1
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Nayak S, Rajakumar B. High-Temperature Pyrolysis Study of 2-Methyl-2-butanol behind Reflected Shock Wave: Shock Tube and Computational Study. J Phys Chem A 2024; 128:5691-5706. [PMID: 38973315 DOI: 10.1021/acs.jpca.4c01593] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/09/2024]
Abstract
Pyrolysis of a branched alcohol, 2-methyl-2-butanol (2M2BOH), was carried out behind the reflected shock wave in the temperature range of 1011-1303 K and under pressures varying from 9.3 to 14.6 atm. Qualitative and quantitative analysis of the postshock mixture was performed using gas chromatography-mass spectrometry and gas chromatography with a flame ionization detector, respectively. The rate coefficients for the C-C and C-O bond cleavage reaction pathways were calculated using the variational transition-state theory. The Rice-Ramsperger-Kessel-Marcus/Master equation was employed to calculate the rate coefficients for the H2O-elimination reactions, unimolecular dissociation, and isomerization reaction pathways. The overall decomposition rate coefficient for the 2-methyl 2-butanol (2M2BOH) was estimated to be k t o t a l e x p t ( 1011 - 1303 K ) = ( 3.29 ± 0.73 ) × 10 11 × exp [ - ( 47.41 ± 0.53 T ) ] s - 1 , where activation energy is given in kcal mol-1. The reaction path analysis was performed, which gives information regarding the contribution of individual intermediate species toward the decomposition of 2M2BOH. A set of reactions was proposed and used to simulate the combustion chemistry of 2M2BOH, which consists of 48 reactions and 39 species. The experimentally measured and simulated mole fractions for the reactant and products showed reasonably good agreement. This work additionally investigates the effect of branching on the decomposition kinetics of long-chain alcohols.
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Affiliation(s)
- Subhadarsi Nayak
- Department of Chemistry, Indian Institute of Technology Madras, Chennai 600036, India
| | - Balla Rajakumar
- Department of Chemistry, Indian Institute of Technology Madras, Chennai 600036, India
- Centre for Atmospheric and Climate Sciences, Indian Institute of Technology Madras, Chennai 600036, India
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2
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Welsh BA, Corrigan ME, Assaf E, Nauta K, Sebastianelli P, Jordan MJT, Fittschen C, Kable SH. Photophysical oxidation of HCHO produces HO 2 radicals. Nat Chem 2023; 15:1350-1357. [PMID: 37414879 DOI: 10.1038/s41557-023-01272-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2022] [Accepted: 06/07/2023] [Indexed: 07/08/2023]
Abstract
Formaldehyde, HCHO, is the highest-volume carbonyl in the atmosphere. It absorbs sunlight at wavelengths shorter than 330 nm and photolyses to form H and HCO radicals, which then react with O2 to form HO2. Here we show HCHO has an additional HO2 formation pathway. At photolysis energies below the energetic threshold for radical formation we directly detect HO2 at low pressures by cavity ring-down spectroscopy and indirectly detect HO2 at 1 bar by Fourier-transform infrared spectroscopy end-product analysis. Supported by electronic structure theory and master equation simulations, we attribute this HO2 to photophysical oxidation (PPO): photoexcited HCHO relaxes non-radiatively to the ground electronic state where the far-from-equilibrium, vibrationally activated HCHO molecules react with thermal O2. PPO is likely to be a general mechanism in tropospheric chemistry and, unlike photolysis, PPO will increase with increasing O2 pressure.
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Affiliation(s)
- Blair A Welsh
- School of Chemistry, University of New South Wales, Kensington, New South Wales, Australia
- Combustion Research Facility, Sandia National Laboratories, Livermore, CA, USA
| | - Maggie E Corrigan
- School of Chemistry, University of Sydney, Sydney, New South Wales, Australia
| | - Emmanuel Assaf
- Université Lille, CNRS, UMR 8522, PC2A-Physicochimie des Processus de Combustion et de l'Atmosphère, Lille, France
- Chemical Sciences Laboratory, National Oceanic and Atmospheric Administration, Boulder, CO, USA
- Cooperative Institute for Research in Environmental Sciences, University of Colorado, Boulder, CO, USA
| | - Klaas Nauta
- School of Chemistry, University of New South Wales, Kensington, New South Wales, Australia
| | - Paolo Sebastianelli
- School of Chemistry, University of New South Wales, Kensington, New South Wales, Australia
- School of Earth, Atmospheric and Life Sciences, University of Wollongong, Wollongong, New South Wales, Australia
| | - Meredith J T Jordan
- School of Chemistry, University of Sydney, Sydney, New South Wales, Australia.
| | - Christa Fittschen
- Université Lille, CNRS, UMR 8522, PC2A-Physicochimie des Processus de Combustion et de l'Atmosphère, Lille, France
| | - Scott H Kable
- School of Chemistry, University of New South Wales, Kensington, New South Wales, Australia.
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3
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Chen Y, Yan H, Liao Q, Zhang D, Lin S, Hao E, Murtaza R, Li C, Wu C, Duan C, Shi L. Synthesis of Homoallylic Amines by Radical Allylation of Imines with Butadiene under Photoredox Catalysis. Angew Chem Int Ed Engl 2022; 61:e202204516. [DOI: 10.1002/anie.202204516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2022] [Indexed: 11/06/2022]
Affiliation(s)
- Yuqing Chen
- State Key Laboratory of Fine Chemicals Zhang Dayu School of Chemistry Dalian University of Technology 116024 Dalian China
| | - Huaipu Yan
- State Key Laboratory of Fine Chemicals Zhang Dayu School of Chemistry Dalian University of Technology 116024 Dalian China
| | - Qian Liao
- State Key Laboratory of Fine Chemicals Zhang Dayu School of Chemistry Dalian University of Technology 116024 Dalian China
| | - Dandan Zhang
- State Key Laboratory of Fine Chemicals Zhang Dayu School of Chemistry Dalian University of Technology 116024 Dalian China
| | - Shuangjie Lin
- State Key Laboratory of Fine Chemicals Zhang Dayu School of Chemistry Dalian University of Technology 116024 Dalian China
| | - Erjun Hao
- School of Chemistry and Chemical Engineering Henan Normal University 453007 Xinxiang China
| | - Rukhsana Murtaza
- State Key Laboratory of Fine Chemicals Zhang Dayu School of Chemistry Dalian University of Technology 116024 Dalian China
| | - Chenchen Li
- Frontier Institute of Science and Technology Xi'an Jiaotong University 710054 Xi'an China
| | - Chao Wu
- Frontier Institute of Science and Technology Xi'an Jiaotong University 710054 Xi'an China
| | - Chunying Duan
- State Key Laboratory of Fine Chemicals Zhang Dayu School of Chemistry Dalian University of Technology 116024 Dalian China
| | - Lei Shi
- State Key Laboratory of Fine Chemicals Zhang Dayu School of Chemistry Dalian University of Technology 116024 Dalian China
- School of Chemistry and Chemical Engineering Henan Normal University 453007 Xinxiang China
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4
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Chen Y, Yan H, Liao Q, Zhang D, Lin S, Hao E, Murtaza R, Li C, Wu C, Duan C, Shi L. Synthesis of Homoallylic Amines by Radical Allylation of Imines with Butadiene under Photoredox Catalysis. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202204516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Yuqing Chen
- State Key Laboratory of Fine Chemicals Zhang Dayu School of Chemistry Dalian University of Technology 116024 Dalian China
| | - Huaipu Yan
- State Key Laboratory of Fine Chemicals Zhang Dayu School of Chemistry Dalian University of Technology 116024 Dalian China
| | - Qian Liao
- State Key Laboratory of Fine Chemicals Zhang Dayu School of Chemistry Dalian University of Technology 116024 Dalian China
| | - Dandan Zhang
- State Key Laboratory of Fine Chemicals Zhang Dayu School of Chemistry Dalian University of Technology 116024 Dalian China
| | - Shuangjie Lin
- State Key Laboratory of Fine Chemicals Zhang Dayu School of Chemistry Dalian University of Technology 116024 Dalian China
| | - Erjun Hao
- School of Chemistry and Chemical Engineering Henan Normal University 453007 Xinxiang China
| | - Rukhsana Murtaza
- State Key Laboratory of Fine Chemicals Zhang Dayu School of Chemistry Dalian University of Technology 116024 Dalian China
| | - Chenchen Li
- Frontier Institute of Science and Technology Xi'an Jiaotong University 710054 Xi'an China
| | - Chao Wu
- Frontier Institute of Science and Technology Xi'an Jiaotong University 710054 Xi'an China
| | - Chunying Duan
- State Key Laboratory of Fine Chemicals Zhang Dayu School of Chemistry Dalian University of Technology 116024 Dalian China
| | - Lei Shi
- State Key Laboratory of Fine Chemicals Zhang Dayu School of Chemistry Dalian University of Technology 116024 Dalian China
- School of Chemistry and Chemical Engineering Henan Normal University 453007 Xinxiang China
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5
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Jasper A. Predicting third-body collision efficiencies for water and other polyatomic baths. Faraday Discuss 2022; 238:68-86. [DOI: 10.1039/d2fd00038e] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Low-pressure-limit microcanonical (collisional activation) and thermal rate constants are predicted using a combination of automated ab initio potential energy surface construction, classical trajectories, transition state theory, and a detailed kinetic...
