, Ho Chi Minh City, Vietnam
| |
Collapse
|
20
|
Mertens LA, Manion JA. β-Bond Scission and the Yields of H and CH 3 in the Decomposition of Isobutyl Radicals. J Phys Chem A 2018; 122:5418-5436. [PMID: 29738670 DOI: 10.1021/acs.jpca.8b01194] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The relative rates of C-C and C-H β-scission reactions of isobutyl radicals (2-methylprop-1-yl, C4H9) were investigated with shock tube experiments at temperatures of (950 to 1250) K and pressures of (200 to 400) kPa. We produced isobutyl radicals from the decomposition of dilute mixtures of isopentylbenzene and observed the stable decomposition products, propene and isobutene. These alkenes are characteristic of C-C and C-H bond scission, respectively. Propene was the main product, approximately 30 times more abundant than isobutene, indicating that C-C β-scission is the primary pathway. Uncertainty in the ratio of [isobutene]/[propene] from isobutyl decomposition is mainly due to a small amount of side chemistry, which we account for using a kinetics model based on JetSurF 2.0. Our data are well-described after adding chemistry specific to our system and adjusting some rate constants. We compare our data to other commonly used kinetics models: JetSurF 2.0, AramcoMech 2.0, and multiple models from Lawrence Livermore National Laboratory (LLNL). With the kinetics model, we have determined an upper limit of 3.0% on the branching fraction for C-H β-scission in the isobutyl radical for the temperatures and pressures of our experiments. While this agrees with previous high quality experimental results, many combustion kinetics models assume C-H branching values above this upper limit, possibly leading to large systematic inaccuracies in model predictions. Some kinetics models additionally assume contributions from 1,2-H shift reactions-which for isobutyl would produce the same products as C-H β-scission-and our upper limit includes possible involvement of such reactions. We suggest kinetics models should be updated to better reflect current experimental measurements.
Collapse
Affiliation(s)
- Laura A Mertens
- Chemical Sciences Division , National Institute of Standards and Technology , Gaithersburg , Maryland 20899-8320 , United States
| | - Jeffrey A Manion
- Chemical Sciences Division , National Institute of Standards and Technology , Gaithersburg , Maryland 20899-8320 , United States
| |
Collapse
|
21
|
Van de Vijver R, Sabbe MK, Reyniers MF, Van Geem KM, Marin GB. Ab initio derived group additivity model for intramolecular hydrogen abstraction reactions. Phys Chem Chem Phys 2018. [PMID: 29517772 DOI: 10.1039/c7cp07771h] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A set of group additivity values for intramolecular hydrogen abstraction reactions of alkanes, alkenes and alkynes is reported. Calculating 448 reaction rate coefficients at the CBS-QB3 level of theory for 1-2 up to 1-7 hydrogen shift reactions allowed the estimation of ΔGAV° values for 270 groups. The influence of substituents on (1) the attacking radical, (2) the attacked carbon atom, and (3) the carbon chain between the attacking and attacked reactive atom has been systematically studied. Substituents have been varied between hydrogen atoms and sp3, sp2 and sp hybridized carbon atoms. It has been assumed that substituents further away from the reactive atoms or their connecting carbon chain have negligible influences on the kinetics. This group additivity model is applicable to a wide variety of reactions in the 300-1800 K temperature range. Correlations for tunneling coefficients have been generated which are complementary to the ΔGAV°'s to obtain accurate rate coefficients without the need for imaginary frequencies or electronic energies of activation. These correlations depend on the temperature and activation energy of the exothermic step. The group additivity model has been successfully applied to a test set of reactions also calculated at the CBS-QB3 level of theory. A mean absolute deviation of 1.18 to 1.71 has been achieved showing a good overall accuracy of the model.
