1
|
Thawoos S, Suas-David N, Gurusinghe RM, Edlin M, Behzadfar A, Lang J, Suits AG. Low temperature reaction kinetics inside an extended Laval nozzle: REMPI characterization and detection by broadband rotational spectroscopy. J Chem Phys 2023; 159:214201. [PMID: 38054511 DOI: 10.1063/5.0178533] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Accepted: 11/06/2023] [Indexed: 12/07/2023] Open
Abstract
Chirped-Pulse Fourier-Transform millimeter wave (CP-FTmmW) spectroscopy is a powerful method that enables detection of quantum state specific reactants and products in mixtures. We have successfully coupled this technique with a pulsed uniform Laval flow system to study photodissociation and reactions at low temperature, which we refer to as CPUF ("Chirped-Pulse/Uniform flow"). Detection by CPUF requires monitoring the free induction decay (FID) of the rotational coherence. However, the high collision frequency in high-density uniform supersonic flows can interfere with the FID and attenuate the signal. One way to overcome this is to sample the flow, but this can cause interference from shocks in the sampling region. This led us to develop an extended Laval nozzle that creates a uniform flow within the nozzle itself, after which the gas undergoes a shock-free secondary expansion to cold, low pressure conditions ideal for CP-FTmmW detection. Impact pressure measurements, commonly used to characterize Laval flows, cannot be used to monitor the flow within the nozzle. Therefore, we implemented a REMPI (resonance-enhanced multiphoton ionization) detection scheme that allows the interrogation of the conditions of the flow directly inside the extended nozzle, confirming the fluid dynamics simulations of the flow environment. We describe the development of the new 20 K extended flow, along with its characterization using REMPI and computational fluid dynamics. Finally, we demonstrate its application to the first low temperature measurement of the reaction kinetics of HCO with O2 and obtain a rate coefficient at 20 K of 6.66 ± 0.47 × 10-11 cm3 molec-1 s-1.
Collapse
Affiliation(s)
- Shameemah Thawoos
- Department of Chemistry, University of Missouri, Columbia, Missouri 65211, USA
| | - Nicolas Suas-David
- Univ Rennes, CNRS, Institut de Physique de Rennes - UMR 6251, F-35000 Rennes, France
| | - Ranil M Gurusinghe
- Department of Chemistry, University of Missouri, Columbia, Missouri 65211, USA
- Department of Chemistry, Tennessee Tech University, Cookeville, Tennessee 38505, USA
| | - Matthew Edlin
- Department of Chemistry, University of Missouri, Columbia, Missouri 65211, USA
| | - Abbas Behzadfar
- Department of Chemistry, University of Missouri, Columbia, Missouri 65211, USA
| | - Jinxin Lang
- Department of Chemistry, University of Missouri, Columbia, Missouri 65211, USA
| | - Arthur G Suits
- Department of Chemistry, University of Missouri, Columbia, Missouri 65211, USA
| |
Collapse
|
2
|
Roy MMD, Omaña AA, Wilson ASS, Hill MS, Aldridge S, Rivard E. Molecular Main Group Metal Hydrides. Chem Rev 2021; 121:12784-12965. [PMID: 34450005 DOI: 10.1021/acs.chemrev.1c00278] [Citation(s) in RCA: 132] [Impact Index Per Article: 44.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
This review serves to document advances in the synthesis, versatile bonding, and reactivity of molecular main group metal hydrides within Groups 1, 2, and 12-16. Particular attention will be given to the emerging use of said hydrides in the rapidly expanding field of Main Group element-mediated catalysis. While this review is comprehensive in nature, focus will be given to research appearing in the open literature since 2001.
Collapse
Affiliation(s)
- Matthew M D Roy
- Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QR, United Kingdom
| | - Alvaro A Omaña
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, Alberta T6G 2G2, Canada
| | - Andrew S S Wilson
- Department of Chemistry, University of Bath, Avon BA2 7AY, United Kingdom
| | - Michael S Hill
- Department of Chemistry, University of Bath, Avon BA2 7AY, United Kingdom
| | - Simon Aldridge
- Inorganic Chemistry Laboratory, Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QR, United Kingdom
| | - Eric Rivard
- Department of Chemistry, University of Alberta, 11227 Saskatchewan Drive, Edmonton, Alberta T6G 2G2, Canada
| |
Collapse
|
3
|
Caster KL, Selby TM, Osborn DL, Le Picard SD, Goulay F. Product Detection of the CH(X 2Π) Radical Reaction with Cyclopentadiene: A Novel Route to Benzene. J Phys Chem A 2021; 125:6927-6939. [PMID: 34374546 DOI: 10.1021/acs.jpca.1c03517] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The reaction of the methylidyne radical (CH(X2Π)) with cyclopentadiene (c-C5H6) is studied in the gas phase at 4 Torr and 373 K using a multiplexed photoionization mass spectrometer. Under multiple collision conditions, the dominant product channel observed is the formation of C6H6 + H. Fitting the photoionization spectrum using reference spectra allows for isomeric resolution of C6H6 isomers, where benzene is the largest contributor with a relative branching fraction of 90 (±5)%. Several other C6H6 isomers are found to have smaller contributions, including fulvene with a branching fraction of 8 (±5)%. Master Equation calculations for four different entrance channels on the C6H7 potential energy surface are performed to explore the competition between CH cycloaddition to a C═C bond vs CH insertion into C-H bonds of cyclopentadiene. Previous studies on CH addition to unsaturated hydrocarbons show little evidence for the C-H insertion pathway. The present computed branching fractions support benzene as the sole cyclic product from CH cycloaddition, whereas fulvene is the dominant product from two of the three pathways for CH insertion into the C-H bonds of cyclopentadiene. The combination of experiment with Master Equation calculations implies that insertion must account for ∼10 (±5)% of the overall CH + cyclopentadiene mechanism.
Collapse
Affiliation(s)
- Kacee L Caster
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia 26506, United States
| | - Talitha M Selby
- Department of Mathematics and Natural Sciences, University of Wisconsin-Milwaukee, West Bend, Wisconsin 53095, United States
| | - David L Osborn
- Combustion Research Facility, Sandia National Laboratories, Mail Stop 9055, Livermore, California 94551, United States
| | - Sebastien D Le Picard
- IPR (Institut de Physique de Rennes), UMR 6251, Univ Rennes, CNRS, F-35000 Rennes, France
| | - Fabien Goulay
- C. Eugene Bennett Department of Chemistry, West Virginia University, Morgantown, West Virginia 26506, United States
| |
Collapse
|
4
|
Bourgalais J, Carrasco N, Vettier L, Comby A, Descamps D, Petit S, Blanchet V, Gaudin J, Mairesse Y, Marty B. Aromatic Formation Promoted by Ion-Driven Radical Pathways in EUV Photochemical Experiments Simulating Titan's Atmospheric Chemistry. J Phys Chem A 2021; 125:3159-3168. [PMID: 33843236 DOI: 10.1021/acs.jpca.1c00324] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
In the atmosphere of Titan, Saturn's main satellite, molecular growth is initiated by 85.6 nm extreme ultraviolet (EUV) photons triggering a chemistry with charged and free-radical species. However, the respective contribution of these species to the complexification of matter is far from being known. This work presents a chemical analysis in order to contribute to a better understanding of aromatic formation pathways. A gas mixture of N2/CH4 (90/10%) within the closed SURFACAT reactor was irradiated at a relatively low pressure (0.1 mbar) and room temperature for 6 h by EUV photons (∼85.6 nm). The neutral molecules formed at the end of the irradiation were condensed in a cryogenic trap and analyzed by electron ionization mass spectrometry. An analysis of the dominant chemical pathways highlights the identification of benzene and toluene and underlies the importance of small ion and radical reactions. On the basis of the experimental results, a speculative mechanism based on sequential H-elimination/CH3-addition reactions is proposed for the growth of aromatics in Titan's atmosphere. Elementary reactions to be studied are given to instill future updates of photochemical models of Titan's atmosphere.