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6
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Foley CD, Xie C, Guo H, Suits A. Quantum resonances and roaming dynamics in formaldehyde photodissociation. Faraday Discuss 2022; 238:249-265. [DOI: 10.1039/d2fd00050d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The unimolecular dissociation of formaldehyde is studied via excitation to the à band at several excitation energies from just below the ground state radical dissociation threshold to 5000 cm-1 above...
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7
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Mishra D, Reino-González J, Obaid R, LaForge AC, Díaz-Tendero S, Martín F, Berrah N. Ultrafast molecular dynamics in ionized 1- and 2-propanol: from simple fragmentation to complex isomerization and roaming mechanisms. Phys Chem Chem Phys 2021; 24:433-443. [PMID: 34897321 DOI: 10.1039/d1cp04011a] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Upon photoexcitation, molecules can undergo numerous complex processes, such as isomerization and roaming, leading to changes in the molecular and electronic structure. Here, we report on the time-resolved ultrafast nuclear dynamics, initiated by laser ionization, in the two structural isomers, 1- and 2-propanol, using a combination of pump-probe spectroscopy and coincident Coulomb explosion imaging. Our measurements, paired with quantum chemistry calculations, identify the mechanisms for the observed two- and three-body dissociation channels for both isomers. In particular, the fragmentation channel of 2-propanol associated with the loss of CH3 shows possible evidence of methyl roaming. Moreover, the electronic structure of this roaming methyl fragment could be responsible for the enhanced ionization also observed for this channel. Finally, comparison with similar studies done on ethanol and acetonitrile helps establish a correlation between the length of the alkyl chain and the likelihood of hydrogen migration.
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Affiliation(s)
- Debadarshini Mishra
- Department of Physics, University of Connecticut, Storrs, Connecticut, 06269, USA.
| | - Juan Reino-González
- Departamento de Química, Universidad Autónoma de Madrid, Módulo 13, 28049 Madrid, EU, Spain
| | - Razib Obaid
- Department of Physics, University of Connecticut, Storrs, Connecticut, 06269, USA.
| | - Aaron C LaForge
- Department of Physics, University of Connecticut, Storrs, Connecticut, 06269, USA.
| | - Sergio Díaz-Tendero
- Departamento de Química, Universidad Autónoma de Madrid, Módulo 13, 28049 Madrid, EU, Spain.,Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, 28049 Madrid, EU, Spain.,Institute for Advanced Research in Chemical Sciences(IAdChem), Universidad Autónoma de Madrid, 28049 Madrid, EU, Spain
| | - Fernando Martín
- Departamento de Química, Universidad Autónoma de Madrid, Módulo 13, 28049 Madrid, EU, Spain.,Condensed Matter Physics Center (IFIMAC), Universidad Autónoma de Madrid, 28049 Madrid, EU, Spain.,Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA-Nano), Campus de Cantoblanco, 28049 Madrid, EU, Spain.,Donostia International Physics Center (DIPC), Paseo Manuel de Lardizabal 4, 20018 Donostia-San Sebastián, EU, Spain
| | - Nora Berrah
- Department of Physics, University of Connecticut, Storrs, Connecticut, 06269, USA.
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8
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Yang X, Shen X, Zhao P, Law CK. Statistical Analysis on Rate Parameters of the H 2-O 2 Reaction System. J Phys Chem A 2021; 125:10223-10234. [PMID: 34788032 DOI: 10.1021/acs.jpca.1c08250] [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
Quantitative rate determination of elementary reactions is a major task in the study of chemical kinetics. To ensure the fidelity of their determination, progressively tightened constraints need to be placed on their measurement, especially with the development of various notable experimental techniques. However, the evaluation of reaction rates and their uncertainties is frequently conducted with substantial subjectivity due to data source, thermodynamic conditions, sampling range, and sparsity. To reduce the extent of biased rate evaluation, we propose herein an approach of uncertainty-weighted statistical analysis, utilizing weighted average, and weighted least-square regression in statistical inference. Based on the backbone H2/O2 chemistry, rate data for each elementary reaction are collected from the time-history profile in shock tube experiments and high-level theoretical calculations, with their assigned weight inversely depending on uncertainty, which would overall avoid subjective assessments and provide more accurate rate evaluation. Aided by sensitivity analysis, the rates of a few key reactions are further constrained in the less investigated low- to intermediate-temperature conditions using high-fidelity flow reactor data. Good performance of the constructed mechanism is confirmed with validation against the target of the high-fidelity flow reactor data. This study demonstrates a systematic approach for reaction rate evaluation and uncertainty quantification.
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Affiliation(s)
- Xueliang Yang
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544, United States
| | - Xiaobo Shen
- School of Resources and Environmental Engineering, East China University of Science and Technology, Shanghai 200237, China
| | - Peng Zhao
- Department of Mechanical, Aerospace & Biomedical Engineering, UT Space Institute, University of Tennessee, Knoxville, Tennessee 37388, United States
| | - Chung K Law
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544, United States
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9
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Foley CD, Xie C, Guo H, Suits AG. Orbiting resonances in formaldehyde reveal coupling of roaming, radical, and molecular channels. Science 2021; 374:1122-1127. [PMID: 34822294 DOI: 10.1126/science.abk0634] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
[Figure: see text].
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Affiliation(s)
- Casey D Foley
- Department of Chemistry, University of Missouri, Columbia, MO 65211, USA
| | - Changjian Xie
- Institute of Modern Physics, Shaanxi Key Laboratory for Theoretical Physics Frontiers, Northwest University, Xian, Shaanxi 710127, China.,Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, NM 87131, USA
| | - Hua Guo
- Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, NM 87131, USA
| | - Arthur G Suits
- Department of Chemistry, University of Missouri, Columbia, MO 65211, USA
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10
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Pelevkin AV, Loukhovitski BI, Sharipov AS. Reaction of the N Atom with Electronically Excited O 2 Revisited: A Theoretical Study. J Phys Chem A 2021; 125:8294-8312. [PMID: 34494840 DOI: 10.1021/acs.jpca.1c05733] [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 of the reaction of N with electronically excited O2 (singlet a1Δg and b1Σg+ states), potentially relevant for NOx formation in nonthermal air plasma, is theoretically studied using the multireference second-order perturbation theory. The corresponding thermodynamically and kinetically favored reaction pathways together with possible intersystem crossings are identified. It has been revealed that the energy barrier for the N + O2(a1Δg) → NO + O reaction is approximately twice the barrier height for the counterpart process with O2(X3Σg-). The molecular oxygen in the b1Σg+ state, in turn, proved to be even less reactive to atomic nitrogen than O2(a1Δg). Appropriate thermal rate constants for specified reaction channels are calculated by the variational transition-state theory incorporating corrections for the tunneling effect, nonadiabatic transitions, and anharmonicity of vibrations for transition states and reactants. The corresponding three-parameter Arrhenius expressions for the broad temperature range (T = 300-4000 K) are reported. At last, post-transition-state molecular dynamics simulations indicate that the N + O2(a1Δg) reaction produces vibrationally much colder NO molecules than the N + O2(X3Σg-) process.
