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Title: A combined crossed molecular beams and computational study on the formation of distinct resonantly stabilized C5H3 radicals via chemically activated C5H4 and C6H6 intermediates

Journal Article · · Physical Chemistry Chemical Physics. PCCP
DOI:https://doi.org/10.1039/c8cp00357b· OSTI ID:1603058
ORCiD logo [1];  [1];  [1];  [1]; ORCiD logo [1]; ORCiD logo [2]
  1. Univ. of Hawaii at Manoa, Honolulu, HI (United States)
  2. Florida International Univ., Miami, FL (United States)
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The crossed molecular beams technique was utilized to investigate the formation of three isomers of resonantly stabilized (C5H3) radicals along with their d2-substituted counterparts via the bimolecular reactions of singlet/triplet dicarbon [C2(X1Σ+g/a3Πu)] with methylacetylene [CH3CCH(X1A1)], d3-methylacetylene [CD3CCH(X1A1)], and 1-butyne [C2H5CCH(X1A')] at collision energies up to 26 kJ mol-1via chemically activated singlet/triplet C5H4/C5D3H and C6H6 intermediates. These studies exploit a newly developed supersonic dicarbon [C2(X1Σ+g/a3Πu)] beam generated via photolysis of tetrachloroethylene [C2Cl4(X1Ag)] by excluding interference from carbon atoms, which represent the dominating (interfering) species in ablation-based dicarbon sources. We assessed the performance of the dicarbon [C2(X1Σ+g/a3Πu)] beam in reactions with methylacetylene [CH3CCH(X1A1)] and d3-methylacetylene [CD3CCH(X1A1)]; the investigations demonstrate that the reaction dynamics match previous studies in our laboratory utilizing ablation-based dicarbon sources involving the synthesis of 1,4-pentadiynyl-3 [HCCCHCCH(X2B1)] and 2,4-pentadiynyl-1 [H2CCCCCH(X2B1)] radicals via hydrogen (deuterium) atom elimination. Considering the C2(X1Σ+g/a3Πu)–1-butyne [C2H5CCH(X1A')] reaction, the hitherto elusive methyl-loss pathway was detected. This channel forms the previously unknown resonantly stabilized penta-1-yn-3,4-dienyl-1 [H2CCCHCC(X2A)] radical along with the methyl radical [CH3(X2A2")] and is open exclusively on the triplet surface with an overall reaction energy of -86 ± 10 kJ mol-1. The preferred reaction pathways proceed first by barrierless addition of triplet dicarbon to the π-electronic system of 1-butyne, either to both acetylenic carbon atoms or to the sterically more accessible carbon atom, to form the methyl-bearing triplet C6H6 intermediates [i41b] and [i81b], respectively, with the latter decomposing via a tight exit transition state to penta-1-yn-3,4-dienyl-1 [(H2CCCHCC(X2A)] plus the methyl radical [CH3(X2A2")]. The successful unraveling of this methyl-loss channel – through collaborative experimental and computational efforts – underscores the viability of the photolytically generated dicarbon beam as an unprecedented tool to access reaction dynamics underlying the formation of resonantly stabilized free radicals (RSFR) that are vital to molecular mass growth processes that ultimately lead to polycyclic aromatic hydrocarbons (PAHs)

Research Organization:
Univ. of Hawaii, Honolulu, HI (United States); Florida International Univ. (FIU), Miami, FL (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Basic Energy Sciences (BES)
Grant/Contract Number:
FG02-03ER15411; FG02-04ER15570
OSTI ID:
1603058
Alternate ID(s):
OSTI ID: 1434083
Journal Information:
Physical Chemistry Chemical Physics. PCCP, Vol. 20, Issue 16; ISSN 1463-9076
Publisher:
Royal Society of ChemistryCopyright Statement
Country of Publication:
United States
Language:
English
Citation Metrics:
Cited by: 5 works
Citation information provided by
Web of Science

References (116)

Absorption and Emission Measurements of C 2 and CH Electronic Bands in Low‐Pressure Oxyacetylene Flames journal November 1965
High resolution spectroscopy and spectral simulation of C2 using degenerate four-wave mixing journal January 1999