Collapse
Affiliation(s)
- Jérémy Bourgalais
- LATMOS-IPSL, Université Versailles St-Quentin, CNRS/INSU, Sorbonne Université, UPMC Univ. Paris 06, 11 boulevard d'Alembert, 78280 Guyancourt, France.,Centre de Recherches Pétrographiques et Géochimiques, UMR 7358 CNRS-Université de Lorraine, 15 rue Notre Dame des Pauvres, BP 20, F-54501 Vandoeuvre-lès-Nancy, France
| | - Nathalie Carrasco
- LATMOS-IPSL, Université Versailles St-Quentin, CNRS/INSU, Sorbonne Université, UPMC Univ. Paris 06, 11 boulevard d'Alembert, 78280 Guyancourt, France
| | - Ludovic Vettier
- LATMOS-IPSL, Université Versailles St-Quentin, CNRS/INSU, Sorbonne Université, UPMC Univ. Paris 06, 11 boulevard d'Alembert, 78280 Guyancourt, France
| | - Antoine Comby
- CELIA, Université de Bordeaux - CNRS - CEA, UMR5107, 351 Cours de la Libération, F33405 Talence, France
| | - Dominique Descamps
- CELIA, Université de Bordeaux - CNRS - CEA, UMR5107, 351 Cours de la Libération, F33405 Talence, France
| | - Stéphane Petit
- CELIA, Université de Bordeaux - CNRS - CEA, UMR5107, 351 Cours de la Libération, F33405 Talence, France
| | - Valérie Blanchet
- CELIA, Université de Bordeaux - CNRS - CEA, UMR5107, 351 Cours de la Libération, F33405 Talence, France
| | - Jérôme Gaudin
- CELIA, Université de Bordeaux - CNRS - CEA, UMR5107, 351 Cours de la Libération, F33405 Talence, France
| | - Yann Mairesse
- CELIA, Université de Bordeaux - CNRS - CEA, UMR5107, 351 Cours de la Libération, F33405 Talence, France
| | - Bernard Marty
- Centre de Recherches Pétrographiques et Géochimiques, UMR 7358 CNRS - Université de Lorraine, 15 rue Notre Dame des Pauvres, BP 20, F-54501 Vandoeuvre-lès-Nancy, France
| |
Collapse
|
5
|
Abplanalp MJ, Góbi S, Kaiser RI. On the formation and the isomer specific detection of methylacetylene (CH 3CCH), propene (CH 3CHCH 2), cyclopropane (c-C 3H 6), vinylacetylene (CH 2CHCCH), and 1,3-butadiene (CH 2CHCHCH 2) from interstellar methane ice analogues. Phys Chem Chem Phys 2019; 21:5378-5393. [PMID: 30221272 DOI: 10.1039/c8cp03921f] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Pure methane (CH4) ices processed by energetic electrons under ultra-high vacuum conditions to simulate secondary electrons formed via galactic cosmic rays (GCRs) penetrating interstellar ice mantles have been shown to produce an array of complex hydrocarbons with the general formulae: CnH2n+2 (n = 4-8), CnH2n (n = 3-9), CnH2n-2 (n = 3-9), CnH2n-4 (n = 4-9), and CnH2n-6 (n = 6-7). By monitoring the in situ chemical evolution of the ice combined with temperature programmed desorption (TPD) studies and tunable single photon ionization coupled to a reflectron time-of-flight mass spectrometer, specific isomers of C3H4, C3H6, C4H4, and C4H6 were probed. These experiments confirmed the synthesis of methylacetylene (CH3CCH), propene (CH3CHCH2), cyclopropane (c-C3H6), vinylacetylene (CH2CHCCH), 1-butyne (HCCC2H5), 2-butyne (CH3CCCH3), 1,2-butadiene (H2CCCH(CH3)), and 1,3-butadiene (CH2CHCHCH2) with yields of 2.17 ± 0.95 × 10-4, 3.7 ± 1.5 × 10-3, 1.23 ± 0.77 × 10-4, 1.28 ± 0.65 × 10-4, 4.01 ± 1.98 × 10-5, 1.97 ± 0.98 × 10-4, 1.90 ± 0.84 × 10-5, and 1.41 ± 0.72 × 10-4 molecules eV-1, respectively. Mechanistic studies exploring the formation routes of methylacetylene, propene, and vinylacetylene were also conducted, and revealed the additional formation of the 1,2,3-butatriene isomer. Several of the above isomers, methylacetylene, propene, vinylacetylene, and 1,3-butadiene, have repeatedly been shown to be important precursors in the formation of polycyclic aromatic hydrocarbons (PAHs), but until now their interstellar synthesis has remained elusive.
Collapse
Affiliation(s)
- Matthew J Abplanalp
- W. M. Keck Research Laboratory in Astrochemistry, University of Hawaii at Manoa, Honolulu, HI 96822, USA.
| | | | | |
Collapse
|
6
|
Metz RB, Altinay G, Kostko O, Ahmed M. Probing Reactivity of Gold Atoms with Acetylene and Ethylene with VUV Photoionization Mass Spectrometry and Ab Initio Studies. J Phys Chem A 2019; 123:2194-2202. [DOI: 10.1021/acs.jpca.8b12560] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ricardo B. Metz
- Department of Chemistry, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
| | - Gokhan Altinay
- Department of Chemistry, University of Massachusetts Amherst, Amherst, Massachusetts 01003, United States
| | - Oleg Kostko
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Musahid Ahmed
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| |
Collapse
|
7
|
Abplanalp MJ, Jones BM, Kaiser RI. Untangling the methane chemistry in interstellar and solar system ices toward ionizing radiation: a combined infrared and reflectron time-of-flight analysis. Phys Chem Chem Phys 2018; 20:5435-5468. [PMID: 28972622 DOI: 10.1039/c7cp05882a] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Pure methane (CH4/CD4) ices were exposed to three ionizing radiation sources at 5.5 K under ultrahigh vacuum conditions to compare the complex hydrocarbon spectrum produced across several interstellar environments. These irradiation sources consisted of energetic electrons to simulate secondary electrons formed in the track of galactic cosmic rays (GCRs), Lyman α (10.2 eV; 121.6 nm) photons simulated the internal VUV field in a dense cloud, and broadband (112.7-169.8 nm; 11.0-7.3 eV) photons which mimic the interstellar ultra-violet field. The in situ chemical evolution of the ices was monitored via Fourier transform infrared spectroscopy (FTIR) and during heating via mass spectrometry utilizing a quadrupole mass spectrometer with an electron impact ionization source (EI-QMS) and a reflectron time-of-flight mass spectrometer with a photoionization source (PI-ReTOF-MS). The FTIR analysis detected six small hydrocarbon products from the three different irradiation sources: propane [C3H8(C3D8)], ethane [C2H6(C2D6)], the ethyl radical [C2H5(C2D5)], ethylene [C2H4(C2D4)], acetylene [C2H2(C2D2)], and the methyl radical [CH3(CD3)]. The sensitive PI-ReTOF-MS analysis identified a complex array of products with different products being detected between experiments with general formulae: CnH2n+2 (n = 4-8), CnH2n (n = 3-9), CnH2n-2 (n = 3-9), CnH2n-4 (n = 4-9), and CnH2n-6 (n = 6-7) from electron irradiation and CnH2n+2 (n = 4-8), CnH2n (n = 3-10), CnH2n-2 (n = 3-11), CnH2n-4 (n = 4-11), CnH2n-6 (n = 5-11), and CnH2n-8 (n = 6-11) from broadband photolysis and Lyman α photolysis. These experiments show that even the simplest hydrocarbon can produce important complex hydrocarbons such as C3H4 and C4H6 isomers. Distinct isomers from these groups have been shown to be important reactants in the synthesis of polycyclic aromatic hydrocarbons like indene (C9H8) and naphthalene (C10H8) under interstellar conditions.
