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  • Thermal decomposition and isomerization of 1-Butyl and 1-Pentyl radical by flash pyrolysis vacuum ultraviolet photoionization time-of-flight mass spectrometry
Title: Thermal decomposition and isomerization of 1-Butyl and 1-Pentyl radical by flash pyrolysis vacuum ultraviolet photoionization time-of-flight mass spectrometry
Thermal decomposition and isomerization of 1-butyl and 1-pentyl radical were studied in the temperature range of 500–1480 K on a short time scale of 20–100 µs using flash pyrolysis vacuum ultraviolet single-photon ionization time-of-flight mass spectrometry. 1-Bromobutane and 1-bromopentane were used as precursors for the 1-butyl and 1-pentyl radical, respectively. The reactive intermediates in the thermal dissociation reactions were directly observed. The 1-butyl radical decomposed to ethene and ethyl radical with ethyl radical rapidly losing an H atom to form a second ethene molecule. Loss of H atom from butyl radical was also a significant decomposition channel. Isomerization of 1-butyl via 1,3-H migration was observed as a minor channel at 1380 K and above with a branching ratio of less than 3% at 1430 K. The 1-pentyl radical was observed to decompose mainly by isomerization to 2-pentyl radical followed by β-scission to produce propene and ethyl radicals at temperatures approximately 900 K and below. Above 900 K, β-scission of 1-pentyl to produce ethene and 1-propyl radical became increasingly important. Isomerization to 3-pentyl was verified to be a minor channel.  more » « less
Award ID(s):
2155232
PAR ID:
10583663
Author(s) / Creator(s):
;
Publisher / Repository:
SAG
Date Published:
Journal Name:
European Journal of Mass Spectrometry
Volume:
30
Issue:
3-4
ISSN:
1469-0667
Page Range / eLocation ID:
161 to 170
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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