Collapse
Affiliation(s)
- Ruben Van de Vijver
- Ghent University, Laboratory for Chemical Technology, Technologiepark 914, Ghent, Belgium.
| | | | | | | | | |
Collapse
|
22
|
Alhroub I, Kozliak E, Kubátová A, Sulkes M. PAH/Aromatic Tar and Coke Precursor Formation in the Early Stages of Triglyceride (Triolein) Pyrolysis. J Phys Chem A 2018. [DOI: 10.1021/acs.jpca.7b11340] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Ibrahim Alhroub
- Chemistry Department, Tulane University, New Orleans, Louisiana 70118, United States
| | - Evguenii Kozliak
- Department of Chemistry, University of North Dakota, Grand Forks, North Dakota 58202, United States
| | - Alena Kubátová
- Department of Chemistry, University of North Dakota, Grand Forks, North Dakota 58202, United States
| | - Mark Sulkes
- Chemistry Department, Tulane University, New Orleans, Louisiana 70118, United States
| |
Collapse
|
23
|
Affiliation(s)
- Jeffrey A. Manion
- Chemical Sciences Division; National Institute of Standards and Technology; Gaithersburg MD 20899-8320
| | - Iftikhar A. Awan
- Chemical Sciences Division; National Institute of Standards and Technology; Gaithersburg MD 20899-8320
| |
Collapse
|
24
|
Bao JL, Zhang X, Truhlar DG. Predicting pressure-dependent unimolecular rate constants using variational transition state theory with multidimensional tunneling combined with system-specific quantum RRK theory: a definitive test for fluoroform dissociation. Phys Chem Chem Phys 2018; 18:16659-70. [PMID: 27273734 DOI: 10.1039/c6cp02765b] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Understanding the falloff in rate constants of gas-phase unimolecular reaction rate constants as the pressure is lowered is a fundamental problem in chemical kinetics, with practical importance for combustion, atmospheric chemistry, and essentially all gas-phase reaction mechanisms. In the present work, we use our recently developed system-specific quantum RRK theory, calibrated by canonical variational transition state theory with small-curvature tunneling, combined with the Lindemann-Hinshelwood mechanism, to model the dissociation reaction of fluoroform (CHF3), which provides a definitive test for falloff modeling. Our predicted pressure-dependent thermal rate constants are in excellent agreement with experimental values over a wide range of pressures and temperatures. The present validation of our methodology, which is able to include variational transition state effects, multidimensional tunneling based on the directly calculated potential energy surface along the tunneling path, and torsional and other vibrational anharmonicity, together with state-of-the-art reaction-path-based direct dynamics calculations, is important because the method is less empirical than models routinely used for generating full mechanisms, while also being simpler in key respects than full master equation treatments and the full reduced falloff curve and modified strong collision methods of Troe.
Collapse
Affiliation(s)
- Junwei Lucas Bao
- Department of Chemistry, Chemical Theory Center, and Supercomputing Institute, University of Minnesota, Minneapolis, Minnesota 55455-0431, USA.
| | - Xin Zhang
- State Key Laboratory of Chemical Resource Engineering, Institute of Materia Medica, College of Science, Beijing University of Chemical Technology, Beijing, 100029, P. R. China. and Department of Chemistry, Chemical Theory Center, and Supercomputing Institute, University of Minnesota, Minneapolis, Minnesota 55455-0431, USA.
| | - Donald G Truhlar
- Department of Chemistry, Chemical Theory Center, and Supercomputing Institute, University of Minnesota, Minneapolis, Minnesota 55455-0431, USA.