Scavenging of hydrocarbon radicals from flames with dimethyl-disulfide II. Hydrocarbon radicals in fuel-rich low-pressure flames of acetylene, ethylene, 1,3-butadiene and methane with oxygen journal April 1997
High-resolution spectroscopy of the C2 Swan 0-0 band from Comet P/Halley journal April 1990
A Critical Study of Molecular Photodissociation and CHON Grain Sources for Cometary C 2 journal August 1997
Hubble Space Telescope observations of C2 molecules in diffuse interstellar clouds journal January 1995
Chemically activated reactions on the C7H5 energy surface: propargyl + diacetylene, i-C5H3 + acetylene, and n-C5H3 + acetylene journal January 2011
Line formation in solar granulation: VI. [C I], C I, CH and C journal February 2005
The Chemical Composition of the Sun journal September 2009
The extent of mixing in stellar interiors: the open clusters Collinder 261 and Melotte 66 journal April 2016
Spectroscopic observations of CRL 2688 journal June 1975
Mechanism of formation of CH, C2, OH and HCO radicals in flames journal January 1953
C2 Swan band laser-induced fluorescence and chemiluminescence in low-pressure hydrocarbon flames journal April 2005
Quantitative Laser Diagnostic and Modeling Study of C 2 and CH Chemistry in Combustion † journal April 2010
Quadruple bonding in C2 and analogous eight-valence electron species journal January 2012
Resonance-Enhanced 2-Photon Ionization Scheme for C 2 through a Newly Identified Band System: 4 3 Π g – a 3 Π u journal July 2015
Higher vibrational levels of the D 1 Σ u + state of dicarbon: New Mulliken bands journal February 2018
Formation of resonantly stabilised free radicals via the reactions of atomic carbon, dicarbon, and tricarbon with unsaturated hydrocarbons: theory and crossed molecular beams experiments journal October 2015
A Crossed Beam and ab Initio Investigation of the Reaction of Hydrogen Sulfide, H 2 S(X 1 A 1 ), with Dicarbon Molecules, C 2 (X 1 Σ g + ) journal May 2002
A Crossed Molecular Beams Study on the Formation of the Exotic Cyanoethynyl Radical in Titan'S Atmosphere journal August 2009
Crossed molecular beam studies of C( 3 P, 1 D) and C 2 ( X 1 Σ + g , a 3 Π u ) reactions with acetylene journal October 2008
Chemical Dynamics of the Formation of the 1,3-Butadiynyl Radical (C 4 H(X 2 Σ + )) and Its Isotopomers journal October 2006
Mass spectrum of the butadiynyl radical (C4H; X2∑+) journal November 2005
A crossed beam and ab initio study of the C2(X1Σg+ /a3∏u)+C2H2(X1Σg+) reactions journal November 2003
Crossed molecular beam study of gas phase reactions relevant to the chemistry of planetary atmospheres: The case of C2+C2H2 journal November 2008
Formation of the 1,3,5-Hexatriynyl Radical (C 6 H(X 2 Π)) via the Crossed Beams Reaction of Dicarbon (C 2 (X 1 Σ g + /a 3 Π u )), with Diacetylene (C 4 H 2 (X 1 Σ g + )) journal February 2009
Dynamics of the reaction of C 2 with C 6 H 2 : An implication for the formation of interstellar C 8 H journal November 2014
Formation of Polyynes C 4 H 2 , C 6 H 2 , C 8 H 2 , and C 10 H 2 from Reactions of C 2 H, C 4 H, C 6 H, and C 8 H Radicals with C 2 H 2 journal September 2015
Circumstellar acetylene in the infrared spectrum of IRC +10° 216 journal November 1976
Detection of C2 in the interstellar spectrum of Cygnus OB2 number 12 /VI Cygni number 12/ journal August 1977
Detection of the C4H radical toward IRC plus 10216 journal August 1978
Discovery of interstellar acetylene journal July 1989
[ITAL]Infrared Space Observatory's[/ITAL] Discovery of C[TINF]4[/TINF]H[TINF]2[/TINF], C[TINF]6[/TINF]H[TINF]2[/TINF], and Benzene in CRL 618 journal January 2001
Crossed beam reaction of atomic carbon, C(3Pj), with the propargyl radical, C3H3(X 2B2): Observation of diacetylene, C4H2(X 1Σg+) journal November 1997
Chemical dynamics of cyclopropynylidyne (c-C[sub 3]H; X[sup 2]B[sub 2]) formation from the reaction of C([sup 1]D) with acetylene, C[sub 2]H[sub 2](X [sup 1]Σ[sub g][sup +]) journal January 2001
