1
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Li J, Li Y, Wu B, Xie M, Hu Y. Proton Transfer Processes in 2-Butenenitrile Dimer Cation Studied by Mass-Selective Infrared Spectroscopy. J Phys Chem A 2024; 128:4694-4700. [PMID: 38833155 DOI: 10.1021/acs.jpca.4c01989] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2024]
Abstract
2-Butenenitrile (2-Bu) is a recently discovered crucial interstellar molecule. Herein, an abnormal NH band was observed in the infrared spectrum of the 2-Bu dimer cation, suggestive of a proton transfer reaction within the cluster. Through a comprehensive theoretical analysis of the IR spectrum of (2-Bu)2+, we discovered not only the formation of a new C-N bond through the attachment of one 2-Bu to another but also the occurrence of a proton transfer reaction in the cluster. This proton was identified as originating from the methyl group of the attaching 2-Bu in the cluster based on the analysis of IR spectra of (2-Bu)+ and [2-Bu-acrylonitrile (AN)]+. Furthermore, the detailed reaction process of this ion-molecule reaction is examined with theoretical calculation. This finding contributes significantly to our deeper understanding of ion-molecule reactions in the gas phase and the formation of nitrogen-containing prebiotic molecules in the interstellar medium.
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Affiliation(s)
- Jingyu Li
- MOE Key Laboratory of Laser Life Science & Guangdong Provincial Key Laboratory of Laser Life Science, Guangzhou Key Laboratory of Spectral Analysis and Functional Probes, College of Biophotonics, South China Normal University, Guangzhou 510631, China
| | - Yujian Li
- MOE Key Laboratory of Laser Life Science & Guangdong Provincial Key Laboratory of Laser Life Science, Guangzhou Key Laboratory of Spectral Analysis and Functional Probes, College of Biophotonics, South China Normal University, Guangzhou 510631, China
| | - Bingbing Wu
- MOE Key Laboratory of Laser Life Science & Guangdong Provincial Key Laboratory of Laser Life Science, Guangzhou Key Laboratory of Spectral Analysis and Functional Probes, College of Biophotonics, South China Normal University, Guangzhou 510631, China
| | - Min Xie
- MOE Key Laboratory of Laser Life Science & Guangdong Provincial Key Laboratory of Laser Life Science, Guangzhou Key Laboratory of Spectral Analysis and Functional Probes, College of Biophotonics, South China Normal University, Guangzhou 510631, China
| | - Yongjun Hu
- MOE Key Laboratory of Laser Life Science & Guangdong Provincial Key Laboratory of Laser Life Science, Guangzhou Key Laboratory of Spectral Analysis and Functional Probes, College of Biophotonics, South China Normal University, Guangzhou 510631, China
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2
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Guillaume T, Hays BM, Gupta D, Cooke IR, Abdelkader Khedaoui O, Hearne TS, Drissi M, Sims IR. Product-specific reaction kinetics in continuous uniform supersonic flows probed by chirped-pulse microwave spectroscopy. J Chem Phys 2024; 160:204201. [PMID: 38808747 DOI: 10.1063/5.0203428] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2024] [Accepted: 05/06/2024] [Indexed: 05/30/2024] Open
Abstract
Experimental studies of the products of elementary gas-phase chemical reactions occurring at low temperatures (<50 K) are very scarce, but of importance for fundamental studies of reaction dynamics, comparisons with high-level quantum dynamical calculations, and, in particular, for providing data for the modeling of cold astrophysical environments, such as dense interstellar clouds, the atmospheres of the outer planets, and cometary comae. This study describes the construction and testing of a new apparatus designed to measure product branching fractions of elementary bimolecular gas-phase reactions at low temperatures. It combines chirped-pulse Fourier transform millimeter wave spectroscopy with continuous uniform supersonic flows and high repetition rate laser photolysis. After a comprehensive description of the apparatus, the experimental procedures and data processing protocols used for signal recovery, the capabilities of the instrument are explored by the study of the photodissociation of acrylonitrile and the detection of two of its photoproducts, HC3N and HCN. A description is then given of a study of the reactions of the CN radical with C2H2 at 30 K, detecting the HC3N product, and with C2H6 at 10 K, detecting the HCN product. A calibration of these two products is finally attempted using the photodissociation of acrylonitrile as a reference process. The limitations and possible improvements in the instrument are discussed in conclusion.
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Affiliation(s)
| | | | | | | | | | | | | | - Ian R Sims
- Univ Rennes, CNRS, IPR (Institut de Physique de Rennes) - UMR 6251, F-35000 Rennes, France
- Institut universitaire de France (IUF), France
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3
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Nixon CA. The Composition and Chemistry of Titan's Atmosphere. ACS EARTH & SPACE CHEMISTRY 2024; 8:406-456. [PMID: 38533193 PMCID: PMC10961852 DOI: 10.1021/acsearthspacechem.2c00041] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 11/02/2023] [Accepted: 02/02/2024] [Indexed: 03/28/2024]
Abstract
In this review I summarize the current state of knowledge about the composition of Titan's atmosphere and our current understanding of the suggested chemistry that leads to that observed composition. I begin with our present knowledge of the atmospheric composition, garnered from a variety of measurements including Cassini-Huygens, the Atacama Large Millimeter/submillimeter Array, and other ground- and space-based telescopes. This review focuses on the typical vertical profiles of gases at low latitudes rather than global and temporal variations. The main body of the review presents a chemical description of how complex molecules are believed to arise from simpler species, considering all known "stable" molecules-those that have been uniquely identified in the neutral atmosphere. The last section of the review is devoted to the gaps in our present knowledge of Titan's chemical composition and how further work may fill those gaps.