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Affiliation(s)
- Alexey V Pelevkin
- Central Institute of Aviation Motors, Aviamotornaya 2, Moscow 111116, Russia
| | - Boris I Loukhovitski
- Central Institute of Aviation Motors, Aviamotornaya 2, Moscow 111116, Russia.,Joint Institute for High Temperatures of the Russian Academy of Sciences, Izhorskaya 13 Bldg. 2, Moscow 125412, Russia
| | - Alexander S Sharipov
- Central Institute of Aviation Motors, Aviamotornaya 2, Moscow 111116, Russia.,Joint Institute for High Temperatures of the Russian Academy of Sciences, Izhorskaya 13 Bldg. 2, Moscow 125412, Russia
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11
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Rajakumar B, Arathala P, Muthiah B. Thermal Decomposition of 2-Methyltetrahydrofuran behind Reflected Shock Waves over the Temperature Range of 1179-1361 K. J Phys Chem A 2021; 125:5406-5422. [PMID: 34128665 DOI: 10.1021/acs.jpca.0c11490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The thermal unimolecular decomposition of 2-methyltetrahydrofuran (2-MTHF) was studied behind reflected shock waves in a single-pulse shock tube over the temperature range of 1179-1361 K and pressure range of 9-17 atm. Methane, ethylene, ethane, 1,3-butadiene, propylene, acetaldehyde, and acetylene were identified as products in the decomposition of 2-MTHF. A reaction scheme was proposed to explain the mechanism for the observed products. The experimentally determined rate coefficients were best fit to an Arrhenius expression for the overall decomposition and is represented as ktotalexp(1179-1361 K) = (3.23 ± 0.59) × 1011 s-1 exp(-51.3 ± 1.4 kcal mol-1/RT). Quantum chemistry methods were used to calculate the energetics and kinetics of various possible unimolecular dissociation pathways involved in the thermal decomposition of 2-MTHF. The initial decomposition of 2-MTHF occurs predominantly via ring-methyl (C-CH3) single bond fission, leading to the formation of tetrahydrofuran (C4H7O) radical, and methyl radical was found to be the major reaction compared to all the possible initial bond fission, ring opening, and molecular elimination channels. The temperature-dependent rate coefficients for the unimolecular dissociation of 2-MTHF were calculated using the RRKM (Rice-Ramsperger-Kassel-Marcus) theory in combination with the CCSD(T)/cc-pVTZ//B3LYP/cc-pVTZ level of electronic structure calculations over the temperature range of 800-1500 K. The computed high-pressure limiting rate coefficients for the initial decomposition of 2-MTHF through C-CH3 single bond fission channel were found to be ∼2 times higher in the temperatures between 800 and 900 K, and above this temperature, they agree well with the values reported in the literature.
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Affiliation(s)
- Balla Rajakumar
- Department of Chemistry, Indian Institute of Technology Madras, Chennai 600036, India
| | - Parandaman Arathala
- Department of Chemistry, Indian Institute of Technology Madras, Chennai 600036, India
| | - Balaganesh Muthiah
- Department of Chemistry, Indian Institute of Technology Madras, Chennai 600036, India
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12
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Foley CD, Cooper GA, Tu J, Harmata M, Suits AG. HDCO radical dissociation thresholds by velocity map imaging. Mol Phys 2021. [DOI: 10.1080/00268976.2020.1813344] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- C. D. Foley
- Department of Chemistry, University of Missouri, Columbia, MO, USA
| | - G. A. Cooper
- Department of Chemistry, University of Missouri, Columbia, MO, USA
| | - J. Tu
- Department of Chemistry, University of Missouri, Columbia, MO, USA
| | - M. Harmata
- Department of Chemistry, University of Missouri, Columbia, MO, USA
| | - A. G. Suits
- Department of Chemistry, University of Missouri, Columbia, MO, USA
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13
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Rousso AC, Jasper AW, Ju Y, Hansen N. Extreme Low-Temperature Combustion Chemistry: Ozone-Initiated Oxidation of Methyl Hexanoate. J Phys Chem A 2020; 124:9897-9914. [PMID: 33174431 DOI: 10.1021/acs.jpca.0c07584] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The accelerating chemical effect of ozone addition on the oxidation chemistry of methyl hexanoate [CH3(CH2)4C(═O)OCH3] was investigated over a temperature range from 460 to 940 K. Using an externally heated jet-stirred reactor at p = 700 Torr (residence time τ = 1.3 s, stoichiometry φ = 0.5, 80% argon dilution), we explored the relevant chemical pathways by employing molecular-beam mass spectrometry with electron and single-photon ionization to trace the temperature dependencies of key intermediates, including many hydroperoxides. In the absence of ozone, reactivity is observed in the so-called low-temperature chemistry (LTC) regime between 550 and 700 K, which is governed by hydroperoxides formed from sequential O2 addition and isomerization reactions. At temperatures above 700 K, we observed the negative temperature coefficient (NTC) regime, in which the reactivity decreases with increasing temperatures, until near 800 K, where the reactivity increases again. Upon addition of ozone (1000 ppm), the overall reactivity of the system is dramatically changed due to the time scale of ozone decomposition in comparison to fuel oxidation time scales of the mixtures at different temperatures. While the LTC regime seems to be only slightly affected by the addition of ozone with respect to the identity and quantity of the observed intermediates, we observed an increased reactivity in the intermediate NTC temperature range. Furthermore, we observed experimental evidence for an additional oxidation regime in the range near 500 K, herein referred to as the extreme low-temperature chemistry (ELTC) regime. Experimental evidence and theoretical rate constant calculations indicate that this ELTC regime is likely to be initiated by H abstraction from methyl hexanoate via O atoms, which originate from thermal O3 decomposition. The theoretical calculations show that the rate constants for methyl ester initiation via abstraction by O atoms increase dramatically with the size of the methyl ester, suggesting that ELTC is likely not important for the smaller methyl esters. Experimental evidence is provided indicating that, similar to the LTC regime, the chemistry in the ELTC regime is dominated by hydroperoxide chemistry. However, mass spectra recorded at various reactor temperatures and at different photon energies provide experimental evidence of some differences in chemical species between the ELTC and the LTC temperature ranges.
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Affiliation(s)
- Aric C Rousso
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544, United States
| | - Ahren W Jasper
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Yiguang Ju
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey 08544, United States
| | - Nils Hansen
- Combustion Research Facility, Sandia National Laboratories, Livermore, California 94551, United States
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14
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Quantum Chemical and Monte Carlo Simulation Studies on Inhibition Performance of Caffeine and Its Derivatives against Corrosion of Copper. COATINGS 2020. [DOI: 10.3390/coatings10111086] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Abstract
Performance tests on caffeine’s corrosion inhibition properties and their derivatives against copper corrosion have been previously reported experimentally using gravimetric and electrochemical analyses. The test was able to measure the efficiency of their corrosion inhibition accurately. However, the caffeine and its derivatives’ structure patterns and coating mechanisms when interacting with metals during copper corrosion inhibition have not been explained in detail by experimental studies. In the present study, the theoretical density functional study (DFT), ab initio MP2, and Monte Carlo simulation approaches explain the problem. The geometrical and quantum chemical parameters of inhibitors were compared under normal and protonated conditions in the gas and aqueous environments. Theoretical studies can accurately determine the molecule’s geometrical parameters and successfully explain the quantum parameters of inhibitors. Molecular dynamics are applied to study the mechanism of interaction between inhibitors and metal surfaces in an explicit water molecule environment. The energy absorption of caffeine and its derivatives on metal surfaces was linear, with quantum parameters calculated from the density functional theory and an ab initio approach. Furthermore, these theoretical study results align with the previously reported experimental studies published by de Souza et al. The inhibition efficiency ranking of studied molecules preventing copper corrosion was caffeine > theobromine > theophylline. This theoretical approach is expected to bridge the gap in designing effective corrosion inhibitors.
