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Title: Mechanisms and time-resolved dynamics for trihydrogen cation (H 3 +) formation from organic molecules in strong laser fields

Abstract

Strong-field laser-matter interactions often lead to exotic chemical reactions. Trihydrogen cation formation from organic molecules is one such case that requires multiple bonds to break and form. Here, we present evidence for the existence of two different reaction pathways for H 3 + formation from organic molecules irradiated by a strong-field laser. Assignment of the two pathways was accomplished through analysis of femtosecond time-resolved strong-field ionization and photoion-photoion coincidence measurements carried out on methanol isotopomers, ethylene glycol, and acetone. Ab initio molecular dynamics simulations suggest the formation occurs via two steps: the initial formation of a neutral hydrogen molecule, followed by the abstraction of a proton from the remaining CHOH 2+ fragment by the roaming H 2 molecule. This reaction has similarities to the H 2+H 2 + mechanism leading to formation of H 3 + in the universe. These exotic chemical reaction mechanisms, involving roaming H 2 molecules, are found to occur in the ~100 fs timescale. Roaming molecule reactions may help to explain unlikely chemical processes, involving dissociation and formation of multiple chemical bonds, occurring under strong laser fields.

Authors:
 [1];  [1];  [2];  [2];  [2];  [2];  [2];  [2];  [2];  [2];  [2];  [2];  [2];  [1];  [1]; ORCiD logo [1]; ORCiD logo [1];  [3]
  1. Michigan State Univ., East Lansing, MI (United States). Dept. of Chemistry
  2. Kansas State Univ., Manhattan, KS (United States). J.R. Macdonald Lab. and Dept. of Physics
  3. Michigan State Univ., East Lansing, MI (United States). Dept. of Chemistry and Dept. of Physics and Astronomy
Publication Date:
Research Org.:
Michigan State Univ., East Lansing, MI (United States); Kansas State Univ., Manhattan, KS (United States)
Sponsoring Org.:
USDOE; National Science Foundation (NSF)
OSTI Identifier:
1430206
Grant/Contract Number:
SC0002325; FG02-86ER13491; FG02-09ER16115; CHE-1565634
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Scientific Reports
Additional Journal Information:
Journal Volume: 7; Journal Issue: 1; Journal ID: ISSN 2045-2322
Publisher:
Nature Publishing Group
Country of Publication:
United States
Language:
English
Subject:
71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 74 ATOMIC AND MOLECULAR PHYSICS; 38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEAR CHEMISTRY; Atomic and molecular interactions with photons; Chemical physics; Galaxies and clusters; Reaction kinetics and dynamics