Collapse
Affiliation(s)
- Matthew J Abplanalp
- W. M. Keck Research Laboratory in Astrochemistry, University of Hawaii at Manoa, Honolulu, Hawaii, HI 96822, USA.
| | | | | |
Collapse
|
8
|
Ryazantsev SV, Tarroni R, Feldman VI, Khriachtchev L. Effect of Noncovalent Interactions on Vibronic Transitions: An Experimental and Theoretical Study of the C2
H⋅⋅⋅CO2
Complex. Chemphyschem 2017; 18:949-958. [DOI: 10.1002/cphc.201601441] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2016] [Revised: 01/20/2017] [Indexed: 11/11/2022]
Affiliation(s)
- Sergey V. Ryazantsev
- Department of Chemistry; University of Helsinki; P. O. Box 55 FI-00014 Helsinki Finland
- Department of Chemistry; Lomonosov Moscow State University; Moscow 119991 Russia
| | - Riccardo Tarroni
- Dipartimento di Chimica Industriale “Toso Montanari”; Università di Bologna, Viale; Risorgimento 4 40136 Bologna Italy
| | - Vladimir I. Feldman
- Department of Chemistry; Lomonosov Moscow State University; Moscow 119991 Russia
| | - Leonid Khriachtchev
- Department of Chemistry; University of Helsinki; P. O. Box 55 FI-00014 Helsinki Finland
| |
Collapse
|
9
|
Smith KJ, Meloni G. Influence of various functional groups on the relative stability of alkylperoxy triplet cations: A theoretical study. Chem Phys Lett 2015. [DOI: 10.1016/j.cplett.2015.05.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
|
10
|
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.
Collapse
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
| |
Collapse
|
11
|
Capron M, Bourgalais J, Abhinavam Kailasanathan RK, Osborn DL, Le Picard SD, Goulay F. Flow tube studies of the C(3P) reactions with ethylene and propylene. Phys Chem Chem Phys 2015; 17:23833-46. [DOI: 10.1039/c5cp03918e] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Product detection studies of C(3P) atom reactions with ethylene, C2H4(X1Ag) and propylene, C3H6(X1A′) are carried out in a flow tube reactor at 332 K and 4 Torr (553.3 Pa) under multiple collision conditions.
Collapse
Affiliation(s)
- Michael Capron
- Institut de Physique de Rennes
- Département de Physique Moléculaire
- Astrophysique de Laboratoire
- 35042 Rennes Cedex
- France
| | - Jérémy Bourgalais
- Institut de Physique de Rennes
- Département de Physique Moléculaire
- Astrophysique de Laboratoire
- 35042 Rennes Cedex
- France
| | | | - David L. Osborn
- Combustion Research Facility
- Sandia National Laboratories
- Livermore
- USA
| | - Sébastien D. Le Picard
- Institut de Physique de Rennes
- Département de Physique Moléculaire
- Astrophysique de Laboratoire
- 35042 Rennes Cedex
- France
| | - Fabien Goulay
- Department of Chemistry
- West Virginia University
- Morgantown
- USA
| |
Collapse
|
12
|
Troy TP, Tayebjee MJ, Nauta K, Kable SH, Schmidt TW. Atmospheric oxidation intermediates: Laser spectroscopy of resonance-stabilized radicals from p-cymene. Chem Phys Lett 2015. [DOI: 10.1016/j.cplett.2014.12.007] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
|
13
|
Krechkivska O, Wilcox C, O’Connor GD, Nauta K, Kable SH, Schmidt TW. Ionization Energies of Three Resonance-Stabilized Radicals: Cyclohexadienyl (dn, n = 0, 1, 6, 7), 1-Phenylpropargyl, and Methylcyclohexadienyl. J Phys Chem A 2014; 118:10252-8. [DOI: 10.1021/jp508985s] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Olha Krechkivska
- School
of Chemistry, UNSW Sydney, Sydney, New South Wales 2052, Australia
| | - Callan Wilcox
- School
of Chemistry, UNSW Sydney, Sydney, New South Wales 2052, Australia
| | - Gerard D. O’Connor
- School
of Chemistry, The University of Sydney, Sydney, New South Wales 2006, Australia
| | - Klaas Nauta
- School
of Chemistry, UNSW Sydney, Sydney, New South Wales 2052, Australia
| | - Scott H. Kable
- School
of Chemistry, UNSW Sydney, Sydney, New South Wales 2052, Australia
| | - Timothy W. Schmidt
- School
of Chemistry, UNSW Sydney, Sydney, New South Wales 2052, Australia
| |
Collapse
|
14
|
Lockyear JF, Welz O, Savee JD, Goulay F, Trevitt AJ, Taatjes CA, Osborn DL, Leone SR. Isomer Specific Product Detection in the Reaction of CH with Acrolein. J Phys Chem A 2013; 117:11013-26. [DOI: 10.1021/jp407428v] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Affiliation(s)
- Jessica F. Lockyear
- Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720, United States
| | - Oliver Welz
- Combustion
Research Facility, Mail Stop 9055, Sandia National Laboratories, Livermore, California, 94551, United States
| | - John D. Savee
- Combustion
Research Facility, Mail Stop 9055, Sandia National Laboratories, Livermore, California, 94551, United States
| | - Fabien Goulay
- Department
of Chemistry, West Virginia University, Morgantown, West Virginia, 26506, United States
| | - Adam J. Trevitt
- School
of Chemistry, University of Wollongong, Wollongong, NSW 2522 Australia
| | - Craig A. Taatjes
- Combustion
Research Facility, Mail Stop 9055, Sandia National Laboratories, Livermore, California, 94551, United States
| | - David L. Osborn
- Combustion
Research Facility, Mail Stop 9055, Sandia National Laboratories, Livermore, California, 94551, United States
| | - Stephen R. Leone
- Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720, United States
- Departments
of Chemistry and Physics, University of California, Berkeley, California 94720, United States
| |
Collapse
|
15
|
Goulay F, Derakhshan A, Maher E, Trevitt AJ, Savee JD, Scheer AM, Osborn DL, Taatjes CA. Formation of dimethylketene and methacrolein by reaction of the CH radical with acetone. Phys Chem Chem Phys 2013; 15:4049-58. [PMID: 23403615 DOI: 10.1039/c3cp43829e] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The reaction of the methylidyne radical (CH) with acetone ((CH(3))(2)C[double bond, length as m-dash]O) is studied at room temperature and at a pressure of 4 Torr (533.3 Pa) using a multiplexed photoionization mass spectrometer coupled to the tunable vacuum ultraviolet synchrotron radiation of the Advanced Light Source at Lawrence Berkeley National Laboratory. The CH radicals are generated by 248 nm multiphoton photolysis of bromoform and react with acetone in an excess of helium and nitrogen gas flow. The main observed reaction exit channel is elimination of a hydrogen atom to form C(4)H(6)O isomers. Analysis of photoionization spectra identifies dimethylketene and methacrolein as the only H-elimination products. The best fit to the data gives branching ratios of 0.68 ± 0.14 for methacrolein and 0.32 ± 0.07 for dimethylketene. A methylketene spectrum measured here is used to reanalyze the photoionization spectrum obtained at m/z = 56 for the CH + acetaldehyde reaction, (Goulay et al., J. Phys. Chem. A, 2012, 116, 6091) yielding new H-loss branching ratios of 0.61 ± 0.12 for acrolein and 0.39 ± 0.08 for methylketene. The contribution from methyleneoxirane to the reaction product distribution is revised to be negligible. Coupled with additional product detection for the CD + acetone reaction, these observations pave the way for development of general set of reaction mechanisms for the addition of CH to compounds containing an acetyl subgroup.
