Electron attachment to C{sub 2} fluorocarbon radicals at high temperature

Shuman, Nicholas S.; Miller, Thomas M.

doi:10.1063/1.4829447

Title: Electron attachment to C{sub 2} fluorocarbon radicals at high temperature

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Abstract

Thermal electron attachment to the radical species C{sub 2}F{sub 3} and C{sub 2}F{sub 5} has been studied over the temperature range 300–890 K using the Variable Electron and Neutral Density Attachment Mass Spectrometry technique. Both radicals exclusively undergo dissociative attachment to yield F{sup −}. The rate constant for C{sub 2}F{sub 5} shows little dependence over the temperature range, remaining ∼4 × 10{sup −9} cm{sup 3} s{sup −1}. The rate constant for C{sub 2}F{sub 3} attachment rises steeply with temperature from 3 × 10{sup −11} cm{sup 3} s{sup −1} at 300 K to 1 × 10{sup −9} cm{sup 3} s{sup −1} at 890 K. The behaviors of both species at high temperature are in agreement with extrapolations previously made from data below 600 K using a recently developed kinetic modeling approach. Measurements were also made on C{sub 2}F{sub 3}Br and C{sub 2}F{sub 5}Br (used in this work as precursors to the radicals) over the same temperature range, and, for C{sub 2}F{sub 5}Br as a function of electron temperature. The attachment rate constants to both species rise with temperature following Arrhenius behavior. The attachment rate constant to C{sub 2}F{sub 5}Br falls with increasing electron temperature, in agreement with the kinetic modeling. The current data fall inmore »« less

Authors:: Shuman, Nicholas S.; Miller, Thomas M.

Publication Date:: Thu Nov 14 00:00:00 EST 2013

OSTI Identifier:: 22251484

Resource Type:: Journal Article

Journal Name:: Journal of Chemical Physics

Additional Journal Information:: Journal Volume: 139; Journal Issue: 18; Other Information: (c) 2013 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA); Journal ID: ISSN 0021-9606

Country of Publication:: United States

Language:: English

Subject:: 37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; DENSITY; ELECTRON TEMPERATURE; ELECTRONS; EXTRAPOLATION; FORECASTING; MASS SPECTROSCOPY; RADICALS; REACTION KINETICS; SIMULATION

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                    Shuman, Nicholas S., Miller, Thomas M., and Viggiano, Albert A., E-mail: afrl.rvborgmailbox@kirtland.af.mil. Electron attachment to C{sub 2} fluorocarbon radicals at high temperature.  United States: N. p., 2013. 
        Web.  doi:10.1063/1.4829447.

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                    Shuman, Nicholas S., Miller, Thomas M., & Viggiano, Albert A., E-mail: afrl.rvborgmailbox@kirtland.af.mil. Electron attachment to C{sub 2} fluorocarbon radicals at high temperature.  United States.  https://doi.org/10.1063/1.4829447

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                    Shuman, Nicholas S., Miller, Thomas M., and Viggiano, Albert A., E-mail: afrl.rvborgmailbox@kirtland.af.mil. 2013.  
        "Electron attachment to C{sub 2} fluorocarbon radicals at high temperature".  United States.  https://doi.org/10.1063/1.4829447.

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@article{osti_22251484,

  title        = {Electron attachment to C{sub 2} fluorocarbon radicals at high temperature},

  author       = {Shuman, Nicholas S. and Miller, Thomas M. and Viggiano, Albert A., E-mail: afrl.rvborgmailbox@kirtland.af.mil},

  abstractNote = {Thermal electron attachment to the radical species C{sub 2}F{sub 3} and C{sub 2}F{sub 5} has been studied over the temperature range 300–890 K using the Variable Electron and Neutral Density Attachment Mass Spectrometry technique. Both radicals exclusively undergo dissociative attachment to yield F{sup −}. The rate constant for C{sub 2}F{sub 5} shows little dependence over the temperature range, remaining ∼4 × 10{sup −9} cm{sup 3} s{sup −1}. The rate constant for C{sub 2}F{sub 3} attachment rises steeply with temperature from 3 × 10{sup −11} cm{sup 3} s{sup −1} at 300 K to 1 × 10{sup −9} cm{sup 3} s{sup −1} at 890 K. The behaviors of both species at high temperature are in agreement with extrapolations previously made from data below 600 K using a recently developed kinetic modeling approach. Measurements were also made on C{sub 2}F{sub 3}Br and C{sub 2}F{sub 5}Br (used in this work as precursors to the radicals) over the same temperature range, and, for C{sub 2}F{sub 5}Br as a function of electron temperature. The attachment rate constants to both species rise with temperature following Arrhenius behavior. The attachment rate constant to C{sub 2}F{sub 5}Br falls with increasing electron temperature, in agreement with the kinetic modeling. The current data fall in line with past predictions of the kinetic modeling approach, again showing the utility of this simplified approach.},

  doi          = {10.1063/1.4829447},

  url          = {https://www.osti.gov/biblio/22251484},
  journal      = {Journal of Chemical Physics},

  issn         = {0021-9606},

  number       = 18,

  volume       = 139,

  place        = {United States},

  year         = {Thu Nov 14 00:00:00 EST 2013},

  month        = {Thu Nov 14 00:00:00 EST 2013}

}

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