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Title: Identification of C5Hx isomers in fuel-rich flames by photoionization mass spectrometry and electronic structure calculations.

Abstract

No abstract prepared.

Authors:
 [1];  [1];  [2];  [3];  [3];  [4];  [5];  [6];  [1]
  1. (Cornell University, Ithaca, NY)
  2. (University Bielefeld, Bielefeld, Germany)
  3. (Sandia National Laboratories, Livermore, CA)
  4. (Argonne National Laboratory, Argonne, IL)
  5. (University of Massachusetts, Amherst, MA)
  6. (University of Massachusetts, Amherst, MA)
Publication Date:
Research Org.:
Sandia National Laboratories
Sponsoring Org.:
USDOE
OSTI Identifier:
877722
Report Number(s):
SAND2005-7611J
TRN: US200608%%561
DOE Contract Number:
AC04-94AL85000
Resource Type:
Journal Article
Resource Relation:
Journal Name: Proposed for publication in the Journal of Physical Chemistry A.
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; HYDROCARBONS; ELECTRONIC STRUCTURE; FLAMES; ISOMERS; MASS SPECTROSCOPY; PHOTOIONIZATION; COMBUSTION KINETICS

Citation Formats

Wang, Juan, Cool, Terrill A., Kohse-Hoinghaus, Katharina, Miller, James A., Hansen, Nils, Klippenstein, Stephen J., Law, Matthew E., Westmoreland, Phillip R., and Kasper, Tina Silvia. Identification of C5Hx isomers in fuel-rich flames by photoionization mass spectrometry and electronic structure calculations.. United States: N. p., 2005. Web.
Wang, Juan, Cool, Terrill A., Kohse-Hoinghaus, Katharina, Miller, James A., Hansen, Nils, Klippenstein, Stephen J., Law, Matthew E., Westmoreland, Phillip R., & Kasper, Tina Silvia. Identification of C5Hx isomers in fuel-rich flames by photoionization mass spectrometry and electronic structure calculations.. United States.
Wang, Juan, Cool, Terrill A., Kohse-Hoinghaus, Katharina, Miller, James A., Hansen, Nils, Klippenstein, Stephen J., Law, Matthew E., Westmoreland, Phillip R., and Kasper, Tina Silvia. Thu . "Identification of C5Hx isomers in fuel-rich flames by photoionization mass spectrometry and electronic structure calculations.". United States. doi:.
@article{osti_877722,
title = {Identification of C5Hx isomers in fuel-rich flames by photoionization mass spectrometry and electronic structure calculations.},
author = {Wang, Juan and Cool, Terrill A. and Kohse-Hoinghaus, Katharina and Miller, James A. and Hansen, Nils and Klippenstein, Stephen J. and Law, Matthew E. and Westmoreland, Phillip R. and Kasper, Tina Silvia},
abstractNote = {No abstract prepared.},
doi = {},
journal = {Proposed for publication in the Journal of Physical Chemistry A.},
number = ,
volume = ,
place = {United States},
year = {Thu Dec 01 00:00:00 EST 2005},
month = {Thu Dec 01 00:00:00 EST 2005}
}
  • No abstract prepared.
  • In present study, photoionization and dissociation of acetic acid dimers have been studied with the synchrotron vacuum ultraviolet photoionization mass spectrometry and theoretical calculations. Besides the intense signal corresponding to protonated cluster ions (CH{sub 3}COOH){sub n}{center_dot}H{sup +}, the feature related to the fragment ions (CH{sub 3}COOH)H{sup +}{center_dot}COO (105 amu) via {beta}-carbon-carbon bond cleavage is observed. By scanning photoionization efficiency spectra, appearance energies of the fragments (CH{sub 3}COOH){center_dot}H{sup +} and (CH{sub 3}COOH)H{sup +}{center_dot}COO are obtained. With the aid of theoretical calculations, seven fragmentation channels of acetic acid dimer cations were discussed, where five cation isomers of acetic acid dimer are involved.more » While four of them are found to generate the protonated species, only one of them can dissociate into a C-C bond cleavage product (CH{sub 3}COOH)H{sup +}{center_dot}COO. After surmounting the methyl hydrogen-transfer barrier 10.84 {+-} 0.05 eV, the opening of dissociative channel to produce ions (CH{sub 3}COOH){sup +} becomes the most competitive path. When photon energy increases to 12.4 eV, we also found dimer cations can be fragmented and generate new cations (CH{sub 3}COOH){center_dot}CH{sub 3}CO{sup +}. Kinetics, thermodynamics, and entropy factors for these competitive dissociation pathways are discussed. The present report provides a clear picture of the photoionization and dissociation processes of the acetic acid dimer in the range of the photon energy 9-15 eV.« less
  • No abstract prepared.
  • We have developed an effusive laser photodissociation radical source, aiming for the production of vibrationally relaxed radicals. Employing this radical source, we have measured the vacuum ultraviolet (VUV) photoionization efficiency (PIE) spectrum of the propargyl radical (C{sub 3}H{sub 3}) formed by the 193 nm excimer laser photodissociation of propargyl chloride in the energy range of 8.5-9.9 eV using high-resolution (energy bandwidth=1 meV) multibunch synchrotron radiation. The VUV-PIE spectrum of C{sub 3}H{sub 3} thus obtained is found to exhibit pronounced autoionization features, which are tentatively assigned as members of two vibrational progressions of C{sub 3}H{sub 3} in excited autoionizing Rydberg states.more » The ionization energy (IE=8.674{+-}0.001 eV) of C{sub 3}H{sub 3} determined by a small steplike feature resolved at the photoionization onset of the VUV-PIE spectrum is in excellent agreement with the IE value reported in a previous pulsed field ionization-photoelectron study. We have also calculated the Franck-Condon factors (FCFs) for the photoionization transitions C{sub 3}H{sub 3}{sup +}(X-tilde;{nu}{sub i},i=1-12)<-C{sub 3}H{sub 3}(X-tilde). The comparison between the pattern of FCFs and the autoionization peaks resolved in the VUV-PIE spectrum of C{sub 3}H{sub 3} points to the conclusion that the resonance-enhanced autoionization mechanism is most likely responsible for the observation of pronounced autoionization features. We also present here the VUV-PIE spectra for the mass 39 ions observed in the VUV synchrotron-based photoionization mass spectrometric sampling of several premixed flames. The excellent agreement of the IE value and the pattern of autoionizing features of the VUV-PIE spectra observed in the photodissociation and flames studies has provided an unambiguous identification of the propargyl radical as an important intermediate in the premixed combustion flames. The discrepancy found between the PIE spectra obtained in flames and photodissociation at energies above the IE(C{sub 3}H{sub 3}) suggests that the PIE spectra obtained in flames might have contributions from the photoionization of vibrationally excited C{sub 3}H{sub 3} and/or the dissociative photoionization processes involving larger hydrocarbon species formed in flames.« less