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15
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Maergoiz AI, Troe J, Ushakov V. Simplified Representation of Multichannel Thermal Unimolecular Reactions. II. Refined Parametrization of Formaldehyde Dissociation. Z PHYS CHEM 2020. [DOI: 10.1515/zpch-2019-1580] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Abstract
Simplified representations of branching fractions for thermal unimolecular two-channel reactions are discussed. The dissociation of formaldehyde serves as an illustrative example. Quantum-corrected classical trajectory calculations on an ab initio potential energy surface are combined with master equation calculations for collisional energy transfer. The treatment accounts for roaming atom dynamics. The dependence of the channel branching fractions on the bath gas pressure and temperature, on the collision efficiencies, and on the difference of channel threshold energies, are explored. It is discussed to what extent the derived simplified representations of channel branching fractions can be generalized.
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Affiliation(s)
- Anatoli I. Maergoiz
- Max-Planck-Institut für Biophysikalische Chemie , Am Fassberg 11 , D-37077 Göttingen , Germany
| | - Jürgen Troe
- Max-Planck-Institut für Biophysikalische Chemie , Am Fassberg 11 , D-37077 Göttingen , Germany
- Institut für Physikalische Chemie, Universität Göttingen , Tammannstrasse 6 , D-37077 Göttingen , Germany
| | - Vladimir Ushakov
- Institute of Problems of Chemical Physics , Russian Academy of Sciences , 142432 Chernogolovka , Russia
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16
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Abstract
Roaming reactions were first clearly identified in photodissociation of formaldehyde 15 years ago, and roaming dynamics are now recognized as a universal aspect of chemical reactivity. These reactions typically involve frustrated near-dissociation of a quasibound system to radical fragments, followed by reorientation at long range and intramolecular abstraction. The consequences can be unexpected formation of molecular products, depletion of the radical pool in chemical systems, and formation of products with unusual internal state distributions. In this review, I examine some current aspects of roaming reactions with an emphasis on experimental results, focusing on possible quantum effects in roaming and roaming dynamics in bimolecular systems. These considerations lead to a more inclusive definition of roaming reactions as those for which key dynamics take place at long range.
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Affiliation(s)
- Arthur G. Suits
- Department of Chemistry, University of Missouri, Columbia, Missouri 65211, USA
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17
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Levine DS, Hait D, Tubman NM, Lehtola S, Whaley KB, Head-Gordon M. CASSCF with Extremely Large Active Spaces Using the Adaptive Sampling Configuration Interaction Method. J Chem Theory Comput 2020; 16:2340-2354. [PMID: 32109055 DOI: 10.1021/acs.jctc.9b01255] [Citation(s) in RCA: 65] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
The complete active space self-consistent field (CASSCF) method is the principal approach employed for studying strongly correlated systems. However, exact CASSCF can only be performed on small active spaces of ∼20 electrons in ∼20 orbitals due to exponential growth in the computational cost. We show that employing the Adaptive Sampling Configuration Interaction (ASCI) method as an approximate Full CI solver in the active space allows CASSCF-like calculations within chemical accuracy (<1 kcal/mol for relative energies) in active spaces with more than ∼50 active electrons in ∼50 active orbitals, significantly increasing the sizes of systems amenable to accurate multiconfigurational treatment. The main challenge with using any selected CI-based approximate CASSCF is the orbital optimization problem; they tend to exhibit large numbers of local minima in orbital space due to their lack of invariance to active-active rotations (in addition to the local minima that exist in exact CASSCF). We highlight methods that can avoid spurious local extrema as a practical solution to the orbital optimization problem. We employ ASCI-SCF to demonstrate a lack of polyradical character in moderately sized periacenes with up to 52 correlated electrons and compare against heat-bath CI on an iron porphyrin system with more than 40 correlated electrons.
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Affiliation(s)
- Daniel S Levine
- Kenneth S. Pitzer Center for Theoretical Chemistry, Department of Chemistry, University of California, Berkeley, California 94720, United States.,Chemical Sciences Division, Lawrence Berkeley National Laboratory Berkeley, Berkeley, California 94720, United States
| | - Diptarka Hait
- Kenneth S. Pitzer Center for Theoretical Chemistry, Department of Chemistry, University of California, Berkeley, California 94720, United States.,Chemical Sciences Division, Lawrence Berkeley National Laboratory Berkeley, Berkeley, California 94720, United States
| | - Norm M Tubman
- Quantum Artificial Intelligence Lab (QuAIL), Exploration Technology Directorate, NASA Ames Research Center, Moffett Field, California 94035, United States
| | - Susi Lehtola
- Chemical Sciences Division, Lawrence Berkeley National Laboratory Berkeley, Berkeley, California 94720, United States
| | - K Birgitta Whaley
- Kenneth S. Pitzer Center for Theoretical Chemistry, Department of Chemistry, University of California, Berkeley, California 94720, United States.,Chemical Sciences Division, Lawrence Berkeley National Laboratory Berkeley, Berkeley, California 94720, United States
| | - Martin Head-Gordon
- Kenneth S. Pitzer Center for Theoretical Chemistry, Department of Chemistry, University of California, Berkeley, California 94720, United States.,Chemical Sciences Division, Lawrence Berkeley National Laboratory Berkeley, Berkeley, California 94720, United States
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18
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Wu CH, Magers DB, Harding LB, Klippenstein SJ, Allen WD. Reaction Profiles and Kinetics for Radical-Radical Hydrogen Abstraction via Multireference Coupled Cluster Theory. J Chem Theory Comput 2020; 16:1511-1525. [PMID: 32073856 DOI: 10.1021/acs.jctc.9b00966] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Radical-radical abstractions in hydrocarbon oxidation chemistry are disproportionation reactions that are generally exothermic with little or no barrier yet are underappreciated and poorly studied. Such challenging multireference electronic structure problems are tackled here using the recently developed state-specific multireference coupled cluster methods Mk-MRCCSD and Mk-MRCCSD(T), as well as the companion perturbation theory Mk-MRPT2 and the established MRCISD, MRCISD+Q, and CASPT2 approaches. Reaction paths are investigated for five prototypes involving radical-radical hydrogen abstraction: H + BeH → H2+ Be, H + NH2 → H2 + NH, CH3 + C2H5 → CH4 + C2H4, H + C2H5 → H2 + C2H4, and H + HCO → H2 + CO. Full configuration interaction (FCI) benchmark computations for the H + BeH, H + NH2, and H + HCO reactions prove that Mk-MRCCSD(T) provides superior accuracy for the interaction energies in the entrance channel, with mean absolute errors less than 0.3 kcal mol-1 and percentage deviations less than 10% over the fragment separations of relevance to kinetics. To facilitate combustion studies, energetics for the CH3 + C2H5, H + C2H5, and H + HCO reactions were computed at each level of theory with correlation-consistent basis sets (cc-pVXZ, X = T, Q, 5) and extrapolated to the complete basis set (CBS) limit. These CBS energies were coupled with CASPT2 projected vibrational frequencies along a minimum energy path to obtain rate constants for these three reactions. The rigorous Mk-MRCCSD(T)/CBS results demonstrate unequivocally that these three reactions proceed with no barrier in the entrance channel, contrary to some earlier predictions. Mk-MRCCSD(T) also reveals that the economical CASPT2 method performs well for large interfragment separations but may deteriorate substantially at shorter distances.
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Affiliation(s)
- Chia-Hua Wu
- Center for Computational Quantum Chemistry and Department of Chemistry, University of Georgia, Athens, Georgia 30602, United States
| | - D Brandon Magers
- Center for Computational Quantum Chemistry and Department of Chemistry, University of Georgia, Athens, Georgia 30602, United States.,Department of Chemistry and Physics, Belhaven University, Jackson, Mississippi 39202, United States
| | - Lawrence B Harding
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Stephen J Klippenstein
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Wesley D Allen
- Center for Computational Quantum Chemistry and Department of Chemistry, University of Georgia, Athens, Georgia 30602, United States
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19
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Jasper AW. Microcanonical Rate Constants for Unimolecular Reactions in the Low-Pressure Limit. J Phys Chem A 2020; 124:1205-1226. [DOI: 10.1021/acs.jpca.9b10693] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ahren W. Jasper
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
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20
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Li H, Suits AG. Universal crossed beam imaging studies of polyatomic reaction dynamics. Phys Chem Chem Phys 2020; 22:11126-11138. [DOI: 10.1039/d0cp00522c] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Crossed-beam imaging studies of polyatomic reactions show surprising dynamics not anticipated by extrapolation from smaller model systems.