Collapse
Affiliation(s)
- Fabien Goulay
- Department of Chemistry, West Virginia University, Morgantown, West Virginia 26506, USA.
| | | | | | | | | | | | | | | |
Collapse
|
16
|
Bouwman J, Fournier M, Sims IR, Leone SR, Wilson KR. Reaction Rate and Isomer-Specific Product Branching Ratios of C2H + C4H8: 1-Butene, cis-2-Butene, trans-2-Butene, and Isobutene at 79 K. J Phys Chem A 2013; 117:5093-105. [DOI: 10.1021/jp403637t] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Jordy Bouwman
- Departments of Chemistry and
Physics, University of California, Berkeley,
California 94720, United States
| | - Martin Fournier
- Institut de Physique de Rennes,
UMR 6251 du CNRS, Université de Rennes 1, 263 Avenue du Général Leclerc, 35042 Rennes Cedex,
France
| | - Ian R. Sims
- Institut de Physique de Rennes,
UMR 6251 du CNRS, Université de Rennes 1, 263 Avenue du Général Leclerc, 35042 Rennes Cedex,
France
| | - 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
| | - Kevin R. Wilson
- Chemical Sciences
Division, Lawrence Berkeley National Laboratory, 1 Cyclotron
Road, Berkeley, California 94720, United States
| |
Collapse
|
17
|
Balucani N, Skouteris D, Leonori F, Petrucci R, Hamberg M, Geppert WD, Casavecchia P, Rosi M. Combined crossed beam and theoretical studies of the N(2D) + C2H4 reaction and implications for atmospheric models of Titan. J Phys Chem A 2012; 116:10467-79. [PMID: 23016665 DOI: 10.1021/jp3072316] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The dynamics of the H displacement channels in the reaction N((2)D) + C(2)H(4) have been investigated by the crossed molecular beam technique with mass spectrometric detection and time-of-flight analysis at two different collision energies (17.2 and 28.2 kJ/mol). The interpretation of the scattering results is assisted by new electronic structure calculations of stationary points and product energetics for the C(2)H(4)N ground state doublet potential energy surface. RRKM statistical calculations have been performed to derive the product branching ratio under the conditions of the present experiments and of the atmosphere of Titan. Similarities and differences with respect to a recent study performed in crossed beam experiments coupled to ionization via tunable VUV synchrotron radiation are discussed (Lee, S.-H.; et al. Phys. Chem. Chem. Phys.2011, 13, 8515-8525). Implications for the atmospheric chemistry of Titan are presented.
Collapse
Affiliation(s)
- Nadia Balucani
- Dipartimento di Chimica, Università degli Studi di Perugia, 06123 Perugia, Italy.
| | | | | | | | | | | | | | | |
Collapse
|
18
|
Ray AW, Taatjes CA, Welz O, Osborn DL, Meloni G. Synchrotron photoionization measurements of OH-initiated cyclohexene oxidation: ring-preserving products in OH + cyclohexene and hydroxycyclohexyl + O2 reactions. J Phys Chem A 2012; 116:6720-30. [PMID: 22631211 DOI: 10.1021/jp3022437] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Earlier synchrotron photoionization mass spectrometry experiments suggested a prominent ring-opening channel in the OH-initiated oxidation of cyclohexene, based on comparison of product photoionization spectra with calculated spectra of possible isomers. The present work re-examines the OH + cyclohexene reaction, measuring the isomeric products of OH-initiated oxidation of partially and fully deuterated cyclohexene. In particular, the directly measured photoionization spectrum of 2-cyclohexen-1-ol differs substantially from the previously calculated Franck-Condon envelope, and the product spectrum can be fit with no contribution from ring-opening. Measurements of H(2)O(2) photolysis in the presence of C(6)D(10) establish that the addition-elimination product incorporates the hydrogen atom from the hydroxyl radical reactant and loses a hydrogen (a D atom in this case) from the ring. Investigation of OH + cyclohexene-4,4,5,5-d(4) confirms this result and allows mass discrimination of different abstraction pathways. Products of 2-hydroxycyclohexyl-d(10) reaction with O(2) are observed upon adding a large excess of O(2) to the OH + C(6)D(10) system.
Collapse
Affiliation(s)
- Amelia W Ray
- Department of Chemistry, University of San Francisco, San Francisco, California 94117, USA
| | | | | | | | | |
Collapse
|
19
|
Bouwman J, Goulay F, Leone SR, Wilson KR. Bimolecular rate constant and product branching ratio measurements for the reaction of C2H with ethene and propene at 79 K. J Phys Chem A 2012; 116:3907-17. [PMID: 22429068 DOI: 10.1021/jp301015b] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The reactions of the ethynyl radical (C(2)H) with ethene (C(2)H(4)) and propene (C(3)H(6)) are studied under low temperature conditions (79 K) in a pulsed Laval nozzle apparatus. Ethynyl radicals are formed by 193 nm photolysis of acetylene (C(2)H(2)) and the reactions are studied in nitrogen as a carrier gas. Reaction products are sampled and subsequently photoionized by the tunable vacuum ultraviolet radiation of the Advanced Light Source (ALS) at Lawrence Berkeley National Laboratory. The product ions are detected mass selectively and time-resolved by a quadrupole mass spectrometer. Bimolecular rate coefficients are determined under pseudo-first-order conditions, yielding values in good agreement with previous measurements. Photoionization spectra are measured by scanning the ALS photon energy while detecting the ionized reaction products. Analysis of the photoionization spectra yields-for the first time-low temperature isomer resolved product branching ratios. The reaction between C(2)H and ethene is found to proceed by H-loss and yields 100% vinylacetylene. The reaction between C(2)H and propene results in (85 ± 10)% C(4)H(4) (m/z = 52) via CH(3)-loss and (15 ± 10)% C(5)H(6) (m/z = 66) by H-loss. The C(4)H(4) channel is found to consist of 100% vinylacetylene. For the C(5)H(6) channel, analysis of the photoionization spectrum reveals that (62 ± 16)% is in the form of 4-penten-1-yne, (27 ± 8)% is in the form of cis- and trans-3-penten-1-yne and (11 ± 10)% is in the form of 2-methyl-1-buten-3-yne.
Collapse
Affiliation(s)
- Jordy Bouwman
- Department of Chemistry, University of California Berkeley, Berkeley, California 94720, USA
| | | | | | | |
Collapse
|
20
|
Goulay F, Trevitt AJ, Savee JD, Bouwman J, Osborn DL, Taatjes CA, Wilson KR, Leone SR. Product Detection of the CH Radical Reaction with Acetaldehyde. J Phys Chem A 2012; 116:6091-106. [DOI: 10.1021/jp2113126] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
| | - Adam J. Trevitt
- School of Chemistry, University of Wollongong, Wollongong, NSW 2522, Australia
| | - John D. Savee
- Combustion Research Facility, Mail Stop 9055, Sandia National Laboratories, Livermore, California 94551,
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
| | - Kevin R. Wilson
- Chemical
Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720, United States
| | - Stephen R. Leone
- Chemical
Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720, United States
| |
Collapse
|
21
|
Kaiser RI, Mebel AM. On the formation of polyacetylenes and cyanopolyacetylenes in Titan's atmosphere and their role in astrobiology. Chem Soc Rev 2012; 41:5490-501. [DOI: 10.1039/c2cs35068h] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
22
|
Nguyen VS, Elsamra RMI, Peeters J, Carl SA, Nguyen MT. Experimental and theoretical study of the reaction of the ethynyl radical with nitrous oxide, C2H + N2O. Phys Chem Chem Phys 2012; 14:7456-70. [PMID: 22517118 DOI: 10.1039/c2cp40367f] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Affiliation(s)
- Vinh Son Nguyen
- Department of Chemistry, University of Leuven, Leuven, Belgium
| | | | | | | | | |
Collapse
|
23
|
Soorkia S, Liu CL, Savee JD, Ferrell SJ, Leone SR, Wilson KR. Airfoil sampling of a pulsed Laval beam with tunable vacuum ultraviolet synchrotron ionization quadrupole mass spectrometry: application to low-temperature kinetics and product detection. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2011; 82:124102. [PMID: 22225233 DOI: 10.1063/1.3669537] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
A new pulsed Laval nozzle apparatus with vacuum ultraviolet (VUV) synchrotron photoionization quadrupole mass spectrometry is constructed to study low-temperature radical-neutral chemical reactions of importance for modeling the atmosphere of Titan and the outer planets. A design for the sampling geometry of a pulsed Laval nozzle expansion has been developed that operates successfully for the determination of rate coefficients by time-resolved mass spectrometry. The new concept employs airfoil sampling of the collimated expansion with excellent sampling throughput. Time-resolved profiles of the high Mach number gas flow obtained by photoionization signals show that perturbation of the collimated expansion by the airfoil is negligible. The reaction of C(2)H with C(2)H(2) is studied at 70 K as a proof-of-principle result for both low-temperature rate coefficient measurements and product identification based on the photoionization spectrum of the reaction product versus VUV photon energy. This approach can be used to provide new insights into reaction mechanisms occurring at kinetic rates close to the collision-determined limit.