Neutral‐Neutral Reactions in the Interstellar Medium. I. Formation of Carbon Hydride Radicals via Reaction of Carbon Atoms with Unsaturated Hydrocarbons journal March 1997
Crossed-beam reaction of carbon atoms with hydrocarbon molecules. V. Chemical dynamics of n-C4H3 formation from reaction of C(3Pj) with allene, H2CCCH2(X 1A1) journal June 1999
A Combined Crossed Beam and Ab Initio Investigation of the Gas Phase Reaction of Dicarbon Molecules (C 2 ; X 1 Σ g + /a 3 Π u ) with Propene (C 3 H 6 ; X 1 A′): Identification of the Resonantly Stabilized Free Radicals 1- and 3-Vinylpropargyl journal May 2013
A crossed molecular beams study on the formation and energetics of the resonantly stabilized free i-C4H3(X2A′) radical and its isotopomers journal June 2007
Mass spectrum of the 1-butene-3-yne-2-yl radical (i-C4H3; X2A′) journal March 2006
SEARCHING FOR INTERSTELLAR MOLECULE BUTATRIENYLIDENE IN REACTION C 2 + C 2 H 4 journal October 2012
A Crossed Molecular Beams and Ab Initio Study on the Formation of C 6 H 3 Radicals. An Interface between Resonantly Stabilized and Aromatic Radicals journal September 2011
Untangling the chemical evolution of Titan's atmosphere and surface–from homogeneous to heterogeneous chemistry journal January 2010
A crossed molecular beam study on the reaction of methylidyne radicals [CH(X 2 Π)] with acetylene [C 2 H 2 (X 1 Σ g + )]—competing C 3 H 2 + H and C 3 H + H 2 channels journal January 2011
Chemical dynamics of the CH(X 2 Π) + C 2 H 4 (X 1 A 1g ), CH(X 2 Π) + C 2 D 4 (X 1 A 1g ), and CD(X 2 Π) + C 2 H 4 (X 1 A 1g ) reactions studied under single collision conditions journal January 2012
Chemical dynamics of d1-methyldiacetylene (CH3CCCCD; X 1A1) and d1-ethynylallene (H2CCCH(C2D); X 1A′) formation from reaction of C2D(X 2Σ+) with methylacetylene, CH3CCH(X 1A1) journal February 2001
Reaction of the ethynyl radical, C2H, with methylacetylene, CH3CCH, under single collision conditions: Implications for astrochemistry journal February 2001
Formation of benzene in the interstellar medium journal December 2010
Photoinduced Mechanism of Formation and Growth of Polycyclic Aromatic Hydrocarbons in Low-Temperature Environments via Successive Ethynyl Radical Additions journal October 2008
Kinetic modeling study of benzene and PAH formation in laminar methane flames journal May 2015
Toward the Oxidation of the Phenyl Radical and Prevention of PAH Formation in Combustion Systems journal November 2014
Aromatic and Polycyclic Aromatic Hydrocarbon Formation in a Laminar Premixed n-Butane Flame journal July 1998
Can the C 5 H 5 + C 5 H 5 → C 10 H 10 → C 10 H 9 + H/C 10 H 8 + H 2 Reaction Produce Naphthalene? An Ab Initio/RRKM Study journal September 2009
A detailed kinetic modeling study of toluene oxidation in a premixed laminar flame journal January 2011
An experimental study of the premixed benzene/oxygen/argon flame with tunable synchrotron photoionization journal January 2007
Identification of isomeric C5H3 and C5H5 free radicals in flame with tunable synchrotron photoionization journal June 2006
Identification of C 5 H x Isomers in Fuel-Rich Flames by Photoionization Mass Spectrometry and Electronic Structure Calculations journal April 2006
Photodissociation of benzene under collision-free conditions: An ab initio /Rice–Ramsperger–Kassel–Marcus study journal April 2004
Theoretical Study on the Mechanism of the Dissociation of Benzene. The C 5 H 3 + CH 3 Product Channel journal September 1997
Formation of the 2,4-Pentadiynyl-1 Radical (H 2 CCCCCH, X 2 B 1 ) in the Crossed Beams Reaction of Dicarbon Molecules with Methylacetylene journal May 2006
Unimolecular Decomposition of Chemically Activated Pentatetraene (H 2 CCCCCH 2 ) Intermediates:  A Crossed Beams Study of Dicarbon Molecule Reactions with Allene journal September 2006