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Affiliation(s)
- Conor A. Nixon
- Planetary Systems Laboratory, NASA Goddard Space Flight Center, 8800 Greenbelt Road, Greenbelt, Maryland 20771, United
States
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4
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Ballotta B, Martínez-Núñez E, Rampino S, Barone V. New prebiotic molecules in the interstellar medium from the reaction between vinyl alcohol and CN radicals: unsupervised reaction mechanism discovery, accurate electronic structure calculations and kinetic simulations. Phys Chem Chem Phys 2023; 25:22840-22850. [PMID: 37584420 DOI: 10.1039/d3cp02571c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/17/2023]
Abstract
Vinyl alcohol (VyA) and cyanide (CN) radicals are relatively abundant in the interstellar medium (ISM). VyA is the enolic tautomer of acetaldehyde and has two low-lying conformers, characterized by the syn or anti placement of hydroxyl hydrogen with respect to the double bond. In this paper, we present a gas-phase model of the barrierless reactions of both VyA's conformers with CN employing accurate quantum chemical computations in the framework of a master equation approach based on the transition state theory. Our results indicate that both VyA conformers feature a similar reactivity with CN, starting with a barrierless addition to the double bond and followed by different isomerization, dissociation, and/or hydrogen elimination steps. The rate constants computed for temperatures up to 600 K show that several reaction channels are open even under the harsh conditions of the ISM, with the favoured one providing the first feasible formation route of a prebiotic molecule not yet detected in the ISM, namely cyanoacetaldehyde. This finding suggests looking for cyanoacetaldehyde in regions where both VyA and CN have already been detected, like, e.g., Sagittarius B2N or G+0.693-0.027.
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Affiliation(s)
- Bernardo Ballotta
- Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126, Pisa, Italy.
| | - Emilio Martínez-Núñez
- Departamento de Química Física, Facultade de Química, Campus Vida, Universidade de Santiago de Compostela, Avenida das Ciencias s/n, 15782, Santiago de Compostela, Spain
| | - Sergio Rampino
- Università degli Studi di Padova, Dipartimento di Scienze Chimiche, Via Marzolo 1, 35131 Padova, Italy
| | - Vincenzo Barone
- Scuola Normale Superiore, Piazza dei Cavalieri 7, 56126, Pisa, Italy.
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5
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Marchione D, Mancini L, Liang P, Vanuzzo G, Pirani F, Skouteris D, Rosi M, Casavecchia P, Balucani N. Unsaturated Dinitriles Formation Routes in Extraterrestrial Environments: A Combined Experimental and Theoretical Investigation of the Reaction between Cyano Radicals and Cyanoethene (C 2H 3CN). J Phys Chem A 2022; 126:3569-3582. [PMID: 35640168 PMCID: PMC9189926 DOI: 10.1021/acs.jpca.2c01802] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
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The reaction between
cyano radicals (CN, X2Σ+) and cyanoethene
(C2H3CN) has been
investigated by a combined approach coupling crossed molecular beam
(CMB) experiments with mass spectrometric detection and time-of-flight
analysis at a collision energy of 44.6 kJ mol–1 and
electronic structure calculations to determine the relevant potential
energy surface. The experimental results can be interpreted by assuming
the occurrence of a dominant reaction pathway leading to the two but-2-enedinitrile
(1,2-dicyanothene) isomers (E- and Z-NC–CH=CH–CN) in a H-displacement channel and,
to a much minor extent, to 1,1-dicyanoethene, CH2C(CN)2. In order to derive the product branching ratios under the
conditions of the CMB experiments and at colder temperatures, including
those relevant to Titan and to cold interstellar clouds, we have carried
out RRKM statistical calculations using the relevant potential energy
surface of the investigated reaction. We have also estimated the rate
coefficient at very low temperatures by employing a semiempirical
method for the treatment of long-range interactions. The reaction
has been found to be barrierless and fast also under the low temperature
conditions of cold interstellar clouds and the atmosphere of Titan.
Astrophysical implications and comparison with literature data are
also presented. On the basis of the present work, 1,2-dicyanothene
and 1,1-dicyanothene are excellent candidates for the search of dinitriles
in the interstellar medium.
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Affiliation(s)
- Demian Marchione
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, 06123 Perugia, Italy
| | - Luca Mancini
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, 06123 Perugia, Italy
| | - Pengxiao Liang
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, 06123 Perugia, Italy
| | - Gianmarco Vanuzzo
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, 06123 Perugia, Italy
| | - Fernando Pirani
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, 06123 Perugia, Italy
| | | | - Marzio Rosi
- Dipartimento di Ingegneria Civile ed Ambientale, Università degli Studi di Perugia, 06125 Perugia, Italy
| | - Piergiorgio Casavecchia
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, 06123 Perugia, Italy
| | - Nadia Balucani
- Dipartimento di Chimica, Biologia e Biotecnologie, Università degli Studi di Perugia, 06123 Perugia, Italy
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6
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Hickson KM, Loison JC, Larregaray P, Bonnet L, Wakelam V. An Experimental and Theoretical Investigation of the Gas-Phase C( 3P) + N 2O Reaction. Low Temperature Rate Constants and Astrochemical Implications. J Phys Chem A 2022; 126:940-950. [PMID: 35113561 DOI: 10.1021/acs.jpca.1c10112] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The reaction between atomic carbon in its ground electronic state, C(3P), and nitrous oxide, N2O, has been studied below room temperature due to its potential importance for astrochemistry, with both species considered to be present at high abundance levels in a range of interstellar environments. On the experimental side, we measured rate constants for this reaction over the 50-296 K range using a continuous supersonic flow reactor. C(3P) atoms were generated by the pulsed photolysis of carbon tetrabromide at 266 nm and were detected by pulsed laser-induced fluorescence at 115.8 nm. Additional measurements allowing the major product channels to be elucidated were also performed. On the theoretical side, statistical rate theory was used to calculate low temperature rate constants. These calculations employed the results of new electronic structure calculations of the 3A″ potential energy surface of CNNO and provided a basis to extrapolate the measured rate constants to lower temperatures and pressures. The rate constant was found to increase monotonically as the temperature falls (kC(3P)+N2O (296 K) = (3.4 ± 0.3) × 10-11 cm3 s-1), reaching a value of kC(3P)+N2O (50 K) = (7.9 ± 0.8) × 10-11 cm3 s-1 at 50 K. As current astrochemical models do not include the C + N2O reaction, we tested the influence of this process on interstellar N2O and other related species using a gas-grain model of dense interstellar clouds. These simulations predict that N2O abundances decrease significantly at intermediate times (103 - 105 years) when gas-phase C(3P) abundances are high.