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Affiliation(s)
- Hongwei Li
- Department of Chemistry
- University of Missouri
- Columbia
- USA
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21
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Villaverde JJ, Sevilla-Morán B, López-Goti C, Alonso-Prados JL, Sandín-España P. QSAR/QSPR models based on quantum chemistry for risk assessment of pesticides according to current European legislation. SAR AND QSAR IN ENVIRONMENTAL RESEARCH 2020; 31:49-72. [PMID: 31766890 DOI: 10.1080/1062936x.2019.1692368] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/08/2019] [Accepted: 11/10/2019] [Indexed: 06/10/2023]
Abstract
In Europe, agencies and official organizations involved in the pesticide control such as the EFSA, ECHA, JRC and ECETOC or even the OECD are pointing out that the software tools based on quantitative structure relationship models, i.e. QSAR and QSPR, have a huge potential to improve the pesticide risk assessment process. In this sense, these non-animal test methods can promote the competitiveness of agriculture in this region: the consumer safety is increased with them due to the possibility of perform an overall better risk assessment of the degradation products and metabolites from pesticides. However, the use of theses computational-based (in silico) tools must be much more systematised and harmonised, improving their validation and including case studies to test them. To open databases, incorporating critical data in an orderly manner for building the models, becomes also necessary. Moreover, quantum chemistry through the Density Functional Theory should be promoted as tool for calculation of quantum descriptors, especially for the study of similar compounds with the same carbon skeleton but differing substitution patterns, e.g. isomers.
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Affiliation(s)
| | | | - C López-Goti
- Unit of Plant Protection Products, INIA, Madrid, Spain
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22
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Döntgen M, Pekkanen TT, Joshi SP, Timonen RS, Eskola AJ. Oxidation Kinetics and Thermodynamics of Resonance-Stabilized Radicals: The Pent-1-en-3-yl + O 2 Reaction. J Phys Chem A 2019; 123:7897-7910. [PMID: 31446757 PMCID: PMC7076695 DOI: 10.1021/acs.jpca.9b03923] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2019] [Revised: 08/14/2019] [Indexed: 11/29/2022]
Abstract
The kinetics and thermochemistry of the pent-1-en-3-yl radical reaction with molecular oxygen (CH2CHCHCH2CH3 + O2) has been studied by both experimental and computational methods. The bimolecular rate coefficient of the reaction was measured as a function of temperature (198-370 K) and pressure (0.2-4.5 Torr) using laser photolysis-photoionization mass-spectrometry. Quantum chemical calculations were used to explore the potential energy surface of the reaction, after which Rice-Ramsperger-Kassel-Marcus theory/master equation simulations were performed to investigate the reaction. The experimental data were used to adjust key parameters, such as well depths, in the master equation model within methodological uncertainties. The master equation simulations suggest that the formation rates of the two potential RO2 adducts are equal and that the reaction to QOOH is slower than for saturated hydrocarbons. The initial addition reaction, CH2CHCHCH2CH3 + O2, is found to be barrierless when accounting for multireference effects. This is in agreement with the current experimental data, as well as with past experimental data for the allyl + O2 reaction. Finally, we conducted numerical simulations of the pent-1-en-3-yl + O2 reaction system and observed significant amounts of penta-1,3-diene being formed under engine-relevant conditions.
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Affiliation(s)
- Malte Döntgen
- Department
of Chemistry, University of Helsinki, P.O. Box 55 (A.I. Virtasen aukio 1), FI-00014, Helsinki, Finland
- School
of Engineering, Brown University, Providence, Rhode Island 02912, United States
| | - Timo T. Pekkanen
- Department
of Chemistry, University of Helsinki, P.O. Box 55 (A.I. Virtasen aukio 1), FI-00014, Helsinki, Finland
| | - Satya P. Joshi
- Department
of Chemistry, University of Helsinki, P.O. Box 55 (A.I. Virtasen aukio 1), FI-00014, Helsinki, Finland
| | - Raimo S. Timonen
- Department
of Chemistry, University of Helsinki, P.O. Box 55 (A.I. Virtasen aukio 1), FI-00014, Helsinki, Finland
| | - Arkke J. Eskola
- Department
of Chemistry, University of Helsinki, P.O. Box 55 (A.I. Virtasen aukio 1), FI-00014, Helsinki, Finland
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23
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Jasper AW, Harding LB, Knight C, Georgievskii Y. Anharmonic Rovibrational Partition Functions at High Temperatures: Tests of Reduced-Dimensional Models for Systems with up to Three Fluxional Modes. J Phys Chem A 2019; 123:6210-6228. [DOI: 10.1021/acs.jpca.9b03592] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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24
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Yoshida D, Takahashi K. Odd–Even Reactivity Variation Due to Dynamical Effects around the Roaming Saddle Points of the Reaction Between C n– Chain ( n = 2–8) and H 2. J Phys Chem A 2019; 123:5300-5308. [DOI: 10.1021/acs.jpca.9b03435] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Daisuke Yoshida
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, Taiwan 10617, Republic of China
| | - Kaito Takahashi
- Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei, Taiwan 10617, Republic of China
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25
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Macaluso V, Scuderi D, Crestoni ME, Fornarini S, Corinti D, Dalloz E, Martinez-Nunez E, Hase WL, Spezia R. l-Cysteine Modified by S-Sulfation: Consequence on Fragmentation Processes Elucidated by Tandem Mass Spectrometry and Chemical Dynamics Simulations. J Phys Chem A 2019; 123:3685-3696. [DOI: 10.1021/acs.jpca.9b01779] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Affiliation(s)
- Veronica Macaluso
- LAMBE, Univ Evry, CNRS, CEA, Université Paris-Saclay, 91025 Évry, France
| | - Debora Scuderi
- LCP, Laboratoire de Chimie Physique, Université Paris-Sud, Bat. 349, CNRS UMR8000, 15 rue Georges Clemenceau, 91405 Orsay Cedex, France
| | - Maria Elisa Crestoni
- Dipartimento di Chimica e Tecnologie del Farmaco, Università degli Studi di Roma La Sapienza, P.le A. Moro 5, 00185 Roma, Italy
| | - Simonetta Fornarini
- Dipartimento di Chimica e Tecnologie del Farmaco, Università degli Studi di Roma La Sapienza, P.le A. Moro 5, 00185 Roma, Italy
| | - Davide Corinti
- Dipartimento di Chimica e Tecnologie del Farmaco, Università degli Studi di Roma La Sapienza, P.le A. Moro 5, 00185 Roma, Italy
| | - Enzo Dalloz
- LCP, Laboratoire de Chimie Physique, Université Paris-Sud, Bat. 349, CNRS UMR8000, 15 rue Georges Clemenceau, 91405 Orsay Cedex, France
- Dipartimento di Chimica e Tecnologie del Farmaco, Università degli Studi di Roma La Sapienza, P.le A. Moro 5, 00185 Roma, Italy
| | - Emilio Martinez-Nunez
- Departamento de Química Física, Facultade de Química, Campus Vida, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain
| | - William L. Hase
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, Texas 79409, United States
| | - Riccardo Spezia
- LAMBE, Univ Evry, CNRS, CEA, Université Paris-Saclay, 91025 Évry, France
- CNRS, Laboratoire de Chimie Théorique, LCT, Sorbonne Université, 4, Place Jussieu, 75252 Paris Cedex 05, France
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26
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Foley CD, Alavi ST, Joalland B, Broderick BM, Dias N, Suits AG. Imaging the infrared multiphoton excitation and dissociation of propargyl chloride. Phys Chem Chem Phys 2019; 21:1528-1535. [PMID: 30617359 DOI: 10.1039/c8cp06668j] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Infrared multiphoton excitation is combined with UV excitation and state-resolved probes of Cl(2P3/2), Cl*(2P1/2), and HCl to study the photochemistry of propargyl chloride. The results show evidence both of infrared multiphoton dissociation on the ground electronic state and infrared multiphoton excitation followed by UV dissociation. The results are interpreted with the aid of a full characterization of the stationary points on the ground state using ab initio methods, as well as our recent experimental and theoretical characterization of the UV photochemistry of the molecule. The data suggest elimination of HCl on the ground electronic state produces linear propadienylidene as a coproduct over a roaming-like transition state that accesses the Cl-H-C abstraction geometry. This identification is supported by separate chirped-pulse microwave studies in a quasi-uniform flow also reported here.