Collapse
Affiliation(s)
- Satchin Soorkia
- Department of Chemistry, University of California, Berkeley, California 94720, USA
| | | | | | | | | | | |
Collapse
|
24
|
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
| |
Collapse
|
25
|
Swinnen S, Elsamra RM, Nguyen VS, Peeters J, Carl SA, Nguyen MT. Theoretical and experimental investigation of the C2H+SO2 reaction over the range T=295–800K. Chem Phys Lett 2011. [DOI: 10.1016/j.cplett.2011.07.098] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
26
|
Jamal A, Mebel AM. Reactions of C2H with 1- and 2-Butynes: An Ab Initio/RRKM Study of the Reaction Mechanism and Product Branching Ratios. J Phys Chem A 2011; 115:2196-207. [DOI: 10.1021/jp111521j] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Affiliation(s)
- Adeel Jamal
- Department of Chemistry and Biochemistry, Florida International University, Florida, 33199, United States
| | - Alexander M. Mebel
- Department of Chemistry and Biochemistry, Florida International University, Florida, 33199, United States
| |
Collapse
|
27
|
Mandal D, Mondal B, Das AK. The association reaction between C2H and 1-butyne: a computational chemical kinetics study. Phys Chem Chem Phys 2011; 13:4583-95. [DOI: 10.1039/c0cp02368j] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
|
28
|
Goulay F, Soorkia S, Meloni G, Osborn DL, Taatjes CA, Leone SR. Detection of pentatetraene by reaction of the ethynyl radical (C2H) with allene (CH2CCH2) at room temperature. Phys Chem Chem Phys 2011; 13:20820-7. [DOI: 10.1039/c1cp22609f] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
29
|
Cataldo F, Ravagnan L, Cinquanta E, Castelli IE, Manini N, Onida G, Milani P. Synthesis, Characterization, and Modeling of Naphthyl-Terminated sp Carbon Chains: Dinaphthylpolyynes. J Phys Chem B 2010; 114:14834-41. [DOI: 10.1021/jp104863v] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Franco Cataldo
- Actinium Chemical Research, Via Casilina 1626/A, I-00133 Rome, Italy, Istituto Nazionale di Astrofisica. Osservatorio Astrofisica di Catania, Via S. Sofia 78, I-95123 Catania, Italy, Dipartimento di Fisica, Università degli Studi di Milano, Via Celoria 16, I-20133 Milano, Italy, CIMAINA, Via Celoria 16, I-20133 Milano, Italy, Dipartimento di Scienza dei Materiali, Università degli Studi di Milano Bicocca, Via Cozzi 53, I-20125 Milano, Italy, and European Theoretical Spectroscopy Facility (ETSF), Via
| | - Luca Ravagnan
- Actinium Chemical Research, Via Casilina 1626/A, I-00133 Rome, Italy, Istituto Nazionale di Astrofisica. Osservatorio Astrofisica di Catania, Via S. Sofia 78, I-95123 Catania, Italy, Dipartimento di Fisica, Università degli Studi di Milano, Via Celoria 16, I-20133 Milano, Italy, CIMAINA, Via Celoria 16, I-20133 Milano, Italy, Dipartimento di Scienza dei Materiali, Università degli Studi di Milano Bicocca, Via Cozzi 53, I-20125 Milano, Italy, and European Theoretical Spectroscopy Facility (ETSF), Via
| | - Eugenio Cinquanta
- Actinium Chemical Research, Via Casilina 1626/A, I-00133 Rome, Italy, Istituto Nazionale di Astrofisica. Osservatorio Astrofisica di Catania, Via S. Sofia 78, I-95123 Catania, Italy, Dipartimento di Fisica, Università degli Studi di Milano, Via Celoria 16, I-20133 Milano, Italy, CIMAINA, Via Celoria 16, I-20133 Milano, Italy, Dipartimento di Scienza dei Materiali, Università degli Studi di Milano Bicocca, Via Cozzi 53, I-20125 Milano, Italy, and European Theoretical Spectroscopy Facility (ETSF), Via
| | - Ivano Eligio Castelli
- Actinium Chemical Research, Via Casilina 1626/A, I-00133 Rome, Italy, Istituto Nazionale di Astrofisica. Osservatorio Astrofisica di Catania, Via S. Sofia 78, I-95123 Catania, Italy, Dipartimento di Fisica, Università degli Studi di Milano, Via Celoria 16, I-20133 Milano, Italy, CIMAINA, Via Celoria 16, I-20133 Milano, Italy, Dipartimento di Scienza dei Materiali, Università degli Studi di Milano Bicocca, Via Cozzi 53, I-20125 Milano, Italy, and European Theoretical Spectroscopy Facility (ETSF), Via
| | - Nicola Manini
- Actinium Chemical Research, Via Casilina 1626/A, I-00133 Rome, Italy, Istituto Nazionale di Astrofisica. Osservatorio Astrofisica di Catania, Via S. Sofia 78, I-95123 Catania, Italy, Dipartimento di Fisica, Università degli Studi di Milano, Via Celoria 16, I-20133 Milano, Italy, CIMAINA, Via Celoria 16, I-20133 Milano, Italy, Dipartimento di Scienza dei Materiali, Università degli Studi di Milano Bicocca, Via Cozzi 53, I-20125 Milano, Italy, and European Theoretical Spectroscopy Facility (ETSF), Via
| | - Giovanni Onida
- Actinium Chemical Research, Via Casilina 1626/A, I-00133 Rome, Italy, Istituto Nazionale di Astrofisica. Osservatorio Astrofisica di Catania, Via S. Sofia 78, I-95123 Catania, Italy, Dipartimento di Fisica, Università degli Studi di Milano, Via Celoria 16, I-20133 Milano, Italy, CIMAINA, Via Celoria 16, I-20133 Milano, Italy, Dipartimento di Scienza dei Materiali, Università degli Studi di Milano Bicocca, Via Cozzi 53, I-20125 Milano, Italy, and European Theoretical Spectroscopy Facility (ETSF), Via
| | - Paolo Milani
- Actinium Chemical Research, Via Casilina 1626/A, I-00133 Rome, Italy, Istituto Nazionale di Astrofisica. Osservatorio Astrofisica di Catania, Via S. Sofia 78, I-95123 Catania, Italy, Dipartimento di Fisica, Università degli Studi di Milano, Via Celoria 16, I-20133 Milano, Italy, CIMAINA, Via Celoria 16, I-20133 Milano, Italy, Dipartimento di Scienza dei Materiali, Università degli Studi di Milano Bicocca, Via Cozzi 53, I-20125 Milano, Italy, and European Theoretical Spectroscopy Facility (ETSF), Via
| |
Collapse
|
30
|
Zins EL, Schröder D. Carbon−Carbon Coupling Reactions of Medium-Sized Nitrogen-Containing Dications. J Phys Chem A 2010; 114:5989-96. [DOI: 10.1021/jp100852q] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Emilie-Laure Zins
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo náměstí 2, 16610 Prague 6, Czech Republic
| | - Detlef Schröder
- Institute of Organic Chemistry and Biochemistry, Academy of Sciences of the Czech Republic, Flemingovo náměstí 2, 16610 Prague 6, Czech Republic
| |
Collapse
|
31
|
Leone SR, Ahmed M, Wilson KR. Chemical dynamics, molecular energetics, and kinetics at the synchrotron. Phys Chem Chem Phys 2010; 12:6564-78. [PMID: 20419177 DOI: 10.1039/c001707h] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Scientists at the Chemical Dynamics Beamline of the Advanced Light Source in Berkeley are continuously reinventing synchrotron investigations of physical chemistry and chemical physics with vacuum ultraviolet light. One of the unique aspects of a synchrotron for chemical physics research is the widely tunable vacuum ultraviolet light that permits threshold ionization of large molecules with minimal fragmentation. This provides novel opportunities to assess molecular energetics and reaction mechanisms, even beyond simple gas phase molecules. In this perspective, significant new directions utilizing the capabilities at the Chemical Dynamics Beamline are presented, along with an outlook for future synchrotron and free electron laser science in chemical dynamics. Among the established and emerging fields of investigations are cluster and biological molecule spectroscopy and structure, combustion flame chemistry mechanisms, radical kinetics and product isomer dynamics, aerosol heterogeneous chemistry, planetary and interstellar chemistry, and secondary neutral ion-beam desorption imaging of biological matter and materials chemistry.