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Affiliation(s)
- Kevin M Hickson
- Université Bordeaux, CNRS, Bordeaux INP, ISM, UMR 5255, F-33400 Talence, France
| | | | - Pascal Larregaray
- Université Bordeaux, CNRS, Bordeaux INP, ISM, UMR 5255, F-33400 Talence, France
| | - Laurent Bonnet
- Université Bordeaux, CNRS, Bordeaux INP, ISM, UMR 5255, F-33400 Talence, France
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7
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Blitz MA, Pilling MJ, Robertson SH, Seakins PW, Speak TH. Global Master Equation Analysis of Rate Data for the Reaction C 2H 4 + H ⇄ C 2H 5: Δ fH0⊖C 2H 5. J Phys Chem A 2021; 125:9548-9565. [PMID: 34704447 DOI: 10.1021/acs.jpca.1c05911] [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
While forward and reverse rate constants are frequently used to determine enthalpies of reaction and formation, this process is more difficult for pressure-dependent association/dissociation reactions, especially since the forward and reverse reactions are usually studied at very different temperatures. The problems can be overcome by using a data-fitting procedure based on a master equation model. This approach has been applied to existing experimental pressure-dependent forward and reverse rate coefficients for the reaction C2H4 + H ⇄ C2H5 (k1, k-1) using the MESMER code to determine ΔfH0⊖C2H5 from the enthalpy of the reaction. New measurements of k1, k-1 were included in analysis. They are based on laser flash photolysis with direct observation of H atom time profiles by vacuum ultraviolet laser-induced fluorescence under conditions where the approach to equilibrium could be observed. Measurements were made over the temperature range 798-828 K and with [He] from 2.33 to 7.21 × 1018 molecule cm-3. These data were then combined with a wide range of existing experimental data with helium as the bath gas (112 measurements of k1 and k-1, covering the temperature range 285-1094 K, and [He] = 7.1 × 1015-1.9 × 1019 molecule cm-3) and fitted using the master equation solver MESMER. The required vibrational frequencies and rotational constants of the system were obtained from ab initio calculations, and the activation threshold for association (ΔEthresh), enthalpy of reaction (ΔrH0⊖), imaginary frequency (υimag), and helium energy-transfer parameters (⟨ΔE⟩d,298(T/298)n) were optimized. The resulting parameters (errors are 2σ) are ΔEthresh = 11.43 ± 0.34 kJ mol-1, ΔrH0⊖ = -145.34 ± 0.60 kJ mol-1, υimag = 730 ± 130 cm-1, ⟨ΔE⟩d,298 = 54.2 ± 7.6 cm-1, and n = 1.17 ± 0.12. A value of ΔfH298.15⊖(C2H5) = 120.49 ± 0.57 kJ mol-1 is obtained by combining ΔrH0⊖ with standard enthalpies of formation for H and C2H4 and making the appropriate temperature corrections. The dependence of these parameters on how the internal rotor and CH2 inversion modes are treated has been explored. The experimental data for other bath gases have been analyzed, and data sets compatible with the potential energy surface parameters determined above have been identified. The parameters are virtually identical but with slightly smaller error limits. Parameterization of k1, k-1 using the Troe formalization has been used to investigate competition between ethyl decomposition and reaction with oxygen under combustion conditions.
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Affiliation(s)
- Mark A Blitz
- School of Chemistry, University of Leeds, Leeds LS2 9JT, U.K.,National Centre for Atmospheric Science (NCAS), University of Leeds, Leeds LS2 9JT, U.K
| | | | | | - Paul W Seakins
- School of Chemistry, University of Leeds, Leeds LS2 9JT, U.K
| | - Thomas H Speak
- School of Chemistry, University of Leeds, Leeds LS2 9JT, U.K
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8
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Huang J, Huang C, Wu X, Hou Q, Tian G, Yang J, Zhang F. Combined experimental and theoretical study on photoionization cross sections of benzonitrile and o/m/p-cyanotoluene. J Chem Phys 2021; 154:244301. [PMID: 34241365 DOI: 10.1063/5.0053119] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Photoionization cross sections (PICSs) for the products of the reaction from CN with toluene, including benzonitrile and o/m/p-cyanotoluene, were obtained at photon energies ranging from ionization thresholds to 14 eV by tunable synchrotron vacuum ultraviolet photoionization mass spectrometry (SVUV-PIMS). Theoretical calculations based on the frozen-core Hartree-Fock approximation and Franck-Condon simulations were carried out to cross-verify the measured PICS. The results show that the photoionization cross sections of benzonitrile and cyanotoluene isomers are similar. The generalized charge decomposition analysis was used to investigate the components of the highest occupied molecular orbital (HOMO) and HOMO-1. It was found that the HOMO and HOMO-1 of benzonitrile and cyanotoluene isomers are dominated by the features of the benzene ring, indicating that the substitution of CN and methyl has a minor influence on the PICS of the studied molecules. The reported PICS on benzonitrile and cyanotoluene isomers in the present work could contribute to the near-threshold PIMS experiments and determine the ionization and dissociation rates in interstellar space for these crucial species. The theoretical analysis on characteristics of molecular orbitals provides clues to estimating the PICS of similar substituted aromatic compounds.
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Affiliation(s)
- Jiabin Huang
- Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Can Huang
- Chair of Technical Thermodynamics, RWTH Aachen University, 52062 Aachen, Germany
| | - Xiaoqing Wu
- Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Qifeng Hou
- Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
| | - Guangjun Tian
- Key Laboratory for Microstructural Material Physics of Hebei Province, School of Science, Yanshan University, Qinhuangdao 066004, People's Republic of China
| | - Jiuzhong Yang
- National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei, Anhui 230029, People's Republic of China
| | - Feng Zhang
- Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026, People's Republic of China
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9
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Hickson KM, Bray C, Loison JC, Dobrijevic M. A kinetic study of the N( 2D) + C 2H 4 reaction at low temperature. Phys Chem Chem Phys 2020; 22:14026-14035. [PMID: 32558865 DOI: 10.1039/d0cp02083d] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Electronically excited nitrogen atoms N(2D) are important species in the photochemistry of N2 based planetary atmospheres such as Titan. Despite this, few N(2D) reactions have been studied over the appropriate low temperature range. During the present work, rate constants were measured for the N(2D) + ethene (C2H4) reaction using a supersonic flow reactor at temperatures between 50 K and 296 K. Here, a chemical reaction was used to generate N(2D) atoms, which were detected directly by laser induced fluorescence in the vacuum ultraviolet wavelength region. The measured rate constants displayed very little variation as a function of temperature, with substantially larger values than those obtained in previous work. Indeed, considering an average temperature of 170 K for the atmosphere of Titan leads to a rate constant that is almost seven times larger than the currently recommended value. In parallel, electronic structure calculations were performed to provide insight into the reactive process. While earlier theoretical work at a lower level predicted the presence of a barrier for the N(2D) + C2H4 reaction, the present calculations demonstrate that two of the five doublet potential energy surfaces correlating with reagents are likely to be attractive, presenting no barriers for the perpendicular approach of the N atom to the C[double bond, length as m-dash]C bond of ethene. The measured rate constants and new product channels taken from recent dynamical investigations of this process are included in a 1D coupled ion-neutral model of Titan's atmosphere. These simulations indicate that the modeled abundances of numerous nitrogen bearing compounds are noticeably affected by these changes.