Citation Formats

Ekanayake, Nagitha, Nairat, Muath, Kaderiya, Balram, Feizollah, Peyman, Jochim, Bethany, Severt, Travis, Berry, Ben, Pandiri, Kanaka Raju, Carnes, Kevin D., Pathak, Shashank, Rolles, Daniel, Rudenko, Artem, Ben-Itzhak, Itzik, Mancuso, Christopher A., Fales, B. Scott, Jackson, James E., Levine, Benjamin G., and Dantus, Marcos. Mechanisms and time-resolved dynamics for trihydrogen cation (H3 +) formation from organic molecules in strong laser fields. United States: N. p., 2017. Web. doi:10.1038/s41598-017-04666-w.
Ekanayake, Nagitha, Nairat, Muath, Kaderiya, Balram, Feizollah, Peyman, Jochim, Bethany, Severt, Travis, Berry, Ben, Pandiri, Kanaka Raju, Carnes, Kevin D., Pathak, Shashank, Rolles, Daniel, Rudenko, Artem, Ben-Itzhak, Itzik, Mancuso, Christopher A., Fales, B. Scott, Jackson, James E., Levine, Benjamin G., & Dantus, Marcos. Mechanisms and time-resolved dynamics for trihydrogen cation (H3 +) formation from organic molecules in strong laser fields. United States. doi:10.1038/s41598-017-04666-w.
Ekanayake, Nagitha, Nairat, Muath, Kaderiya, Balram, Feizollah, Peyman, Jochim, Bethany, Severt, Travis, Berry, Ben, Pandiri, Kanaka Raju, Carnes, Kevin D., Pathak, Shashank, Rolles, Daniel, Rudenko, Artem, Ben-Itzhak, Itzik, Mancuso, Christopher A., Fales, B. Scott, Jackson, James E., Levine, Benjamin G., and Dantus, Marcos. Wed . "Mechanisms and time-resolved dynamics for trihydrogen cation (H3 +) formation from organic molecules in strong laser fields". United States. doi:10.1038/s41598-017-04666-w. https://www.osti.gov/servlets/purl/1430206.
@article{osti_1430206,
title = {Mechanisms and time-resolved dynamics for trihydrogen cation (H3 +) formation from organic molecules in strong laser fields},
author = {Ekanayake, Nagitha and Nairat, Muath and Kaderiya, Balram and Feizollah, Peyman and Jochim, Bethany and Severt, Travis and Berry, Ben and Pandiri, Kanaka Raju and Carnes, Kevin D. and Pathak, Shashank and Rolles, Daniel and Rudenko, Artem and Ben-Itzhak, Itzik and Mancuso, Christopher A. and Fales, B. Scott and Jackson, James E. and Levine, Benjamin G. and Dantus, Marcos},
abstractNote = {Strong-field laser-matter interactions often lead to exotic chemical reactions. Trihydrogen cation formation from organic molecules is one such case that requires multiple bonds to break and form. Here, we present evidence for the existence of two different reaction pathways for H3+ formation from organic molecules irradiated by a strong-field laser. Assignment of the two pathways was accomplished through analysis of femtosecond time-resolved strong-field ionization and photoion-photoion coincidence measurements carried out on methanol isotopomers, ethylene glycol, and acetone. Ab initio molecular dynamics simulations suggest the formation occurs via two steps: the initial formation of a neutral hydrogen molecule, followed by the abstraction of a proton from the remaining CHOH2+ fragment by the roaming H2 molecule. This reaction has similarities to the H2+H2+ mechanism leading to formation of H3+ in the universe. These exotic chemical reaction mechanisms, involving roaming H2 molecules, are found to occur in the ~100 fs timescale. Roaming molecule reactions may help to explain unlikely chemical processes, involving dissociation and formation of multiple chemical bonds, occurring under strong laser fields.},
doi = {10.1038/s41598-017-04666-w},
journal = {Scientific Reports},
number = 1,
volume = 7,
place = {United States},
year = {Wed Jul 05 00:00:00 EDT 2017},
month = {Wed Jul 05 00:00:00 EDT 2017}
}