| |
Collapse
|
25
|
Zhang H, Zhang X, Truhlar DG, Xu X. Nonmonotonic Temperature Dependence of the Pressure-Dependent Reaction Rate Constant and Kinetic Isotope Effect of Hydrogen Radical Reaction with Benzene Calculated by Variational Transition-State Theory. J Phys Chem A 2017; 121:9033-9044. [PMID: 29095614 DOI: 10.1021/acs.jpca.7b09374] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The reaction between H and benzene is a prototype for reactions of radicals with aromatic hydrocarbons. Here we report calculations of the reaction rate constants and the branching ratios of the two channels of the reaction (H addition and H abstraction) over a wide temperature and pressure range. Our calculations, obtained with an accurate potential energy surface, are based on variational transition-state theory for the high-pressure limit of the addition reaction and for the abstraction reaction and on system-specific quantum Rice-Ramsperger-Kassel theory calibrated by variational transition-state theory for pressure effects on the addition reaction. The latter is a very convenient way to include variational effects, corner-cutting tunneling, and anharmonicity in falloff calculations. Our results are in very good agreement with the limited experimental data and show the importance of including pressure effects in the temperature interval where the mechanism changes from addition to abstraction. We found a negative temperature effect of the total reaction rate constants at 1 atm pressure in the temperature region where experimental data are missing and accurate theoretical data were previously missing as well. We also calculated the H + C6H6/C6D6 and D + C6H6/C6D6 kinetic isotope effects, and we compared our H + C6H6 results to previous theoretical data for H + toluene. We report a very novel nonmonotonic dependence of the kinetic isotope effect on temperature. A particularly striking effect is the prediction of a negative temperature dependence of the total rate constant over 300-500 K wide temperature ranges, depending on the pressure but generally in the range from 600 to 1700 K, which includes the temperature range of ignition in gasoline engines, which is important because aromatics are important components of common fuels.
Collapse
Affiliation(s)
- Hui Zhang
- State Key Laboratory of Chemical Resource Engineering, Institute of Materia Medica, College of Science, Beijing University of Chemical Technology , Beijing 100029, P. R. China.,Center for Combustion Energy and Department of Thermal Engineering, Tsinghua University , Beijing 100084, P. R. China
| | - Xin Zhang
- State Key Laboratory of Chemical Resource Engineering, Institute of Materia Medica, College of Science, Beijing University of Chemical Technology , Beijing 100029, P. R. China
| | - Donald G Truhlar
- Department of Chemistry, Chemical Theory Center, and Minnesota Supercomputing Institute, University of Minnesota , Minneapolis, Minnesota 55455-0431, United States
| | - Xuefei Xu
- Center for Combustion Energy and Department of Thermal Engineering, Tsinghua University , Beijing 100084, P. R. China
| |
Collapse
|
26
|
Van Hoomissen DJ, Vyas S. 1,2-Fluorine Radical Rearrangements: Isomerization Events in Perfluorinated Radicals. J Phys Chem A 2017; 121:8675-8687. [DOI: 10.1021/acs.jpca.7b08895] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
| | - Shubham Vyas
- Department of Chemistry, Colorado School of Mines, Golden, Colorado 80401, United States
| |
Collapse
|
27
|
Li Y, Pan GH, Hu M, Liu B, Song RJ, Li JH. Intermolecular oxidative decarbonylative [2 + 2 + 2] carbocyclization of N-(2-ethynylaryl)acrylamides with tertiary and secondary alkyl aldehydes involving C(sp 3)-H functionalization. Chem Sci 2016; 7:7050-7054. [PMID: 28337339 PMCID: PMC5282743 DOI: 10.1039/c6sc02451c] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2016] [Accepted: 07/16/2016] [Indexed: 12/13/2022] Open
Abstract
A new metal-free oxidative decarbonylative [2 + 2 + 2] carbocyclization of N-(2-ethynylaryl)acrylamides with tertiary and secondary alkyl aldehydes is described. This reaction enables the formation of three new C-C bonds in a single reaction by a sequence of oxidative decarbonylation, radical addition across C-C unsaturated bonds, C-H functionalization and annulation, and represents the first oxidative decarbonylative [2 + 2 + 2] carbocyclization approach using tertiary and secondary alkyl aldehydes as a two carbon unit for assembling six-membered carbocycle-fused polycycles.