Understanding the chemical dynamics of the reactions of dicarbon with 1-butyne, 2-butyne, and 1,2-butadiene – toward the formation of resonantly stabilized free radicals journal January 2014
A Combined Crossed Molecular Beam and ab Initio Study of the Reactions C 2 (X 1 ∑ g + , a 3 Π u ) + C 2 H 4 → n -C 4 H 3 (X 2 A‘) + H( 2 S 1/2 ) journal November 2001
A Combined Experimental and Theoretical Study of the Reaction of Dicarbon (C 2 ) with D1‐Acetylene (HCCD): Possible Mechanisms for Deuterium Enrichment in the Interstellar D1‐Butadiynyl Radical, CCCCD( X 2 Σ + ) journal December 2006
Ab Initio MO Study of the Global Potential Energy Surface of C 4 H 4 in Triplet Electronic State and the Reactions of C( 3 P j ) with C 3 H 4 (Allene and Propyne) and C 2 (A 3 Π u ) with C 2 H 4 (X 1 A 1g + ) journal March 2000
An experimental and theoretical investigation of the formation of C7H7 isomers in the bimolecular reaction of dicarbon molecules with 1,3-pentadiene journal June 2014
Gas-Phase Synthesis of the Benzyl Radical (C 6 H 5 CH 2 ) journal March 2014
A crossed molecular beams study of the reaction of dicarbon molecules with benzene journal February 2007
Formation of the Phenyl Radical [C 6 H 5 (X 2 A 1 )] under Single Collision Conditions: A Crossed Molecular Beam and ab Initio Study journal March 2010
Characteristics and diagnostics of an ultrahigh vacuum compatible laser ablation source for crossed molecular beam experiments journal May 2006
Crossed beam reaction of cyano radicals with hydrocarbon molecules. II. Chemical dynamics of 1-cyano-1-methylallene (CNCH3CCCH2; X 1A′) formation from reaction of CN(X 2Σ+) with dimethylacetylene CH3CCCH3 (X 1A1′) journal October 1999
Crossed beam reaction of the cyanogen radical, CN(X 2Σ+), with acetylene, C2H2(X 1Σg+): Observation of cyanoacetylene, HCCCN(X 1Σ+) journal April 1999
Crossed beam reaction of the cyano radical, CN(X  2Σ+), with methylacetylene, CH3CCH (X  1A1): Observation of cyanopropyne, CH3CCCN (X  1A1), and cyanoallene, H2CCCHCN (X  1A′) journal August 1999
Formation of Three C 4 H 3 N Isomers from the Reaction of CN (X 2 Σ + ) with Allene, H 2 CCCH 2 (X 1 A 1 ), and Methylacetylene, CH 3 CCH (X 1 A 1 ):  A Combined Crossed Beam and Ab Initio Study journal May 2002
A versatile source to produce high-intensity, pulsed supersonic radical beams for crossed-beam experiments: The cyanogen radical CN(X2Σ+) as a case study journal November 1999
Crossed beams reaction of atomic carbon, C(3Pj), with d6-benzene, C6D6(X 1A1g): Observation of the per-deutero-1,2-didehydro- cycloheptatrienyl radical, C7D5(X 2B2) journal April 1999
A combined crossed beam and ab initio investigation on the reaction of carbon species with C4H6 isomers. I. The 1,3-butadiene molecule, H2CCHCHCH2(X1A′) journal December 2000
A combined crossed beam and ab initio investigation on the reaction of carbon species with C4H6 isomers. II. The dimethylacetylene molecule, H3CCCCH3(X1A1g) journal December 2000
A combined crossed beam and ab initio investigation on the reaction of carbon species with C4H6 isomers. III. 1,2-butadiene, H2CCCH(CH3) (X 1A′)—a non-Rice–Ramsperger–Kassel–Marcus system? journal September 2001
CO Chemiluminescence and Kinetics of the C 2 + O 2 Reaction journal April 2001
Wide-Temperature Range Kinetics and CN(B−X) Violet Chemiluminescence of the C 2 (a 3 Π) + NO Reaction † journal September 2002
Kinetics of C2 (a3Πu) reactions with sulfur containing molecules journal May 2004
The Kinetics of the Reactions of C 2 (a 3 Π u ) with Alcohols journal May 2005
Mechanism and Kinetic Isotope Effect of the Reaction of C 2 (X 1 Σ g + ) Radicals with H 2 and D 2 journal August 2009
Rate Constants and Kinetic Isotope Effects on the Reaction of C 2 (X 1 Σ g + ) with CH 4 and CD 4 journal April 2010
Kinetics of C2(a3Πu) radical reactions with alkanes by LIF journal February 2004