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  • The reaction between ground state carbon atoms, C({sup 3}P{sub j}), and acetylene, C{sub 2}H{sub 2}(X{sup 1}{Sigma}{sub g}{sup +}), is studied at three collision energies between 8.8 and 45.0 kJmol{sup {minus}1} using the crossed molecular beams technique. Product angular distributions and time-of-flight spectra of C{sub 3}H at m/e=37 are recorded. Forward-convolution fitting of the data yields weakly polarized center-of-mass angular flux distributions decreasingly forward scattered with respect to the carbon beam as the collision energy rises from 8.8 to 28.0 kJmol{sup {minus}1}, and isotropic at 45.0 kJmol{sup {minus}1}. Reaction dynamics inferred from the experimental data and {ital ab initio} calculations onmore » the triplet C{sub 3}H{sub 2} and doublet C{sub 3}H potential energy surface suggest two microchannels initiated by addition of C({sup 3}P{sub j}) either to one acetylenic carbon to form s-{ital trans} propenediylidene or to two carbon atoms to yield triplet cyclopropenylidene via loose transition states located at their centrifugal barriers. Propenediylidene rotates around its B/C axis and undergoes [2,3]-H-migration to propargylene, followed by C{endash}H bond cleavage via a symmetric exit transition state to l-C{sub 3}H(X{sup 2}{Pi}{sub j}) and H. Direct stripping dynamics contribute to the forward-scattered second microchannel to form c-C{sub 3}H(X{sup 2}B{sub 2}) and H. This contribution is quenched with rising collision energy. The explicit identification of l-C{sub 3}H(X{sup 2}{Pi}{sub j}) and c-C{sub 3}H(X{sup 2}B{sub 2}) under single collision conditions represents a one-encounter mechanism to build up hydrocarbon radicals in the interstellar medium and resembles a more realistic synthetic route to interstellar C{sub 3}H isomers than hitherto postulated ion{endash}molecule reactions. (Abstract Truncated)« less
  • The reaction between ground-state carbon atoms, C({sup 3}{ital P}{sub {ital j}}), and ethylene, C{sub 2}H{sub 4}({ital X}{sup 1}{ital A}{sub {ital g}}), was studied at average collision energies of 17.1 and 38.3 kJmol{sup {minus}1} using the crossed molecular beams technique. Product angular distributions and time-of-flight spectra of {ital m}/{ital e}=39 were recorded. Forward-convolution fitting of the results yields a maximum energy release as well as angular distributions consistent with the formation of the propargyl radical in its {ital X}{sup 2}{ital B}{sub 2} state. Reaction dynamics inferred from the experimental data indicate two microchannels, both initiated by attack of the carbon atommore » to the {pi}-orbital of the ethylene molecule via a loose, reactant like transition state located at the centrifugal barrier. Following {ital C}{sub {ital s}} symmetry on the ground state {sup 3}{ital A}{double_prime} surface, the initially formed triplet cyclopropylidene complex rotates in a plane roughly perpendicular to the total angular momentum vector around its {ital C}-axis, undergoes ring opening to triplet allene, and decomposes via hydrogen emission through a tight transition state to the propargyl radical. The initial and final orbital angular momenta {bold L} and {bold L}{prime} are weakly coupled and result in an isotropic center-of-mass angular distribution. A second microchannel arises from A-like rotations of the cyclopropylidene complex, followed by ring opening and H-atom elimination. In this case, a strong {bold L}-{bold L}{prime} correlation leads to a forward-scattered center-of-mass angular distribution. The explicit identification of C{sub 3}H{sub 3} under single collision conditions represents a single, one-step mechanism to build up hydrocarbon radicals. (Abstract Truncated)« less
  • The reaction between ground state carbon atoms and propylene, C{sub 3}H{sub 6}, was studied at average collision energies of 23.3 and 45.0 kJmol{sup {minus}1} using the crossed molecular beam technique. Product angular distributions and time-of-flight spectra of C{sub 4}H{sub 5} at m/e=53 were recorded. Forward-convolution fitting of the data yields a maximum energy release as well as angular distributions consistent with the formation of methylpropargyl radicals. Reaction dynamics inferred from the experimental results suggest that the reaction proceeds on the lowest {sup 3}A surface via an initial addition of the carbon atom to the {pi}-orbital to form a triplet methylcyclopropylidenemore » collision complex followed by ring opening to triplet 1,2-butadiene. Within 0.3{endash}0.6 ps, 1,2-butadiene decomposes through carbon{endash}hydrogen bond rupture to atomic hydrogen and methylpropargyl radicals. The explicit identification of C{sub 4}H{sub 5} under single collision conditions represents a further example of a carbon{endash}hydrogen exchange in reactions of ground state carbon with unsaturated hydrocarbons. This versatile machine represents an alternative pathway to build up unsaturated hydrocarbon chains in combustion processes, chemical vapor deposition, and in the interstellar medium. {copyright} {ital 1997 American Institute of Physics.}« less
  • The reaction between ground-state carbon atoms, C({sup 3}{ital P}{sub {ital j}}), and methylacetylene, CH{sub 3}CCH ({ital X}{sup 1}{ital A}{sub 1}), was studied at average collision energies of 20.4 and 33.2 kJmol{sup -1} using the crossed molecular beams technique. Product angular distributions and time-of-flight spectra of C{sub 4}H{sub 3} at {ital m/e}=51 were recorded. Forward-convolution fitting of the data yields weakly polarized center-of-mass angular flux distributions isotropic at lower, but forward scattered with respect to the carbon beam at a higher collision energy. The translational energy flux distributions peak at 30{endash}60 kJmol{sup {minus}1} and show an average fractional translational energy releasemore » of 22-30%. The maximum energy release as well as the angular distributions are consistent with the formation of the {ital n}-C{sub 4}H{sub 3} radical in its electronic ground state. Reaction dynamics inferred from these distributions indicate that the carbon atom attacks the {pi}-orbitals of the methylacetylene molecule via a loose, reactant like transition state located at the centrifugal barrier. The initially formed triplet 1-methylpropendiylidene complex rotates in a plane almost perpendicular to the total angular momentum vector around the {ital B}/{ital C}-axes and undergoes [2,3]-hydrogen migration to triplet 1-methylpropargylene. Within 1-2 ps, the complex decomposes via C-H bond cleavage to {ital n}-C{sub 4}H{sub 3} and atomic hydrogen. The exit transition state is found to be tight and located at least 30-60 kJmol{sup -1} above the products. The explicit identification of the {ital n}-C{sub 4}H{sub 3} radical under single collision conditions represents a further example of a carbon{endash}hydrogen exchange in reactions of ground state carbon atoms with unsaturated hydrocarbons. This channel opens a versatile pathway to synthesize extremely reactive hydrocarbon radicals relevant to combustion processes as well as interstellar chemistry.« less