Collapse
Affiliation(s)
- Yang Li
- State Key Laboratory of Chemo/Biosensing and Chemometrics , Hunan University , Changsha 410082 , China . ; ; Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle , Nanchang Hangkong University , Nanchang 330063 , China
| | - Gao-Hui Pan
- State Key Laboratory of Chemo/Biosensing and Chemometrics , Hunan University , Changsha 410082 , China . ; ; Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle , Nanchang Hangkong University , Nanchang 330063 , China
| | - Ming Hu
- State Key Laboratory of Chemo/Biosensing and Chemometrics , Hunan University , Changsha 410082 , China . ; ; Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle , Nanchang Hangkong University , Nanchang 330063 , China
| | - Bang Liu
- State Key Laboratory of Chemo/Biosensing and Chemometrics , Hunan University , Changsha 410082 , China . ; ; Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle , Nanchang Hangkong University , Nanchang 330063 , China
| | - Ren-Jie Song
- State Key Laboratory of Chemo/Biosensing and Chemometrics , Hunan University , Changsha 410082 , China . ; ; Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle , Nanchang Hangkong University , Nanchang 330063 , China
| | - Jin-Heng Li
- State Key Laboratory of Chemo/Biosensing and Chemometrics , Hunan University , Changsha 410082 , China . ; ; Key Laboratory of Jiangxi Province for Persistent Pollutants Control and Resources Recycle , Nanchang Hangkong University , Nanchang 330063 , China ; State Key Laboratory of Applied Organic Chemistry , Lanzhou University , Lanzhou 730000 , China
| |
Collapse
|
28
|
Zhou CW, Simmie JM, Pitz WJ, Curran HJ. Toward the Development of a Fundamentally Based Chemical Model for Cyclopentanone: High-Pressure-Limit Rate Constants for H Atom Abstraction and Fuel Radical Decomposition. J Phys Chem A 2016; 120:7037-44. [PMID: 27558073 DOI: 10.1021/acs.jpca.6b03994] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Theoretical aspects of the development of a chemical kinetic model for the pyrolysis and combustion of a cyclic ketone, cyclopentanone, are considered. Calculated thermodynamic and kinetic data are presented for the first time for the principal species including 2- and 3-oxo-cyclopentyl radicals, which are in reasonable agreement with the literature. These radicals can be formed via H atom abstraction reactions by Ḣ and Ö atoms and ȮH, HȮ2, and ĊH3 radicals, the rate constants of which have been calculated. Abstraction from the β-hydrogen atom is the dominant process when ȮH is involved, but the reverse holds true for HȮ2 radicals. The subsequent β-scission of the radicals formed is also determined, and it is shown that recent tunable VUV photoionization mass spectrometry experiments can be interpreted in this light. The bulk of the calculations used the composite model chemistry G4, which was benchmarked in the simplest case with a coupled cluster treatment, CCSD(T), in the complete basis set limit.
Collapse
Affiliation(s)
- Chong-Wen Zhou
- School of Chemistry & Combustion Chemistry Centre, National University of Ireland Galway , Galway H91 TK33, Ireland
| | - John M Simmie
- School of Chemistry & Combustion Chemistry Centre, National University of Ireland Galway , Galway H91 TK33, Ireland
| | - William J Pitz
- Lawrence Livermore National Laboratory , Livermore, California 94550, United States
| | - Henry J Curran
- School of Chemistry & Combustion Chemistry Centre, National University of Ireland Galway , Galway H91 TK33, Ireland
| |
Collapse
|
29
|
Li Y, Liu B, Song RJ, Wang QA, Li JH. Visible Light-Initiated C(sp3)Br/C(sp3)H Functionalization of α-Carbonyl Alkyl Bromides through Hydride Radical Shift. Adv Synth Catal 2016. [DOI: 10.1002/adsc.201501134] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
|
30
|
Ratkiewicz A, Huynh LK, Truong TN. Performance of First-Principles-Based Reaction Class Transition State Theory. J Phys Chem B 2016; 120:1871-84. [PMID: 26752508 DOI: 10.1021/acs.jpcb.5b09564] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Performance of the Reaction Class Transition State Theory (RC-TST) for prediction of rates constants of elementary reactions is examined using data from its previous applications to a number of different reaction classes. The RC-TST theory is taking advantage of the common structure denominator of all reactions in a given family combined with structure activity relationships to provide a rigorous theoretical framework to obtain rate expression of any reaction within a reaction class in a simple and cost-effective manner. This opens the possibility for integrating this methodology with an automated mechanism generator for "on-the-fly" generation of accurate kinetic models of complex reacting systems.
