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This content will become publicly available on June 29, 2018

Title: Tabletop Femtosecond VUV Photoionization and PEPICO Detection of Microreactor Pyrolysis Products

Here, we report the combination of tabletop vacuum ultraviolet photoionization with photoion--photoelectron coincidence spectroscopy for sensitive, isomer-specific detection of nascent products from a pyrolysis microreactor. Results on several molecules demonstrate two essential capabilities that are very straightforward to implement: the ability to differentiate isomers, and to distinguish thermal products from dissociative ionization. We derive vacuum ultraviolet light is from a commercial tabletop femtosecond laser system, allowing data to be collected at 10 kHz; this high repetition rate is critical for coincidence techniques. The photoion—photoelectron coincidence spectrometer uses the momentum of the ion to identify dissociative ionization events, and coincidence techniques to provide a photoelectron spectrum specific to each mass, which is used to distinguish different isomers. We also have used this spectrometer to detect the pyrolysis products that result from the thermal cracking of acetaldehyde, cyclohexene, and 2-butanol. The photoion—photoelectron spectrometer can detect and identify organic radicals and reactive intermediates that result from pyrolysis. Direct comparison of laboratory and synchrotron data illustrate the advantages and potential of this approach.
Authors:
ORCiD logo [1] ;  [2] ;  [2] ;  [2] ;  [1] ; ORCiD logo [2] ;  [1] ;  [1] ; ORCiD logo [1]
  1. Univ. of Colorado, Boulder, CO (United States). JILA and Dept. of Physics
  2. Univ. of Colorado, Boulder, CO (United States). Dept. of Chemistry
Publication Date:
Grant/Contract Number:
FG02-99ER14982; AC02-05CH11231; CBET-1403979
Type:
Accepted Manuscript
Journal Name:
Journal of Physical Chemistry. A, Molecules, Spectroscopy, Kinetics, Environment, and General Theory
Additional Journal Information:
Journal Volume: 121; Journal Issue: 28; Journal ID: ISSN 1089-5639
Publisher:
American Chemical Society
Research Org:
Univ. of Colorado, Boulder, CO (United States)
Sponsoring Org:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)
Country of Publication:
United States
Language:
English
Subject:
21 SPECIFIC NUCLEAR REACTORS AND ASSOCIATED PLANTS
OSTI Identifier:
1372114