Collapse
Affiliation(s)
- Stephen R Leone
- Department of Chemistry, University of California, Berkeley, CA 94720, USA.
| | | | | |
Collapse
|
32
|
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]
|
33
|
Soorkia S, Trevitt AJ, Selby TM, Osborn DL, Taatjes CA, Wilson KR, Leone SR. Reaction of the C2H Radical with 1-Butyne (C4H6): Low-Temperature Kinetics and Isomer-Specific Product Detection. J Phys Chem A 2010; 114:3340-54. [DOI: 10.1021/jp911132r] [Citation(s) in RCA: 53] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Satchin Soorkia
- Departments of Chemistry and Physics, University of California, Berkeley, California 94720
| | - Adam J. Trevitt
- School of Chemistry, University of Wollongong, Wollongong, New South Wales 2522, Australia
| | - Talitha M. Selby
- Department of Chemistry, University of Wisconsin—Washington County, West Bend, Wisconsin 53095
| | - David L. Osborn
- Combustion Research Facility, Mail Stop 9055, Sandia National Laboratories, Livermore, California 94551-0969
| | - Craig A. Taatjes
- Combustion Research Facility, Mail Stop 9055, Sandia National Laboratories, Livermore, California 94551-0969
| | - Kevin R. Wilson
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720
| | - Stephen R. Leone
- Departments of Chemistry and Physics, University of California, Berkeley, California 94720 and Chemical Sciences Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, California 94720
| |
Collapse
|
34
|
Soorkia S, Taatjes CA, Osborn DL, Selby TM, Trevitt AJ, Wilson KR, Leone SR. Direct detection of pyridine formation by the reaction of CH (CD) with pyrrole: a ring expansion reaction. Phys Chem Chem Phys 2010; 12:8750-8. [DOI: 10.1039/c002135k] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
35
|
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]
|
36
|
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]
|
37
|
Kaiser RI, Maksyutenko P, Ennis C, Zhang F, Gu X, Krishtal SP, Mebel AM, Kostko O, Ahmed M. Untangling the chemical evolution of Titan's atmosphere and surface–from homogeneous to heterogeneous chemistry. Faraday Discuss 2010; 147:429-78; discussion 527-52. [DOI: 10.1039/c003599h] [Citation(s) in RCA: 109] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
38
|
Jamal A, Mebel AM. An ab initio/RRKM study of the reaction mechanism and product branching ratios of the reactions of ethynyl radical with allene and methylacetylene. Phys Chem Chem Phys 2010; 12:2606-18. [DOI: 10.1039/b920977h] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
|
39
|
Greenwald EE, Ghosh B, Anderson KC, Dooley KS, Zou P, Selby T, Osborn DL, Meloni G, Taatjes CA, Goulay F, North SW. Isomer-Selective Study of the OH Initiated Oxidation of Isoprene in the Presence of O2 and NO. I. The Minor Inner OH-Addition Channel. J Phys Chem A 2009; 114:904-12. [DOI: 10.1021/jp908543a] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Erin E. Greenwald
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842, Combustion Research Facility, Mail Stop 9055, Sandia National Laboratories, Livermore, California 94551-0969, Department of Chemistry, University of San Francisco, 2130 Fulton Street, San Francisco, California 94117, and Department of Chemistry, University of California, Berkeley, Berkeley, California 94720
| | - Buddhadeb Ghosh
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842, Combustion Research Facility, Mail Stop 9055, Sandia National Laboratories, Livermore, California 94551-0969, Department of Chemistry, University of San Francisco, 2130 Fulton Street, San Francisco, California 94117, and Department of Chemistry, University of California, Berkeley, Berkeley, California 94720
| | - Katie C. Anderson
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842, Combustion Research Facility, Mail Stop 9055, Sandia National Laboratories, Livermore, California 94551-0969, Department of Chemistry, University of San Francisco, 2130 Fulton Street, San Francisco, California 94117, and Department of Chemistry, University of California, Berkeley, Berkeley, California 94720
| | - Kristin S. Dooley
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842, Combustion Research Facility, Mail Stop 9055, Sandia National Laboratories, Livermore, California 94551-0969, Department of Chemistry, University of San Francisco, 2130 Fulton Street, San Francisco, California 94117, and Department of Chemistry, University of California, Berkeley, Berkeley, California 94720
| | - Peng Zou
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842, Combustion Research Facility, Mail Stop 9055, Sandia National Laboratories, Livermore, California 94551-0969, Department of Chemistry, University of San Francisco, 2130 Fulton Street, San Francisco, California 94117, and Department of Chemistry, University of California, Berkeley, Berkeley, California 94720
| | - Talitha Selby
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842, Combustion Research Facility, Mail Stop 9055, Sandia National Laboratories, Livermore, California 94551-0969, Department of Chemistry, University of San Francisco, 2130 Fulton Street, San Francisco, California 94117, and Department of Chemistry, University of California, Berkeley, Berkeley, California 94720
| | - David L. Osborn
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842, Combustion Research Facility, Mail Stop 9055, Sandia National Laboratories, Livermore, California 94551-0969, Department of Chemistry, University of San Francisco, 2130 Fulton Street, San Francisco, California 94117, and Department of Chemistry, University of California, Berkeley, Berkeley, California 94720
| | - Giovanni Meloni
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842, Combustion Research Facility, Mail Stop 9055, Sandia National Laboratories, Livermore, California 94551-0969, Department of Chemistry, University of San Francisco, 2130 Fulton Street, San Francisco, California 94117, and Department of Chemistry, University of California, Berkeley, Berkeley, California 94720
| | - Craig A. Taatjes
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842, Combustion Research Facility, Mail Stop 9055, Sandia National Laboratories, Livermore, California 94551-0969, Department of Chemistry, University of San Francisco, 2130 Fulton Street, San Francisco, California 94117, and Department of Chemistry, University of California, Berkeley, Berkeley, California 94720
| | - Fabien Goulay
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842, Combustion Research Facility, Mail Stop 9055, Sandia National Laboratories, Livermore, California 94551-0969, Department of Chemistry, University of San Francisco, 2130 Fulton Street, San Francisco, California 94117, and Department of Chemistry, University of California, Berkeley, Berkeley, California 94720
| | - Simon W. North
- Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842, Combustion Research Facility, Mail Stop 9055, Sandia National Laboratories, Livermore, California 94551-0969, Department of Chemistry, University of San Francisco, 2130 Fulton Street, San Francisco, California 94117, and Department of Chemistry, University of California, Berkeley, Berkeley, California 94720
| |
Collapse
|
40
|
Faure A, Vuitton V, Thissen R, Wiesenfeld L. A Semiempirical Capture Model for Fast Neutral Reactions at Low Temperature. J Phys Chem A 2009; 113:13694-9. [DOI: 10.1021/jp905609x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Alexandre Faure
- Laboratoire de Planétologie, Observatoire de Grenoble, Université Joseph Fourier, CNRS UMR5109, B.P. 53, 38041 Grenoble Cedex 09, France, and Laboratoire d’Astrophysique, Observatoire de Grenoble, Université Joseph Fourier, CNRS UMR5571, B.P. 53, 38041 Grenoble Cedex 09, France
| | - Véronique Vuitton
- Laboratoire de Planétologie, Observatoire de Grenoble, Université Joseph Fourier, CNRS UMR5109, B.P. 53, 38041 Grenoble Cedex 09, France, and Laboratoire d’Astrophysique, Observatoire de Grenoble, Université Joseph Fourier, CNRS UMR5571, B.P. 53, 38041 Grenoble Cedex 09, France
| | - Roland Thissen
- Laboratoire de Planétologie, Observatoire de Grenoble, Université Joseph Fourier, CNRS UMR5109, B.P. 53, 38041 Grenoble Cedex 09, France, and Laboratoire d’Astrophysique, Observatoire de Grenoble, Université Joseph Fourier, CNRS UMR5571, B.P. 53, 38041 Grenoble Cedex 09, France
| | - Laurent Wiesenfeld
- Laboratoire de Planétologie, Observatoire de Grenoble, Université Joseph Fourier, CNRS UMR5109, B.P. 53, 38041 Grenoble Cedex 09, France, and Laboratoire d’Astrophysique, Observatoire de Grenoble, Université Joseph Fourier, CNRS UMR5571, B.P. 53, 38041 Grenoble Cedex 09, France
| |
Collapse
|
41
|