Collapse
Affiliation(s)
- Artur Ratkiewicz
- Chemistry Institute, University of Bialystok , Ciolkowskiego 1K 15-245 Bialystok, Poland
| | - Lam K Huynh
- Institute for Computational Science and Technology at Ho Chi Minh City , Tan Chanh Hiep Ward, District 12, Ho Chi Minh City, Vietnam.,International University, VNU-HCMC , Thu Duc District, Ho Chi Minh City, Vietnam
| | - Thanh N Truong
- Henry Eyring Center for Theoretical Chemistry, Department of Chemistry, University of Utah , 315 South 1400 East, Room 2020, Salt Lake City, Utah 84112, United States
| |
Collapse
|
31
|
Mai TVT, Ratkiewicz A, Duong MV, Huynh LK. Direct ab initio study of the C6H6+ CH3/C2H5= C6H5+ CH4/C2H6 reactions. Chem Phys Lett 2016. [DOI: 10.1016/j.cplett.2015.12.063] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
32
|
Wang K, Villano SM, Dean AM. Ab initio study of the influence of resonance stabilization on intramolecular ring closure reactions of hydrocarbon radicals. Phys Chem Chem Phys 2016; 18:8437-52. [DOI: 10.1039/c5cp06994g] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The cyclization reactions of dieneyl radicals provide a low energy route to the formation of molecular weight growth products.
Collapse
Affiliation(s)
- Kun Wang
- Chemical and Biological Engineering Dept
- Colorado School of Mines
- Golden
- USA
| | | | - Anthony M. Dean
- Chemical and Biological Engineering Dept
- Colorado School of Mines
- Golden
- USA
| |
Collapse
|
33
|
Ning H, Gong C, Li Z, Li X. Pressure-Dependent Kinetics of Initial Reactions in Iso-octane Pyrolysis. J Phys Chem A 2015; 119:4093-107. [DOI: 10.1021/acs.jpca.5b02013] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- HongBo Ning
- College
of Chemical Engineering, Sichuan University, Chengdu 610065, People’s Republic of China
| | - ChunMing Gong
- College
of Chemical Engineering, Sichuan University, Chengdu 610065, People’s Republic of China
| | - ZeRong Li
- College
of Chemistry, Sichuan University, Chengdu 610064, People’s Republic of China
| | - XiangYuan Li
- College
of Chemical Engineering, Sichuan University, Chengdu 610065, People’s Republic of China
| |
Collapse
|
34
|
Le XT, Mai TVT, Ratkiewicz A, Huynh LK. Mechanism and Kinetics of Low-Temperature Oxidation of a Biodiesel Surrogate: Methyl Propanoate Radicals with Oxygen Molecule. J Phys Chem A 2015; 119:3689-703. [DOI: 10.1021/jp5128282] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Xuan T. Le
- Institute for Computational Science and Technology, Ho Chi Minh City, Vietnam
| | - Tam V. T. Mai
- Institute for Computational Science and Technology, Ho Chi Minh City, Vietnam
| | - Artur Ratkiewicz
- Institute
of Chemistry, University of Bialystok, ul Hurtowa 1, 15-399 Białystok, Poland
| | - Lam K. Huynh
- Institute for Computational Science and Technology, Ho Chi Minh City, Vietnam
- International University, Vietnam National University - HCMC, Linh Trung, Thu Duc District, Ho Chi Minh City, Vietnam
| |
Collapse
|
35
|
Wang K, Villano SM, Dean AM. Reactions of allylic radicals that impact molecular weight growth kinetics. Phys Chem Chem Phys 2015; 17:6255-73. [DOI: 10.1039/c4cp05308g] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The reactions of allylic radicals have the potential to play a critical role in molecular weight growth (MWG) kinetics during hydrocarbon oxidation and/or pyrolysis.
Collapse
Affiliation(s)
- Kun Wang
- Chemical and Biological Engineering Department
- Colorado School of Mines
- Golden
- USA
| | | | - Anthony M. Dean
- Chemical and Biological Engineering Department
- Colorado School of Mines
- Golden
- USA
| |
Collapse
|