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Affiliation(s)
- Casey D Foley
- Department of Chemistry, University of Missouri, Columbia, MO 65211, USA.
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27
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28
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Asatryan R, Pal Y, Hachmann J, Ruckenstein E. Roaming-like Mechanism for Dehydration of Diol Radicals. J Phys Chem A 2018; 122:9738-9754. [DOI: 10.1021/acs.jpca.8b08690] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Rubik Asatryan
- Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Buffalo, New York 14260, United States
| | - Yudhajit Pal
- Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Buffalo, New York 14260, United States
- Computational and Data-Enabled Science and Engineering Graduate Program, University at Buffalo, The State University of New York, Buffalo, New York 14260, United States
| | - Johannes Hachmann
- Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Buffalo, New York 14260, United States
- New York State Center of Excellence in Materials Informatics, Buffalo, New York 14203, United States
- Computational and Data-Enabled Science and Engineering Graduate Program, University at Buffalo, The State University of New York, Buffalo, New York 14260, United States
| | - Eli Ruckenstein
- Department of Chemical and Biological Engineering, University at Buffalo, The State University of New York, Buffalo, New York 14260, United States
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29
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Cofer-Shabica DV, Stratt RM. What is special about how roaming chemical reactions traverse their potential surfaces? Differences in geodesic paths between roaming and non-roaming events. J Chem Phys 2018; 146:214303. [PMID: 28595418 DOI: 10.1063/1.4984617] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
With the notable exception of some illustrative two-degree-of-freedom models whose surprising classical dynamics has been worked out in detail, theories of roaming have largely bypassed the issue of when and why the counterintuitive phenomenon of roaming occurs. We propose that a useful way to begin to address these issues is to look for the geodesic (most efficient) pathways through the potential surfaces of candidate systems. Although roaming manifests itself in an unusual behavior at asymptotic geometries, we found in the case of formaldehyde dissociation that it was the pathways traversing the parts of the potential surface corresponding to highly vibrationally excited reactants that were the most revealing. An examination of the geodesics for roaming pathways in this region finds that they are much less tightly defined than the geodesics in that same region that lead directly to dissociation (whether into closed-shell products or into radical products). Thus, the broader set of options available to the roaming channel gives it an entropic advantage over more conventional reaction channels. These observations suggest that what leads to roaming in other systems may be less the presence of a localized "roaming transition state," than the existence of an entire region of the potential surface conducive to multiple equivalent pathways.
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Affiliation(s)
| | - Richard M Stratt
- Department of Chemistry, Brown University, Providence, Rhode Island 02912, USA
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30
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Abstract
The phenomenon of roaming in chemical reactions has now become both commonly observed in experiment and extensively supported by theory and simulations. Roaming occurs in highly-excited molecules when the trajectories of atomic motion often bypass the minimum energy pathway and produce reaction in unexpected ways from unlikely geometries. The prototypical example is the unimolecular dissociation of formaldehyde (H2CO), in which the "normal" reaction proceeds through a tight transition state to yield H2 + CO but for which a high fraction of dissociations take place via a "roaming" mechanism in which one H atom moves far from the HCO, almost to dissociation, and then returns to abstract the second H atom. We review below the theories and simulations that have recently been developed to address and understand this new reaction phenomenon.
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Affiliation(s)
- Joel M Bowman
- Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University Atlanta, Georgia 30322, USA.
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31
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Chen WY, Matsui H, Wang NS. A comparative study on the production yield of H atom in the thermal decomposition of i-C4H10 and n-C4H10: Examination of the contribution of the roaming radical channels. Chem Phys Lett 2018. [DOI: 10.1016/j.cplett.2017.10.044] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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32
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Lizardo-Huerta JC, Sirjean B, Verdier L, Fournet R, Glaude PA. Thermal Decomposition of Phosgene and Diphosgene. J Phys Chem A 2017; 122:249-257. [PMID: 29215282 DOI: 10.1021/acs.jpca.7b09554] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Phosgene (COCl2) is a toxic compound used or formed in a wide range of applications. The understanding of its thermal decomposition for destruction processes or in the event of accidental fire of stored reserves is a major safety issue. In this study, a detailed chemical kinetic model for the thermal decomposition and combustion of phosgene and diphosgene is proposed for the first time. A large number of thermo-kinetic parameters were calculated using quantum chemistry and reaction rate theory. The model was validated against experimental pyrolysis data from the literature. It is predicted that the degradation of diphosgene is mainly ruled by a pericyclic reaction producing two molecules of phosgene and, to a lesser extent, by a roaming radical reaction yielding CO2 and CCl4. Phosgene is much more stable than diphosgene under high-temperature conditions, and its decomposition starts at higher temperatures. Decomposition products are CO and Cl2. An equimolar mixture of the latter molecules can be considered as a surrogate of phosgene from the kinetic point of view, but the important endothermic effect of the decomposition reaction can lead to different behaviors, for instance, in the case of autoignition under high pressure and high temperature.
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Affiliation(s)
- Juan-Carlos Lizardo-Huerta
- Laboratoire Réactions et Génie des Procédés, CNRS, Université de Lorraine , 1 rue Grandville BP 20451 54001 Nancy Cedex, France
| | - Baptiste Sirjean
- Laboratoire Réactions et Génie des Procédés, CNRS, Université de Lorraine , 1 rue Grandville BP 20451 54001 Nancy Cedex, France
| | - Laurent Verdier
- DGA Maîtrise NRBC, Site du Bouchet, 5 rue Lavoisier, BP n°3, 91710 Vert le Petit, France
| | - René Fournet
- Laboratoire Réactions et Génie des Procédés, CNRS, Université de Lorraine , 1 rue Grandville BP 20451 54001 Nancy Cedex, France
| | - Pierre-Alexandre Glaude
- Laboratoire Réactions et Génie des Procédés, CNRS, Université de Lorraine , 1 rue Grandville BP 20451 54001 Nancy Cedex, France
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33
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Cobos CJ, Hintzer K, Sölter L, Tellbach E, Thaler A, Troe J. Shock Wave and Theoretical Modeling Study of the Dissociation of CH 2F 2. I. Primary Processes. J Phys Chem A 2017; 121:7813-7819. [PMID: 28948790 DOI: 10.1021/acs.jpca.7b05854] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The unimolecular dissociation of CH2F2 leading to CF2 + H2, CHF + HF, or CHF2 + H is investigated by quantum-chemical calculations and unimolecular rate theory. Modeling of the rate constants is accompanied by shock wave experiments over the range of 1400-1800 K, monitoring the formation of CF2. It is shown that the energetically most favorable dissociation channel leading to CF2 + H2 has a higher threshold energy than the energetically less favorable one leading to CHF + HF. Falloff curves of the dissociations are modeled. Under the conditions of the described experiments, the primary dissociation CH2F2 → CHF + HF is followed by the reaction CHF + HF → CF2 + H2. The experimental value of the rate constant for the latter reaction indicates that it does not proceed by an addition-elimination process involving CH2F2* intermediates, as assumed before.