Zhang F, Kim S, Kaiser RI. A crossed molecular beams study of the reaction of the ethynyl radical (C2H(X2Sigma+)) with allene (H2CCCH2(X1A1)). Phys Chem Chem Phys 2009; 11:4707-14. [PMID: 19492123 DOI: 10.1039/b822366a] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The crossed beams reaction of ground state ethynyl radicals, C(2)H(X(2)Sigma(+)), with allene, H(2)CCCH(2)(X(1)A(1)), was conducted under single collision conditions at a collision energy of 22.0 +/- 0.4 kJ mol(-1). The center-of-mass functions were combined with earlier ab initio calculations and revealed that the reaction was barrier-less, proceeded via indirect reaction dynamics through an addition of the ethynyl radical to the terminal carbon atom of the allene molecule, and was terminated by atomic hydrogen emission via a tight exit transition state to form the ethynylallene product. The overall reaction was found to be exoergic by 93 +/- 15 kJ mol(-1). Since the reaction is barrier-less, exoergic, and all transition states involved are located below the energy level of the separated reactants, the formation of ethynylallene is predicted to take place in low temperature atmospheres of planets and their satellites such as Titan and also in cold molecular clouds via the neutral-neutral reaction of ethynyl radicals with allene. Implications to interstellar chemistry and a comparison with the chemistry of the isoelectronic cyano radical, CN(X(2)Sigma(+)), are also presented.
Collapse
Affiliation(s)
- Fangtong Zhang
- Department of Chemistry, University of Hawai'i at Manoa, Honolulu, HI 96822, USA
| | | | | |
Collapse
|
42
|
Simmonett AC, Schaefer HF, Allen WD. Enthalpy of formation and anharmonic force field of diacetylene. J Chem Phys 2009; 130:044301. [DOI: 10.1063/1.3054917] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
|
43
|
Ismail H, Abel PR, Green WH, Fahr A, Jusinski LE, Knepp AM, Zádor J, Meloni G, Selby TM, Osborn DL, Taatjes CA. Temperature-Dependent Kinetics of the Vinyl Radical (C2H3) Self-Reaction. J Phys Chem A 2009; 113:1278-86. [DOI: 10.1021/jp8096132] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Huzeifa Ismail
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139
| | | | | | - Askar Fahr
- Department of Chemistry, Howard University, Washington, D.C. 20059
| | | | | | | | | | | | | | | |
Collapse
|
44
|
Goulay F, Trevitt AJ, Meloni G, Selby TM, Osborn DL, Taatjes CA, Vereecken L, Leone SR. Cyclic Versus Linear Isomers Produced by Reaction of the Methylidyne Radical (CH) with Small Unsaturated Hydrocarbons. J Am Chem Soc 2009; 131:993-1005. [DOI: 10.1021/ja804200v] [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)
- Fabien Goulay
- Ernest Orlando Lawrence Berkeley National Laboratory, Berkeley, California 94720, Departments of Chemistry and Physics, University of California, Berkeley, California 94720, Combustion Research Facility, Mail Stop 9055, Sandia National Laboratories, Livermore, California 94551-0969, and Department of Chemistry, K. U. Leuven, Celestijnenlaan 200F, B-3001 Leuven, Belgium
| | - Adam J. Trevitt
- Ernest Orlando Lawrence Berkeley National Laboratory, Berkeley, California 94720, Departments of Chemistry and Physics, University of California, Berkeley, California 94720, Combustion Research Facility, Mail Stop 9055, Sandia National Laboratories, Livermore, California 94551-0969, and Department of Chemistry, K. U. Leuven, Celestijnenlaan 200F, B-3001 Leuven, Belgium
| | - Giovanni Meloni
- Ernest Orlando Lawrence Berkeley National Laboratory, Berkeley, California 94720, Departments of Chemistry and Physics, University of California, Berkeley, California 94720, Combustion Research Facility, Mail Stop 9055, Sandia National Laboratories, Livermore, California 94551-0969, and Department of Chemistry, K. U. Leuven, Celestijnenlaan 200F, B-3001 Leuven, Belgium
| | - Talitha M. Selby
- Ernest Orlando Lawrence Berkeley National Laboratory, Berkeley, California 94720, Departments of Chemistry and Physics, University of California, Berkeley, California 94720, Combustion Research Facility, Mail Stop 9055, Sandia National Laboratories, Livermore, California 94551-0969, and Department of Chemistry, K. U. Leuven, Celestijnenlaan 200F, B-3001 Leuven, Belgium
| | - David L. Osborn
- Ernest Orlando Lawrence Berkeley National Laboratory, Berkeley, California 94720, Departments of Chemistry and Physics, University of California, Berkeley, California 94720, Combustion Research Facility, Mail Stop 9055, Sandia National Laboratories, Livermore, California 94551-0969, and Department of Chemistry, K. U. Leuven, Celestijnenlaan 200F, B-3001 Leuven, Belgium
| | - Craig A. Taatjes
- Ernest Orlando Lawrence Berkeley National Laboratory, Berkeley, California 94720, Departments of Chemistry and Physics, University of California, Berkeley, California 94720, Combustion Research Facility, Mail Stop 9055, Sandia National Laboratories, Livermore, California 94551-0969, and Department of Chemistry, K. U. Leuven, Celestijnenlaan 200F, B-3001 Leuven, Belgium
| | - Luc Vereecken
- Ernest Orlando Lawrence Berkeley National Laboratory, Berkeley, California 94720, Departments of Chemistry and Physics, University of California, Berkeley, California 94720, Combustion Research Facility, Mail Stop 9055, Sandia National Laboratories, Livermore, California 94551-0969, and Department of Chemistry, K. U. Leuven, Celestijnenlaan 200F, B-3001 Leuven, Belgium
| | - Stephen R. Leone
- Ernest Orlando Lawrence Berkeley National Laboratory, Berkeley, California 94720, Departments of Chemistry and Physics, University of California, Berkeley, California 94720, Combustion Research Facility, Mail Stop 9055, Sandia National Laboratories, Livermore, California 94551-0969, and Department of Chemistry, K. U. Leuven, Celestijnenlaan 200F, B-3001 Leuven, Belgium
| |
Collapse
|
45
|
Indarto A, Giordana A, Ghigo G, Tonachini G. Formation of PAHs and soot platelets: multiconfiguration theoretical study of the key step in the ring closure-radical breeding polyyne-based mechanism. J PHYS ORG CHEM 2009. [DOI: 10.1002/poc.1613] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
46
|
Casavecchia P, Leonori F, Balucani N, Petrucci R, Capozza G, Segoloni E. Probing the dynamics of polyatomic multichannel elementary reactions by crossed molecular beam experiments with soft electron-ionization mass spectrometric detection. Phys Chem Chem Phys 2008; 11:46-65. [PMID: 19081908 DOI: 10.1039/b814709d] [Citation(s) in RCA: 88] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In this Perspective we highlight developments in the field of chemical reaction dynamics. Focus is on the advances recently made in the investigation of the dynamics of elementary multichannel radical-molecule and radical-radical reactions, as they have become possible using an improved crossed molecular beam scattering apparatus with universal electron-ionization mass spectrometric detection and time-of-flight analysis. These improvements consist in the implementation of (a) soft ionization detection by tunable low-energy electrons which has permitted us to reduce interfering signals originating from dissociative ionization processes, usually representing a major complication, (b) different beam crossing-angle set-ups which have permitted us to extend the range of collision energies over which a reaction can be studied, from very low (a few kJ mol(-1), as of interest in astrochemistry or planetary atmospheric chemistry) to quite high energies (several tens of kJ mol(-1), as of interest in high temperature combustion systems), and (c) continuous supersonic sources for producing a wide variety of atomic and molecular radical reactant beams. Exploiting these new features it has become possible to tackle the dynamics of a variety of polyatomic multichannel reactions, such as those occurring in many environments ranging from combustion and plasmas to terrestrial/planetary atmospheres and interstellar clouds. By measuring product angular and velocity distributions, after having suppressed or mitigated, when needed, the problem of dissociative ionization of interfering species (reactants, products, background gases) by soft ionization detection, essentially all primary reaction products can be identified, the dynamics of each reaction channel characterized, and the branching ratios determined as a function of collision energy. In general this information, besides being of fundamental relevance, is required for a predictive description of the chemistry of these environments via computer models. Examples are taken from recent on-going work (partly published) on the reactions of atomic oxygen with acetylene, ethylene and allyl radical, of great importance in combustion. A reaction of relevance in interstellar chemistry, as that of atomic carbon with acetylene, is also discussed briefly. Comparison with theoretical results is made wherever possible, both at the level of electronic structure calculations of the potential energy surfaces and dynamical computations. Recent complementary CMB work as well as kinetic work exploiting soft photo-ionization with synchrotron radiation are noted. The examples illustrated in this article demonstrate that the type of dynamical results now obtainable on polyatomic multichannel radical-molecule and radical-radical reactions might well complement reaction kinetics experiments and hence contribute to bridging the gap between microscopic reaction dynamics and thermal reaction kinetics, enhancing significantly our basic knowledge of chemical reactivity and understanding of the elementary reactions which occur in real-world environments.