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Affiliation(s)
- Kevin M Hickson
- Université de Bordeaux, Institut des Sciences Moléculaires, UMR 5255, F-33400 Talence, France.
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10
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Suas-David N, Thawoos S, Suits AG. A uniform flow-cavity ring-down spectrometer (UF-CRDS): A new setup for spectroscopy and kinetics at low temperature. J Chem Phys 2019; 151:244202. [PMID: 31893907 DOI: 10.1063/1.5125574] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The UF-CRDS (Uniform Flow-Cavity Ring Down Spectrometer) is a new setup coupling for the first time a pulsed uniform (Laval) flow with a continuous wave CRDS in the near infrared for spectroscopy and kinetics at low temperature. This high resolution and sensitive absorption spectrometer opens a new window into the phenomena occurring within UFs. The approach extends the detection range to new electronic and rovibrational transitions within Laval flows and offers the possibility to probe numerous species which have not been investigated yet. This new tool has been designed to probe radicals and reaction intermediates but also to follow the chemistry of hydrocarbon chains and PAHs which play a crucial role in the evolution of astrophysical environments. For kinetics measurements, the UF-CRDS combines the CRESU technique (French acronym meaning reaction kinetics in uniform supersonic flows) with the SKaR (Simultaneous Kinetics and Ring-Down) approach where, as indicated by its name, the entire reaction is monitored during each intensity decay within the high finesse cavity. The setup and the approach are demonstrated with the study of the reaction between CN (v = 1) and propene at low temperature. The recorded data are finally consistent with a previous study of the same reaction for CN (v = 0) relying on the CRESU technique with laser induced fluorescence detection.
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Affiliation(s)
- N Suas-David
- Department of Chemistry, University of Missouri, Columbia, Missouri 65211, USA
| | - S Thawoos
- Department of Chemistry, University of Missouri, Columbia, Missouri 65211, USA
| | - A G Suits
- Department of Chemistry, University of Missouri, Columbia, Missouri 65211, USA
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11
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12
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Trevitt AJ, Goulay F. Insights into gas-phase reaction mechanisms of small carbon radicals using isomer-resolved product detection. Phys Chem Chem Phys 2016; 18:5867-82. [DOI: 10.1039/c5cp06389b] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Gas-phase radical reactions of CN and CH with small hydrocarbons are overviewed with emphasis on isomer-resolved product detection.
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Affiliation(s)
- Adam J. Trevitt
- School of Chemistry
- University of Wollongong
- Wollongong
- Australia
| | - Fabien Goulay
- Department of Chemistry
- West Virginia University
- Morgantown
- USA
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13
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Koyama D, Coulter P, Grubb MP, Greetham GM, Clark IP, Orr-Ewing AJ. Reaction Dynamics of CN Radicals in Acetonitrile Solutions. J Phys Chem A 2015; 119:12924-34. [DOI: 10.1021/acs.jpca.5b10720] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Daisuke Koyama
- School
of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, U.K
| | - Philip Coulter
- School
of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, U.K
| | - Michael P. Grubb
- School
of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, U.K
| | - Gregory M. Greetham
- Central
Laser Facility, Research Complex at Harwell, Science and Technology
Facilities Council, Rutherford Appleton Laboratory, Harwell Oxford, Didcot, Oxfordshire OX11 0QX, U.K
| | - Ian P. Clark
- Central
Laser Facility, Research Complex at Harwell, Science and Technology
Facilities Council, Rutherford Appleton Laboratory, Harwell Oxford, Didcot, Oxfordshire OX11 0QX, U.K
| | - Andrew J. Orr-Ewing
- School
of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, U.K
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14
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Dunning GT, Preston TJ, Greaves SJ, Greetham GM, Clark IP, Orr-Ewing AJ. Vibrational Excitation of Both Products of the Reaction of CN Radicals with Acetone in Solution. J Phys Chem A 2015; 119:12090-101. [PMID: 26192334 PMCID: PMC4685429 DOI: 10.1021/acs.jpca.5b05624] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Transient electronic and vibrational absorption spectroscopy unravel the mechanisms and dynamics of bimolecular reactions of CN radicals with acetone in deuterated chloroform solutions. The CN radicals are produced by ultrafast ultraviolet photolysis of dissolved ICN. Two reactive forms of CN radicals are distinguished by their electronic absorption bands: "free" (uncomplexed) CN radicals, and "solvated" CN radicals that are complexed with solvent molecules. The lifetimes of the free CN radicals are limited to a few picoseconds following their photolytic production because of geminate recombination to ICN and INC, complexation with CDCl3 molecules, and reaction with acetone. The acetone reaction occurs with a rate coefficient of (8.0 ± 0.5) × 10(10) M(-1) s(-1) and transient vibrational spectra in the C═N and C═O stretching regions reveal that both the nascent HCN and 2-oxopropyl (CH3C(O)CH2) radical products are vibrationally excited. The rate coefficient for the reaction of solvated CN with acetone is 40 times slower than for free CN, with a rate coefficient of (2.0 ± 0.9) × 10(9) M(-1) s(-1) obtained from the rise in the HCN product v1(C═N stretch) IR absorption band. Evidence is also presented for CN complexes with acetone that are more strongly bound than the CN-CDCl3 complexes because of CN interactions with the carbonyl group. The rates of reactions of these more strongly associated radicals are slower still.