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Affiliation(s)
- C J Cobos
- INIFTA, Facultad de Ciencias Exactas, Universidad Nacional de La Plata, CONICET , Casilla de Correo 16, Sucursal 4, 1900 La Plata, Argentina
| | - K Hintzer
- Dyneon GmbH , Gendorf, D-84508 Burgkirchen, Germany
| | - L Sölter
- Institut für Physikalische Chemie, Universität Göttingen , Tammannstrasse 6, D-37077 Göttingen, Germany
| | - E Tellbach
- Institut für Physikalische Chemie, Universität Göttingen , Tammannstrasse 6, D-37077 Göttingen, Germany
| | - A Thaler
- Dyneon GmbH , Gendorf, D-84508 Burgkirchen, Germany
| | - J Troe
- Institut für Physikalische Chemie, Universität Göttingen , Tammannstrasse 6, D-37077 Göttingen, Germany.,Max-Planck-Institut für Biophysikalische Chemie , Am Fassberg 11, D-37077 Göttingen, Germany
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34
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Mauguière FA, Collins P, Kramer ZC, Carpenter BK, Ezra GS, Farantos SC, Wiggins S. Roaming: A Phase Space Perspective. Annu Rev Phys Chem 2017; 68:499-524. [DOI: 10.1146/annurev-physchem-052516-050613] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
| | - Peter Collins
- School of Mathematics, University of Bristol, Bristol BS8 1TW, United Kingdom;, ,
| | - Zeb C. Kramer
- Department of Chemistry and Biochemistry, La Salle University, Philadelphia, Pennsylvania 19141
| | - Barry K. Carpenter
- School of Chemistry, Cardiff University, Cardiff CF10 3AT, United Kingdom
| | - Gregory S. Ezra
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853
| | - Stavros C. Farantos
- Department of Chemistry, University of Crete, Heraklion 700 13, Greece
- Institute of Electronic Structure and Laser, Foundation for Research and Technology—Hellas, Heraklion 711 10, Greece
| | - Stephen Wiggins
- School of Mathematics, University of Bristol, Bristol BS8 1TW, United Kingdom;, ,
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35
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Wang X, Houston PL, Bowman JM. A new (multi-reference configuration interaction) potential energy surface for H 2CO and preliminary studies of roaming. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2017; 375:20160194. [PMID: 28320899 PMCID: PMC5360895 DOI: 10.1098/rsta.2016.0194] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 10/05/2016] [Indexed: 06/06/2023]
Abstract
We report a new global potential energy surface (PES) for H2CO, based on precise fitting of roughly 67 000 MRCI/cc-pVTZ energies. This PES describes the global minimum, the cis- and trans-HCOH isomers, and barriers relevant to isomerization, formation of the molecular (H2+CO) and radical (H+HCO) products, and the loose so-called roaming transition-state saddle point. The key features of the PES are reviewed and compared with a previous PES, denoted by PES04, based on five local fits that are 'stitched' together by switching functions (Zhang et al. 2004 J. Phys. Chem. A108, 8980-8986 (doi:10.1021/jp048339l)). Preliminary quasi-classical trajectory calculations are performed at the total energy of 36 233 cm-1 (103 kcal mol-1), relative to the H2CO global minimum, using the new PES, with a particular focus on roaming dynamics. When compared with the results from PES04, the new PES findings show similar rotational distributions, somewhat more roaming and substantially higher H2 vibrational excitation.This article is part of the themed issue 'Theoretical and computational studies of non-equilibrium and non-statistical dynamics in the gas phase, in the condensed phase and at interfaces'.
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Affiliation(s)
- Xiaohong Wang
- Department of Chemistry, and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, GA 30322, USA
| | - Paul L Houston
- School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA 30332, USA
- Department of Chemistry and Chemical Biology, Cornell University, Baker Laboratory, Ithaca, NY 14852, USA
| | - Joel M Bowman
- Department of Chemistry, and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, GA 30322, USA
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36
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Toulson BW, Kapnas KM, Fishman DA, Murray C. Competing pathways in the near-UV photochemistry of acetaldehyde. Phys Chem Chem Phys 2017; 19:14276-14288. [DOI: 10.1039/c7cp02573d] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Time-resolved ion imaging measurements have been performed to explore the photochemistry of acetaldehyde at photolysis wavelengths spanning the range 265–328 nm.
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Affiliation(s)
| | - Kara M. Kapnas
- Department of Chemistry
- University of California, Irvine
- Irvine
- USA
| | | | - Craig Murray
- Department of Chemistry
- University of California, Irvine
- Irvine
- USA
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37
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Viana RB. Tailoring the electronic properties among oxoarsine, arsinoyl and arsine oxide isomers: the simplest molecular systems with an arsenic–oxygen bond. RSC Adv 2016. [DOI: 10.1039/c6ra09517h] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The main goal of this investigation is to understand the reaction pathways and the electronic and spectroscopy properties of AsOHn radicals (n = 0–3), which are some of the simplest compound models with an arsenic–oxygen bond.
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Affiliation(s)
- Rommel B. Viana
- Departamento de Química e Física Molecular
- Instituto de Química de São Carlos
- Universidade de São Paulo
- São Carlos
- Brazil
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38
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Xing LL, Zhang XY, Wang ZD, Li S, Zhang LD. New Insight into Competition between Decomposition Pathways of Hydroperoxymethyl Formate in Low Temperature DME Oxidation. CHINESE J CHEM PHYS 2015. [DOI: 10.1063/1674-0068/28/cjcp1503053] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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39
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Añez R, Alejos P, Sierraalta A. HAl(OH)2 molecular structures and reaction paths. Post-Hartree–Fock, DFT calculations and infrared spectroscopic. COMPUT THEOR CHEM 2015. [DOI: 10.1016/j.comptc.2015.02.008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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40
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Abstract
Due to the prominent role of the propargyl radical for hydrocarbon growth within combustion environments, it is important to understand the kinetics of its formation and loss. The ab initio transition state theory-based master equation method is used to obtain theoretical kinetic predictions for the temperature and pressure dependence of the thermal decomposition of propargyl, which may be its primary loss channel under some conditions. The potential energy surface for the decomposition of propargyl is first mapped at a high level of theory with a combination of coupled cluster and multireference perturbation calculations. Variational transition state theory is then used to predict the microcanonical rate coefficients, which are subsequently implemented within the multiple-well multiple-channel master equation. A variety of energy transfer parameters are considered, and the sensitivity of the thermal rate predictions to these parameters is explored. The predictions for the thermal decomposition rate coefficient are found to be in good agreement with the limited experimental data. Modified Arrhenius representations of the rate constants are reported for utility in combustion modeling.
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Affiliation(s)
- Stephen J Klippenstein
- †Chemical Sciences and Engineering Division, Argonne National Laboratory, Argonne, Illinois 60439, United States
| | - James A Miller
- †Chemical Sciences and Engineering Division, Argonne National Laboratory, Argonne, Illinois 60439, United States
| | - Ahren W Jasper
- ‡Combustion Research Facility, Sandia National Laboratories, Livermore, California 94551, United States
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41
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Annesley CJ, Randazzo JB, Klippenstein SJ, Harding LB, Jasper AW, Georgievskii Y, Ruscic B, Tranter RS. Thermal Dissociation and Roaming Isomerization of Nitromethane: Experiment and Theory. J Phys Chem A 2015; 119:7872-93. [DOI: 10.1021/acs.jpca.5b01563] [Citation(s) in RCA: 51] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Christopher J. Annesley
- Chemical
Sciences and Engineering Division, Argonne National Laboratory, Argonne, Illinois 60439, United States
| | - John B. Randazzo
- Chemical
Sciences and Engineering Division, Argonne National Laboratory, Argonne, Illinois 60439, United States
| | - Stephen J. Klippenstein
- Chemical
Sciences and Engineering Division, Argonne National Laboratory, Argonne, Illinois 60439, United States
| | - Lawrence B. Harding
- Chemical
Sciences and Engineering Division, Argonne National Laboratory, Argonne, Illinois 60439, United States
| | - Ahren W. Jasper
- Combustion
Research Facility, Sandia National Laboratories, Livermore, California 94551-0969, United States
| | - Yuri Georgievskii
- Chemical
Sciences and Engineering Division, Argonne National Laboratory, Argonne, Illinois 60439, United States
| | - Branko Ruscic
- Chemical
Sciences and Engineering Division, Argonne National Laboratory, Argonne, Illinois 60439, United States
| | - Robert S. Tranter
- Chemical
Sciences and Engineering Division, Argonne National Laboratory, Argonne, Illinois 60439, United States
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42
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Mauguière FAL, Collins P, Ezra GS, Farantos SC, Wiggins S. Roaming dynamics in ion-molecule reactions: phase space reaction pathways and geometrical interpretation. J Chem Phys 2015; 140:134112. [PMID: 24712785 DOI: 10.1063/1.4870060] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
A model Hamiltonian for the reaction CH4(+) -> CH3(+) + H, parametrized to exhibit either early or late inner transition states, is employed to investigate the dynamical characteristics of the roaming mechanism. Tight/loose transition states and conventional/roaming reaction pathways are identified in terms of time-invariant objects in phase space. These are dividing surfaces associated with normally hyperbolic invariant manifolds (NHIMs). For systems with two degrees of freedom NHIMS are unstable periodic orbits which, in conjunction with their stable and unstable manifolds, unambiguously define the (locally) non-recrossing dividing surfaces assumed in statistical theories of reaction rates. By constructing periodic orbit continuation/bifurcation diagrams for two values of the potential function parameter corresponding to late and early transition states, respectively, and using the total energy as another parameter, we dynamically assign different regions of phase space to reactants and products as well as to conventional and roaming reaction pathways. The classical dynamics of the system are investigated by uniformly sampling trajectory initial conditions on the dividing surfaces. Trajectories are classified into four different categories: direct reactive and non-reactive trajectories, which lead to the formation of molecular and radical products respectively, and roaming reactive and non-reactive orbiting trajectories, which represent alternative pathways to form molecular and radical products. By analysing gap time distributions at several energies, we demonstrate that the phase space structure of the roaming region, which is strongly influenced by nonlinear resonances between the two degrees of freedom, results in nonexponential (nonstatistical) decay.