Collapse
|
47
|
Osborn DL, Zou P, Johnsen H, Hayden CC, Taatjes CA, Knyazev VD, North SW, Peterka DS, Ahmed M, Leone SR. The multiplexed chemical kinetic photoionization mass spectrometer: a new approach to isomer-resolved chemical kinetics. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2008; 79:104103. [PMID: 19044733 DOI: 10.1063/1.3000004] [Citation(s) in RCA: 150] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We have developed a multiplexed time- and photon-energy-resolved photoionization mass spectrometer for the study of the kinetics and isomeric product branching of gas phase, neutral chemical reactions. The instrument utilizes a side-sampled flow tube reactor, continuously tunable synchrotron radiation for photoionization, a multimass double-focusing mass spectrometer with 100% duty cycle, and a time- and position-sensitive detector for single ion counting. This approach enables multiplexed, universal detection of molecules with high sensitivity and selectivity. In addition to measurement of rate coefficients as a function of temperature and pressure, different structural isomers can be distinguished based on their photoionization efficiency curves, providing a more detailed probe of reaction mechanisms. The multiplexed three-dimensional data structure (intensity as a function of molecular mass, reaction time, and photoionization energy) provides insights that might not be available in serial acquisition, as well as additional constraints on data interpretation.
Collapse
Affiliation(s)
- David L Osborn
- Combustion Research Facility, Mail Stop 9055, Sandia National Laboratories, Livermore, California 94551-0969, USA.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
48
|
Selby TM, Meloni G, Goulay F, Leone SR, Fahr A, Taatjes CA, Osborn DL. Synchrotron Photoionization Mass Spectrometry Measurements of Kinetics and Product Formation in the Allyl Radical (H2CCHCH2) Self-Reaction. J Phys Chem A 2008; 112:9366-73. [DOI: 10.1021/jp802330k] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Talitha M. Selby
- Sandia National Laboratories, Combustion Research Facility, MS 9055, Livermore, California 94551-0969, Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, and Department of Chemistry, Howard University, Washington, D.C. 20059
| | - Giovanni Meloni
- Sandia National Laboratories, Combustion Research Facility, MS 9055, Livermore, California 94551-0969, Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, and Department of Chemistry, Howard University, Washington, D.C. 20059
| | - Fabien Goulay
- Sandia National Laboratories, Combustion Research Facility, MS 9055, Livermore, California 94551-0969, Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, and Department of Chemistry, Howard University, Washington, D.C. 20059
| | - Stephen R. Leone
- Sandia National Laboratories, Combustion Research Facility, MS 9055, Livermore, California 94551-0969, Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, and Department of Chemistry, Howard University, Washington, D.C. 20059
| | - Askar Fahr
- Sandia National Laboratories, Combustion Research Facility, MS 9055, Livermore, California 94551-0969, Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, and Department of Chemistry, Howard University, Washington, D.C. 20059
| | - Craig A. Taatjes
- Sandia National Laboratories, Combustion Research Facility, MS 9055, Livermore, California 94551-0969, Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, and Department of Chemistry, Howard University, Washington, D.C. 20059
| | - David L. Osborn
- Sandia National Laboratories, Combustion Research Facility, MS 9055, Livermore, California 94551-0969, Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, and Department of Chemistry, Howard University, Washington, D.C. 20059
| |
Collapse
|
49
|
Taatjes CA, Osborn DL, Selby TM, Meloni G, Fan H, Pratt ST. Absolute photoionization cross-section of the methyl radical. J Phys Chem A 2008; 112:9336-43. [PMID: 18572896 DOI: 10.1021/jp8022937] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
The absolute photoionization cross-section of the methyl radical has been measured using two completely independent methods. The CH3 photoionization cross-section was determined relative to that of acetone and methyl vinyl ketone at photon energies of 10.2 and 11.0 eV by using a pulsed laser-photolysis/time-resolved synchrotron photoionization mass spectrometry method. The time-resolved depletion of the acetone or methyl vinyl ketone precursor and the production of methyl radicals following 193 nm photolysis are monitored simultaneously by using time-resolved synchrotron photoionization mass spectrometry. Comparison of the initial methyl signal with the decrease in precursor signal, in combination with previously measured absolute photoionization cross-sections of the precursors, yields the absolute photoionization cross-section of the methyl radical; sigma(CH3)(10.2 eV) = (5.7 +/- 0.9) x 10(-18) cm(2) and sigma(CH3)(11.0 eV) = (6.0 +/- 2.0) x 10(-18) cm(2). The photoionization cross-section for vinyl radical determined by photolysis of methyl vinyl ketone is in good agreement with previous measurements. The methyl radical photoionization cross-section was also independently measured relative to that of the iodine atom by comparison of ionization signals from CH3 and I fragments following 266 nm photolysis of methyl iodide in a molecular-beam ion-imaging apparatus. These measurements gave a cross-section of (5.4 +/- 2.0) x 10(-18) cm(2) at 10.460 eV, (5.5 +/- 2.0) x 10(-18) cm(2) at 10.466 eV, and (4.9 +/- 2.0) x 10(-18) cm(2) at 10.471 eV. The measurements allow relative photoionization efficiency spectra of methyl radical to be placed on an absolute scale and will facilitate quantitative measurements of methyl concentrations by photoionization mass spectrometry.
Collapse
Affiliation(s)
- Craig A Taatjes
- Combustion Research Facility, Mail Stop 9055, Sandia National Laboratories, Livermore, California 94551-0969, USA.
| | | | | | | | | | | |
Collapse
|
50
|
Ricketts C, Schröder D, Alcaraz C, Roithová J. Growth of Larger Hydrocarbons in the Ionosphere of Titan. Chemistry 2008; 14:4779-83. [DOI: 10.1002/chem.200800524] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|