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Affiliation(s)
- Greg T Dunning
- School of Chemistry, University of Bristol , Cantock's Close, Bristol BS8 1TS, U.K
| | - Thomas J Preston
- School of Chemistry, University of Bristol , Cantock's Close, Bristol BS8 1TS, U.K
| | - Stuart J Greaves
- School of Engineering and Physical Sciences, Heriot-Watt University , Edinburgh EH14 4AS, U.K
| | - Gregory M Greetham
- Central Laser Facility, Research Complex at Harwell, Science and Technology Facilities Council, Rutherford Appleton Laboratory , Harwell Oxford, Didcot, Oxfordshire OX11 0QX, U.K
| | - Ian P Clark
- Central Laser Facility, Research Complex at Harwell, Science and Technology Facilities Council, Rutherford Appleton Laboratory , Harwell Oxford, Didcot, Oxfordshire OX11 0QX, U.K
| | - Andrew J Orr-Ewing
- School of Chemistry, University of Bristol , Cantock's Close, Bristol BS8 1TS, U.K
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15
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16
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Kirk BB, Savee JD, Trevitt AJ, Osborn DL, Wilson KR. Molecular weight growth in Titan's atmosphere: branching pathways for the reaction of 1-propynyl radical (H3CCC˙) with small alkenes and alkynes. Phys Chem Chem Phys 2015. [DOI: 10.1039/c5cp02589c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Reaction of 1-propynyl radical with propyne and propene yields primarily methyl loss over hydrogen elimination. The implications of this result on molecular weight growth in Titan's atmosphere are discussed.
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Affiliation(s)
- Benjamin B. Kirk
- Chemical Sciences Division
- Lawrence Berkeley National Laboratory
- Berkeley
- USA
| | - John D. Savee
- Combustion Research Facility
- Sandia National Laboratories
- Livermore
- USA
| | | | - David L. Osborn
- Combustion Research Facility
- Sandia National Laboratories
- Livermore
- USA
| | - Kevin R. Wilson
- Chemical Sciences Division
- Lawrence Berkeley National Laboratory
- Berkeley
- USA
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17
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Maity S, Dangi BB, Parker DSN, Kaiser RI, An Y, Sun BJ, Chang AHH. Combined crossed molecular beam and ab initio investigation of the multichannel reaction of boron monoxide (BO; X2Σ+) with Propylene (CH3CHCH2; X1A'): competing atomic hydrogen and methyl loss pathways. J Phys Chem A 2014; 118:9632-45. [PMID: 25238644 DOI: 10.1021/jp507001r] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The reaction dynamics of boron monoxide ((11)BO; X(2)Σ(+)) with propylene (CH(3)CHCH(2); X(1)A') were investigated under single collision conditions at a collision energy of 22.5 ± 1.3 kJ mol(-1). The crossed molecular beam investigation combined with ab initio electronic structure and statistical (RRKM) calculations reveals that the reaction follows indirect scattering dynamics and proceeds via the barrierless addition of boron monoxide radical with its radical center located at the boron atom. This addition takes place to either the terminal carbon atom (C1) and/or the central carbon atom (C2) of propylene reactant forming (11)BOC(3)H(6) intermediate(s). The long-lived (11)BOC(3)H(6) doublet intermediate(s) underwent unimolecular decomposition involving at least three competing reaction mechanisms via an atomic hydrogen loss from the vinyl group, an atomic hydrogen loss from the methyl group, and a methyl group elimination to form cis-/trans-1-propenyl-oxo-borane (CH(3)CHCH(11)BO), 3-propenyl-oxo-borane (CH(2)CHCH(2)(11)BO), and ethenyl-oxo-borane (CH(2)CH(11)BO), respectively. Utilizing partially deuterated propylene (CD(3)CHCH(2) and CH(3)CDCD(2)), we reveal that the loss of a vinyl hydrogen atom is the dominant hydrogen elimination pathway (85 ± 10%) forming cis-/trans-1-propenyl-oxo-borane, compared to the loss of a methyl hydrogen atom (15 ± 10%) leading to 3-propenyl-oxo-borane. The branching ratios for an atomic hydrogen loss from the vinyl group, an atomic hydrogen loss from the methyl group, and a methyl group loss are experimentally derived to be 26 ± 8%:5 ± 3%:69 ± 15%, respectively; these data correlate nicely with the branching ratios calculated via RRKM theory of 19%:5%:75%, respectively.
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Affiliation(s)
- Surajit Maity
- Department of Chemistry, University of Hawaii at Manoa , Honolulu, Hawaii 96822, United States
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18
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Farahani P, Maeda S, Francisco JS, Lundberg M. Mechanisms for the Breakdown of Halomethanes through Reactions with Ground-State Cyano Radicals. Chemphyschem 2014; 16:181-90. [DOI: 10.1002/cphc.201402601] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2014] [Indexed: 11/07/2022]
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19
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Salter RJ, Blitz MA, Heard DE, Kovács T, Pilling MJ, Rickard AR, Seakins PW. Quantum yields for the photolysis of glyoxal below 350 nm and parameterisations for its photolysis rate in the troposphere. Phys Chem Chem Phys 2013; 15:4984-94. [DOI: 10.1039/c3cp43597k] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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20
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Leonori F, Petrucci R, Wang X, Casavecchia P, Balucani N. A crossed beam study of the reaction CN+C2H4 at a high collision energy: The opening of a new reaction channel. Chem Phys Lett 2012. [DOI: 10.1016/j.cplett.2012.09.070] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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21
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Glowacki DR, Liang CH, Morley C, Pilling MJ, Robertson SH. MESMER: An Open-Source Master Equation Solver for Multi-Energy Well Reactions. J Phys Chem A 2012; 116:9545-60. [DOI: 10.1021/jp3051033] [Citation(s) in RCA: 397] [Impact Index Per Article: 33.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | - Chi-Hsiu Liang
- School of Chemistry, University of Leeds, Leeds LS2 9JT,
U.K
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22
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Gardez A, Saidani G, Biennier L, Georges R, Hugo E, Chandrasekaran V, Roussel V, Rowe B, Reddy KPJ, Arunan E. High-temperature kinetics of the reaction between CN and hydrocarbons using a novel high-enthalpy flow tube. INT J CHEM KINET 2012. [DOI: 10.1002/kin.20730] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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23
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Plane JMC, Whalley CL, Frances-Soriano L, Goddard A, Harvey JN, Glowacki DR, Viggiano AA. O2(a1Δg) + Mg, Fe, and Ca: Experimental kinetics and formulation of a weak collision, multiwell master equation with spin-hopping. J Chem Phys 2012; 137:014310. [DOI: 10.1063/1.4730423] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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24