Rate Coefficients for the Reactions of C 2 (a 3 Π u ) and C 2 (X 1 Σ g + ) with Various Hydrocarbons (CH 4 , C 2 H 2 , C 2 H 4 , C 2 H 6 , and C 3 H 8 ): A Gas-Phase Experimental Study over the Temperature Range 24−300 K † journal October 2008
A high‐intensity, pulsed supersonic carbon source with C( 3 P j ) kinetic energies of 0.08–0.7 eV for crossed beam experiments journal December 1995
Development of a stable source of atomic oxygen with a pulsed high-voltage discharge and its application to crossed-beam reactions journal August 2007
Magnetic Analysis of Supersonic Beams of Atomic Oxygen, Nitrogen, and Chlorine Generated from a Radio-Frequency Discharge journal January 1997
Reaction dynamics of carbon-bearing radicals in circumstellar envelopes of carbon stars journal January 2006
Potential Energy Surface and Product Branching Ratios for the Reaction of Dicarbon, C 2 (X 1 Σ g + ), with Methylacetylene, CH 3 CCH(X 1 A 1 ):  An Ab Initio/RRKM Study journal February 2006
Unimolecular decomposition of chemically activated singlet and triplet D3-methyldiacetylene molecules journal August 2007
Electron Bombardment Molecular Beam Detector journal July 1966
Scintillation Type Mass Spectrometer Ion Detector journal March 1960
A high‐intensity multi‐purpose piezoelectric pulsed molecular beam source journal April 1989
Crossed-beam universal-detection reactive scattering of radical beams characterized by laser-induced-fluorescence: the case of C 2 and CN journal April 2010
Simultaneous analysis of the Ballik-Ramsay and Phillips systems of C 2 and observation of forbidden transitions between singlet and triplet states journal February 2015
Oscillator strengths of the Mulliken, Swan, Ballik-Ramsay, Phillips, and dΠg3←cΣu+3 systems of C2 calculated by MRCI methods utilizing a biorthogonal transformation of CASSCF orbitals journal December 2007
PGOPHER: A program for simulating rotational, vibrational and electronic spectra journal January 2017
Line strengths and updated molecular constants for the C2 Swan system journal July 2013
Combined Experimental and Theoretical Study on the Formation of the Elusive 2-Methyl-1-silacycloprop-2-enylidene Molecule under Single Collision Conditions via Reactions of the Silylidyne Radical (SiH; X 2 Π) with Allene (H 2 CCCH 2 ; X 1 A 1 ) and D4-Allene (D 2 CCCD 2 ; X 1 A 1 ) journal November 2015
Density‐functional thermochemistry. III. The role of exact exchange journal April 1993
A full coupled‐cluster singles and doubles model: The inclusion of disconnected triples journal February 1982
Gaussian basis sets for use in correlated molecular calculations. I. The atoms boron through neon and hydrogen journal January 1989
Basis set and correlation dependent extrapolation of correlation energy journal February 2003
A simple and efficient CCSD(T)-F12 approximation journal December 2007
Simplified CCSD(T)-F12 methods: Theory and benchmarks journal February 2009
On the Competition between Linear and Cyclic Isomers in Second-Row Dicarbides journal November 2004
Formation of 6-Methyl-1,4-dihydronaphthalene in the Reaction of the p -Tolyl Radical with 1,3-Butadiene under Single-Collision Conditions journal October 2014
Molecular Reaction Dynamics book January 2005
Crossed beam study of the atom-radical reaction of ground state carbon atoms (C( 3 P)) with the vinyl radical (C 2 H 3 (X 2 A′)) journal January 2012
Line formation in solar granulation: IV. [O I], O I and OH lines and the photospheric O abundance journal March 2004
On the Competition Between Linear and Cyclic Isomers in Second-Row Dicarbides journal January 2005
Development of the Colle-Salvetti correlation-energy formula into a functional of the electron density text January 1988
Line formation in solar granulation: IV. [O I], O I and OH lines and the photospheric O abundance journal April 2005

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