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Affiliation(s)
| | - Peter Collins
- School of Mathematics, University of Bristol, Bristol BS8 1TW, United Kingdom
| | - Gregory S Ezra
- Department of Chemistry and Chemical Biology, Baker Laboratory, Cornell University, Ithaca, New York 14853, USA
| | - Stavros C Farantos
- Institute of Electronic Structure and Laser, Foundation for Research and Technology - Hellas, and Department of Chemistry, University of Crete, Iraklion 711 10, Crete, Greece
| | - Stephen Wiggins
- School of Mathematics, University of Bristol, Bristol BS8 1TW, United Kingdom
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43
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Maeda S, Taketsugu T, Ohno K, Morokuma K. From Roaming Atoms to Hopping Surfaces: Mapping Out Global Reaction Routes in Photochemistry. J Am Chem Soc 2015; 137:3433-45. [DOI: 10.1021/ja512394y] [Citation(s) in RCA: 82] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Affiliation(s)
- Satoshi Maeda
- Department
of Chemistry, Faculty of Science, Hokkaido University, Sapporo 060-0810, Japan
| | - Tetsuya Taketsugu
- Department
of Chemistry, Faculty of Science, Hokkaido University, Sapporo 060-0810, Japan
| | - Koichi Ohno
- Graduate
School of Science, Tohoku University, Sendai 980-8578, Japan
- Institute for Quantum Chemical Exploration, Tokyo 108-0022, Japan
| | - Keiji Morokuma
- Fukui
Institute for Fundamental Chemistry, Kyoto University, Kyoto 606-8103, Japan
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44
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Raucci U, Savarese M, Adamo C, Ciofini I, Rega N. Intrinsic and Dynamical Reaction Pathways of an Excited State Proton Transfer. J Phys Chem B 2015; 119:2650-7. [DOI: 10.1021/jp508947f] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Umberto Raucci
- Dipartimento
di Scienze Chimiche, Universitá di Napoli ’Federico II’, Complesso Universitario di M.S.Angelo, via Cintia, I-80126 Napoli, Italy
| | - Marika Savarese
- Dipartimento
di Scienze Chimiche, Universitá di Napoli ’Federico II’, Complesso Universitario di M.S.Angelo, via Cintia, I-80126 Napoli, Italy
- IIT@CRIB
Center for Advanced Biomaterials for Healthcare, Italian Institute of Technology, Largo Barsanti e Matteucci, I-80125 Napoli, Italy
| | - Carlo Adamo
- Laboratoire
d’Electrochimie, Chimie des Interfaces et Modelisation pour
l’Energie, CNRS UMR-7575, Ecole Nationale Supérieure de Chimie de Paris, Chimie ParisTech, 11 rue P. et M. Curie, F-75231 Paris Cedex 05, France
- Institut Universitaire de France, 103 Bd Saint-Michel, F-75005 Paris, France
| | - Ilaria Ciofini
- Laboratoire
d’Electrochimie, Chimie des Interfaces et Modelisation pour
l’Energie, CNRS UMR-7575, Ecole Nationale Supérieure de Chimie de Paris, Chimie ParisTech, 11 rue P. et M. Curie, F-75231 Paris Cedex 05, France
| | - Nadia Rega
- Dipartimento
di Scienze Chimiche, Universitá di Napoli ’Federico II’, Complesso Universitario di M.S.Angelo, via Cintia, I-80126 Napoli, Italy
- IIT@CRIB
Center for Advanced Biomaterials for Healthcare, Italian Institute of Technology, Largo Barsanti e Matteucci, I-80125 Napoli, Italy
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45
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Tsai PY, Li HK, Kasai T, Lin KC. Roaming as the dominant mechanism for molecular products in the photodissociation of large aliphatic aldehydes. Phys Chem Chem Phys 2015; 17:23112-20. [DOI: 10.1039/c5cp03408f] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Photodissociation of isobutyraldehyde (C3H7CHO) at 248 nm is investigated using time-resolved Fourier-transform infrared emission spectroscopy to demonstrate the growing importance of the roaming pathway with increasing molecular size of aliphatic aldehydes.
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Affiliation(s)
- Po-Yu Tsai
- Department of Chemistry
- National Chung Hsing University
- Taichung 402
- Taiwan
| | - Hou-Kuan Li
- Department of Chemistry
- National Taiwan University
- and Institute of Atomic and Molecular Sciences
- Academia Sinica
- Taipei 106
| | - Toshio Kasai
- Department of Chemistry
- National Taiwan University
- and Institute of Atomic and Molecular Sciences
- Academia Sinica
- Taipei 106
| | - King-Chuen Lin
- Department of Chemistry
- National Taiwan University
- and Institute of Atomic and Molecular Sciences
- Academia Sinica
- Taipei 106
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46
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Tsai PY, Lin KC. Insight into the Photodissociation Dynamical Feature of Conventional Transition State and Roaming Pathways by an Impulsive Model. J Phys Chem A 2014; 119:29-38. [DOI: 10.1021/jp511000t] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Po-Yu Tsai
- Department
of Chemistry, National Taiwan University, and Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 106, Taiwan
| | - King-Chuen Lin
- Department
of Chemistry, National Taiwan University, and Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 106, Taiwan
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47
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Affiliation(s)
- Jürgen Troe
- Institut für Physikalische Chemie, Universität Göttingen , and Max-Planck-Institut für Biophysikalische Chemie, Göttingen, Germany
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48
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Affiliation(s)
- Joel M. Bowman
- Department of Chemistry, Emory University, Atlanta, GA, USA
- Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, GA, USA
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49
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Buras ZJ, Elsamra RMI, Jalan A, Middaugh JE, Green WH. Direct Kinetic Measurements of Reactions between the Simplest Criegee Intermediate CH2OO and Alkenes. J Phys Chem A 2014; 118:1997-2006. [DOI: 10.1021/jp4118985] [Citation(s) in RCA: 74] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Zachary J. Buras
- Department
of Chemical Engineering, Massachusetts Institute of Technology, 77 Massachusetts
Avenue, Cambridge, Massachusetts 02139, United States
| | - Rehab M. I. Elsamra
- Department
of Chemistry, Faculty of Science, Alexandria University, Ibrahimia, 21321, Alexandria, Egypt
| | - Amrit Jalan
- Department
of Chemical Engineering, Massachusetts Institute of Technology, 77 Massachusetts
Avenue, Cambridge, Massachusetts 02139, United States
| | - Joshua E. Middaugh
- Department
of Chemical Engineering, Massachusetts Institute of Technology, 77 Massachusetts
Avenue, Cambridge, Massachusetts 02139, United States
| | - William H. Green
- Department
of Chemical Engineering, Massachusetts Institute of Technology, 77 Massachusetts
Avenue, Cambridge, Massachusetts 02139, United States
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50
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Harabuchi Y, Maeda S, Taketsugu T, Ohno K. Direct Pathway for Water–Gas Shift Reaction in Gas Phase. CHEM LETT 2014. [DOI: 10.1246/cl.130940] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Yu Harabuchi
- Department of Chemistry, Faculty of Science, Hokkaido University
| | - Satoshi Maeda
- Department of Chemistry, Faculty of Science, Hokkaido University
| | | | - Koichi Ohno
- Department of Chemistry, Graduate School of Science, Tohoku University
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