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Feng W, Hershberger JF. Kinetics of the O + ICN Reaction. J Phys Chem A 2012; 116:4817-22. [DOI: 10.1021/jp302555p] [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)
- Wenhui Feng
- Department of Chemistry and Biochemistry, Department 2735, P.O. Box 6050, North Dakota State University, Fargo, North Dakota 58108-6050, United States
| | - John F. Hershberger
- Department of Chemistry and Biochemistry, Department 2735, P.O. Box 6050, North Dakota State University, Fargo, North Dakota 58108-6050, United States
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25
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Ito H, Araki H, Wada A, Yamamoto A, Suzuki T, Saitoh H. Sticking probability of CN(X2Σ+) radicals onto amorphous carbon nitride films formed from the decomposition of BrCN induced by the microwave discharge flow of Ar. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2012; 86:256-265. [PMID: 22057299 DOI: 10.1016/j.saa.2011.10.033] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2011] [Revised: 10/05/2011] [Accepted: 10/14/2011] [Indexed: 05/31/2023]
Abstract
The sticking probability, s, of CN(X(2)Σ(+)) radicals onto amorphous carbon nitride (a-CN(x)) films with high [N]/([N]+[C]) ratios (≤0.5) was evaluated. CN(X(2)Σ(+)) radicals were generated from the decomposition of BrCN with the microwave discharge flow of Ar in the two experimental configurations, I and II, where the distance between the tip of the nozzle introducing BrCN is close (≈10 mm) to and distant (≈0.3 m) from the laser-beam path or the Si substrate, respectively. For each configuration, s was evaluated both under the desiccated and H(2)O-added conditions from the number density of CN(X(2)Σ(+)) evaluated from the intensity of the CN(A(2)Π(i)-X(2)Σ(+)) laser-induced fluorescence spectrum calibrated against Rayleigh scattering intensity of Ar, the flow speed measured by a time-resolved emission, and the film mass. The [N]/([N]+[C]) ratios of films were evaluated as 0.4-0.5 and 0.3 in the configurations I and II, respectively, from the compositional analysis using Rutherford back scattering and elastic recoil detection analysis together with the XPS analysis. The variation of s under various experimental conditions was discussed based on the electron densities in the reaction region and the relative density of the hydrogen-termination structures of the film surface.
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Affiliation(s)
- Haruhiko Ito
- Department of Chemistry, Nagaoka University of Technology, Nagaoka, Niigata 940-2188, Japan
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26
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Blitz MA, Seakins PW. Laboratory studies of photochemistry and gas phase radical reaction kinetics relevant to planetary atmospheres. Chem Soc Rev 2012; 41:6318-47. [DOI: 10.1039/c2cs35204d] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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27
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Blitz MA, Talbi D, Seakins PW, Smith IWM. Rate Constants and Branching Ratios for the Reaction of CH Radicals with NH3: A Combined Experimental and Theoretical Study. J Phys Chem A 2011; 116:5877-85. [DOI: 10.1021/jp209383t] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Mark A. Blitz
- School of Chemistry, University of Leeds, Woodhouse Lane, Leeds, United Kingdom LS2 9JT
| | - Dahbia Talbi
- LUPM, Université de Montpelier II, CNRS, Place Eugène Bataillon, 34095 Montpelier cedex 05, France
| | - Paul W. Seakins
- School of Chemistry, University of Leeds, Woodhouse Lane, Leeds, United Kingdom LS2 9JT
| | - Ian W. M. Smith
- LUPM, Université de Montpelier II, CNRS, Place Eugène Bataillon, 34095 Montpelier cedex 05, France
- University Chemical Laboratories, Lensfield Road, Cambridge, United Kingdom CB2 1EW
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28
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Trevitt AJ, Soorkia S, Savee JD, Selby TS, Osborn DL, Taatjes CA, Leone SR. Branching Fractions of the CN + C3H6 Reaction Using Synchrotron Photoionization Mass Spectrometry: Evidence for the 3-Cyanopropene Product. J Phys Chem A 2011; 115:13467-73. [DOI: 10.1021/jp208496r] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Adam J. Trevitt
- School of Chemistry, University of Wollongong, NSW 2522, Australia
| | - Satchin Soorkia
- Departments of Chemistry and Physics, University of California, Berkeley, California 94720, United States
| | - John D. Savee
- Combustion Research Facility, Mail Stop 9055, Sandia National Laboratories, Livermore, California 94551, United States
| | - Talitha S. Selby
- Department of Chemistry, University of Wisconsin—Washington County, West Bend, Wisconsin 53095, United States
| | - David L. Osborn
- Combustion Research Facility, Mail Stop 9055, Sandia National Laboratories, Livermore, California 94551, United States
| | - Craig A. Taatjes
- Combustion Research Facility, Mail Stop 9055, Sandia National Laboratories, Livermore, California 94551, United States
| | - Stephen R. Leone
- Departments of Chemistry and Physics, University of California, Berkeley, California 94720, United States
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720, United States
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29
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Affiliation(s)
- Wenhui Feng
- Department of Chemistry and Biochemistry, Department 2735, P.O. Box 6050, North Dakota State University, Fargo, North Dakota 58108-6050, United States
| | - John F. Hershberger
- Department of Chemistry and Biochemistry, Department 2735, P.O. Box 6050, North Dakota State University, Fargo, North Dakota 58108-6050, United States
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30
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Carr SA, Glowacki DR, Liang CH, Baeza-Romero MT, Blitz MA, Pilling MJ, Seakins PW. Experimental and Modeling Studies of the Pressure and Temperature Dependences of the Kinetics and the OH Yields in the Acetyl + O2 Reaction. J Phys Chem A 2011; 115:1069-85. [DOI: 10.1021/jp1099199] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Scott A. Carr
- School of Chemistry and ‡School of Earth and Environment, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - David R. Glowacki
- School of Chemistry and ‡School of Earth and Environment, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Chi-Hsiu Liang
- School of Chemistry and ‡School of Earth and Environment, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - M. Teresa Baeza-Romero
- School of Chemistry and ‡School of Earth and Environment, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Mark A. Blitz
- School of Chemistry and ‡School of Earth and Environment, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Michael J. Pilling
- School of Chemistry and ‡School of Earth and Environment, University of Leeds, Leeds LS2 9JT, United Kingdom
| | - Paul W. Seakins
- School of Chemistry and ‡School of Earth and Environment, University of Leeds, Leeds LS2 9JT, United Kingdom
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31
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Gannon KL, Blitz MA, Liang CH, Pilling MJ, Seakins PW, Glowacki DR. Temperature Dependent Kinetics (195−798 K) and H Atom Yields (298−498 K) from Reactions of 1CH2 with Acetylene, Ethene, and Propene. J Phys Chem A 2010; 114:9413-24. [DOI: 10.1021/jp102276j] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- K. L. Gannon
- School of Chemistry, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - M. A. Blitz
- School of Chemistry, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - C. H. Liang
- School of Chemistry, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - M. J. Pilling
- School of Chemistry, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - P. W. Seakins
- School of Chemistry, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - D. R. Glowacki
- School of Chemistry, University of Leeds, Leeds, LS2 9JT, U.K., and School of Chemistry, Centre for Computational Chemistry, University of Bristol, Bristol, BS8 1TS, United Kingdom
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32
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Leonori F, Hickson KM, Le Picard SD, Wang X, Petrucci R, Foggi P, Balucani N, Casavecchia P. Crossed-beam universal-detection reactive scattering of radical beams characterized by laser-induced-fluorescence: the case of C2and CN. Mol Phys 2010. [DOI: 10.1080/00268971003657110] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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33
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Kovács T, Blitz MA, Seakins PW. H-Atom Yields from the Photolysis of Acetylene and from the Reaction of C2H with H2, C2H2, and C2H4. J Phys Chem A 2010; 114:4735-41. [DOI: 10.1021/jp908285t] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Tamás Kovács
- School of Chemistry, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - Mark A. Blitz
- School of Chemistry, University of Leeds, Leeds, LS2 9JT, United Kingdom
| | - Paul W. Seakins
- School of Chemistry, University of Leeds, Leeds, LS2 9JT, United Kingdom
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34
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Berteloite C, Le Picard SD, Balucani N, Canosa A, Sims IR. Low temperature rate coefficients for reactions of the butadiynyl radical, C4H, with various hydrocarbons. Part II: reactions with alkenes (ethylene, propene, 1-butene), dienes (allene, 1,3-butadiene) and alkynes (acetylene, propyne and 1-butyne). Phys Chem Chem Phys 2010; 12:3677-89. [DOI: 10.1039/b923867k] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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35
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Morales SB, Le Picard SD, Canosa A, Sims IR. Experimental measurements of low temperature rate coefficients for neutral–neutral reactions of interest for atmospheric chemistry of Titan, Pluto and Triton: Reactions of the CN radical. Faraday Discuss 2010; 147:155-71; discussion 251-82. [DOI: 10.1039/c004219f] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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36
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Hébrard E, Dobrijevic M, Pernot P, Carrasco N, Bergeat A, Hickson KM, Canosa A, Le Picard SD, Sims IR. How Measurements of Rate Coefficients at Low Temperature Increase the Predictivity of Photochemical Models of Titan’s Atmosphere. J Phys Chem A 2009; 113:11227-37. [DOI: 10.1021/jp905524e] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | | | - P. Pernot
- Laboratoire de Chimie Physique, UMR 8000, CNRS-Université Paris-Sud 11, Bât. 349, Orsay, F-91405, France
| | - N. Carrasco
- Laboratoire Atmosphères, Milieux, Observations Spatiales, UMR 8190, CNRS-IPSL-Université de Versailles Saint Quentin, BP 3, Verrières le Buisson, F-91371, France
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37
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Huang CH, Kaiser RI, Chang AHH. Theoretical Study on the Reaction of Ground State Cyano Radical with Propylene in Titan’s Atmosphere. J Phys Chem A 2009; 113:12675-85. [DOI: 10.1021/jp905081u] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- C. H. Huang
- Department of Chemistry, National Dong Hwa University, Shoufeng, Hualien 974, Taiwan, and Department of Chemistry, University of Hawaii at Manoa, Honolulu, Hawaii 96822
| | - R. I. Kaiser
- Department of Chemistry, National Dong Hwa University, Shoufeng, Hualien 974, Taiwan, and Department of Chemistry, University of Hawaii at Manoa, Honolulu, Hawaii 96822
| | - A. H. H. Chang
- Department of Chemistry, National Dong Hwa University, Shoufeng, Hualien 974, Taiwan, and Department of Chemistry, University of Hawaii at Manoa, Honolulu, Hawaii 96822
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38
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Frankcombe TJ, Smith SC. Numerical solution methods for large, difficult kinetic master equations. Theor Chem Acc 2009. [DOI: 10.1007/s00214-009-0623-z] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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39
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Balucani N. Elementary reactions and their role in gas-phase prebiotic chemistry. Int J Mol Sci 2009; 10:2304-2335. [PMID: 19564951 PMCID: PMC2695279 DOI: 10.3390/ijms10052304] [Citation(s) in RCA: 81] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2009] [Revised: 05/13/2009] [Accepted: 05/15/2009] [Indexed: 11/23/2022] Open
Abstract
The formation of complex organic molecules in a reactor filled with gaseous mixtures possibly reproducing the primitive terrestrial atmosphere and ocean demonstrated more than 50 years ago that inorganic synthesis of prebiotic molecules is possible, provided that some form of energy is provided to the system. After that groundbreaking experiment, gas-phase prebiotic molecules have been observed in a wide variety of extraterrestrial objects (including interstellar clouds, comets and planetary atmospheres) where the physical conditions vary widely. A thorough characterization of the chemical evolution of those objects relies on a multi-disciplinary approach: 1) observations allow us to identify the molecules and their number densities as they are nowadays; 2) the chemistry which lies behind their formation starting from atoms and simple molecules is accounted for by complex reaction networks; 3) for a realistic modeling of such networks, a number of experimental parameters are needed and, therefore, the relevant molecular processes should be fully characterized in laboratory experiments. A survey of the available literature reveals, however, that much information is still lacking if it is true that only a small percentage of the elementary reactions considered in the models have been characterized in laboratory experiments. New experimental approaches to characterize the relevant elementary reactions in laboratory are presented and the implications of the results are discussed.
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Affiliation(s)
- Nadia Balucani
- Dipartimento di Chimica, Università degli Studi di Perugia, 06123 Perugia, Italy; E-Mail:
; Tel. +39-075-585-5513; Fax: +39-075-585-5606
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40
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Glowacki DR, Wang L, Pilling MJ. Evidence of Formation of Bicyclic Species in the Early Stages of Atmospheric Benzene Oxidation. J Phys Chem A 2009; 113:5385-96. [DOI: 10.1021/jp9001466] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- David R. Glowacki
- School of Chemistry, University of Leeds, Leeds LS2 9JT, United Kingdom, and School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou, China, 51640
| | - Liming Wang
- School of Chemistry, University of Leeds, Leeds LS2 9JT, United Kingdom, and School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou, China, 51640
| | - Michael J. Pilling
- School of Chemistry, University of Leeds, Leeds LS2 9JT, United Kingdom, and School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou, China, 51640
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41
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Blitz MA, Seakins PW, Smith IWM. An experimental confirmation of the products of the reaction between CN radicals and NH3. Phys Chem Chem Phys 2009; 11:10824-6. [DOI: 10.1039/b917734e] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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42
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Gannon KL, Blitz MA, Pilling MJ, Seakins PW, Klippenstein SJ, Harding LB. Kinetics and product branching ratios of the reaction of (1)CH2 with H2 and D2. J Phys Chem A 2008; 112:9575-83. [PMID: 18714945 DOI: 10.1021/jp803038s] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The reactions of singlet methylene (a(1)A1 (1)CH2) with hydrogen and deuterium have been studied by experimental and theoretical techniques. The rate coefficients for the removal of singlet methylene with H2 (k1) and D2 (k2) have been measured from 195 to 798 K and are essentially temperature-independent with values of k1 = (10.48 +/- 0.32) x 10(-11) cm(3) molecule(-1) s(-1) and k2 = (5.98 +/- 0.34) x 10(-11) cm(3) molecule(-1) s(-1), where the errors represent 2sigma, giving a ratio of k1/k2 = 1.75 +/- 0.11. In the reaction with H2, singlet methylene can be removed by reaction giving CH3 + H or deactivated to ground-state triplet methylene. Direct measurement of the H atom product showed that the fraction of relaxation decreased from 0.3 at 195 K to essentially zero at 398 K. For the reaction with deuterium, either H or D may be eliminated. Experimentally, the H:D ratio was determined to be 1.8 +/- 0.5 over the range 195-398 K. Theoretically, the reaction kinetics has been predicted with variable reaction coordinate transition state theory and with rigid-body trajectory simulations employing various high-level, ab initio-determined potential energy surfaces. The magnitudes of the calculated rate coefficients are in agreement with experiment, but the calculations show a significant negative temperature dependence that is not observed in the experimental results. The calculated and experimental H to D ratios from the reaction of singlet methylene with D2 are in good agreement, suggesting that the reaction proceeds entirely through the formation of a long-lived methane intermediate with a statistical distribution of energy.
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Affiliation(s)
- K L Gannon
- School of Chemistry, University of Leeds, Leeds, LS2 9JT, United Kingdom
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43
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Gu X, Zhang F, Kaiser RI. Reaction dynamics on the formation of 1- and 3-cyanopropylene in the crossed beams reaction of ground-state cyano radicals (CN) with propylene (C3H6) and its deuterated isotopologues. J Phys Chem A 2008; 112:9607-13. [PMID: 18681396 DOI: 10.1021/jp8039059] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Crossed molecular beams experiments were utilized to explore the chemical reaction dynamics of ground-state cyano radicals, CN(X(2)Sigma(+)), with propylene (CH3CHCH2) together with two d3-isotopologues (CD3CHCH2, CH3CDCD2) as potential pathways to form organic nitriles under single collision conditions in the atmosphere of Saturn's moon Titan and in the interstellar medium. On the basis of the center-of-mass translational and angular distributions, the reaction dynamics were deduced to be indirect and commenced via an addition of the electrophilic cyano radical with its radical center to the alpha-carbon atom of the propylene molecule yielding a doublet radical intermediate: CH3CHCH2CN. Crossed beam experiments with propylene-1,1,2-d3 (CH3CDCD2) and propylene-3,3,3-d3 (CD3CHCH2) indicated that the reaction intermediates CH3CDCD2CN (from propylene-1,1,2-d3) and CD3CHCH2CN (from propylene-3,3,3-d3) eject both atomic hydrogen through tight exit transition states located about 40-50 kJ mol(-1) above the separated products: 3-butenenitrile [H2CCDCD2CN] (25%), and cis/trans-2-butenenitrile [CD3CHCHCN] (75%), respectively, plus atomic hydrogen. Applications of our results to the chemical processing of cold molecular clouds like TMC-1 and OMC-1 are also presented.
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Affiliation(s)
- Xibin Gu
- Department of Chemistry, University of Hawaii at Manoa, Honolulu, Hawaii 96822, USA
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Páramo A, Canosa A, Le Picard SD, Sims IR. Rate Coefficients for the Reactions of C2(a3Πu) and C2(X1Σg+) with Various Hydrocarbons (CH4, C2H2, C2H4, C2H6, and C3H8): A Gas-Phase Experimental Study over the Temperature Range 24−300 K. J Phys Chem A 2008; 112:9591-600. [DOI: 10.1021/jp8025336] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Alejandra Páramo
- Institut de Physique de Rennes, UMR CNRS−Université n° 6251; Equipe ”Astrochimie Expérimentale”, Campus de Beaulieu, Bât. 11C, Université de Rennes 1, 35042 Rennes Cedex, France, and School of Chemistry, University of Birmingham, Edgbaston B15 2TT, Birmingham, U.K
| | - André Canosa
- Institut de Physique de Rennes, UMR CNRS−Université n° 6251; Equipe ”Astrochimie Expérimentale”, Campus de Beaulieu, Bât. 11C, Université de Rennes 1, 35042 Rennes Cedex, France, and School of Chemistry, University of Birmingham, Edgbaston B15 2TT, Birmingham, U.K
| | - Sébastien D. Le Picard
- Institut de Physique de Rennes, UMR CNRS−Université n° 6251; Equipe ”Astrochimie Expérimentale”, Campus de Beaulieu, Bât. 11C, Université de Rennes 1, 35042 Rennes Cedex, France, and School of Chemistry, University of Birmingham, Edgbaston B15 2TT, Birmingham, U.K
| | - Ian R. Sims
- Institut de Physique de Rennes, UMR CNRS−Université n° 6251; Equipe ”Astrochimie Expérimentale”, Campus de Beaulieu, Bât. 11C, Université de Rennes 1, 35042 Rennes Cedex, France, and School of Chemistry, University of Birmingham, Edgbaston B15 2TT, Birmingham, U.K
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