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Title: Infrared absorption of gaseous CH{sub 2}BrOO detected with a step-scan Fourier-transform absorption spectrometer

Abstract

CH{sub 2}BrOO radicals were produced upon irradiation, with an excimer laser at 248 nm, of a flowing mixture of CH{sub 2}Br{sub 2} and O{sub 2}. A step-scan Fourier-transform spectrometer coupled with a multipass absorption cell was employed to record temporally resolved infrared (IR) absorption spectra of reaction intermediates. Transient absorption with origins at 1276.1, 1088.3, 961.0, and 884.9 cm{sup −1} are assigned to ν{sub 4} (CH{sub 2}-wagging), ν{sub 6} (O–O stretching), ν{sub 7} (CH{sub 2}-rocking mixed with C–O stretching), and ν{sub 8} (C–O stretching mixed with CH{sub 2}-rocking) modes of syn-CH{sub 2}BrOO, respectively. The assignments were made according to the expected photochemistry and a comparison of observed vibrational wavenumbers, relative IR intensities, and rotational contours with those predicted with the B3LYP/aug-cc-pVTZ method. The rotational contours of ν{sub 7} and ν{sub 8} indicate that hot bands involving the torsional (ν{sub 12}) mode are also present, with transitions 7{sub 0}{sup 1}12{sub v}{sup v} and 8{sub 0}{sup 1}12{sub v}{sup v}, v = 1–10. The most intense band (ν{sub 4}) of anti-CH{sub 2}BrOO near 1277 cm{sup −1} might have a small contribution to the observed spectra. Our work provides information for directly probing gaseous CH{sub 2}BrOO with IR spectroscopy, in either the atmosphere ormore » laboratory experiments.« less

Authors:
 [1];  [1]
  1. Department of Applied Chemistry and Institute of Molecular Science, National Chiao Tung University, Hsinchu 30010, Taiwan (China)
Publication Date:
OSTI Identifier:
22310744
Resource Type:
Journal Article
Journal Name:
Journal of Chemical Physics
Additional Journal Information:
Journal Volume: 141; Journal Issue: 16; Other Information: (c) 2014 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; ABSORPTION; ABSORPTION SPECTRA; ALLOCATIONS; EXCIMER LASERS; FOURIER TRANSFORM SPECTROMETERS; FOURIER TRANSFORMATION; INFRARED SPECTRA; IRRADIATION; MIXTURES; PROBES; RADICALS; REACTION INTERMEDIATES

Citation Formats

Huang, Yu-Hsuan, Lee, Yuan-Pern, and Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan. Infrared absorption of gaseous CH{sub 2}BrOO detected with a step-scan Fourier-transform absorption spectrometer. United States: N. p., 2014. Web. doi:10.1063/1.4897982.
Huang, Yu-Hsuan, Lee, Yuan-Pern, & Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan. Infrared absorption of gaseous CH{sub 2}BrOO detected with a step-scan Fourier-transform absorption spectrometer. United States. https://doi.org/10.1063/1.4897982
Huang, Yu-Hsuan, Lee, Yuan-Pern, and Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan. 2014. "Infrared absorption of gaseous CH{sub 2}BrOO detected with a step-scan Fourier-transform absorption spectrometer". United States. https://doi.org/10.1063/1.4897982.
@article{osti_22310744,
title = {Infrared absorption of gaseous CH{sub 2}BrOO detected with a step-scan Fourier-transform absorption spectrometer},
author = {Huang, Yu-Hsuan and Lee, Yuan-Pern and Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan},
abstractNote = {CH{sub 2}BrOO radicals were produced upon irradiation, with an excimer laser at 248 nm, of a flowing mixture of CH{sub 2}Br{sub 2} and O{sub 2}. A step-scan Fourier-transform spectrometer coupled with a multipass absorption cell was employed to record temporally resolved infrared (IR) absorption spectra of reaction intermediates. Transient absorption with origins at 1276.1, 1088.3, 961.0, and 884.9 cm{sup −1} are assigned to ν{sub 4} (CH{sub 2}-wagging), ν{sub 6} (O–O stretching), ν{sub 7} (CH{sub 2}-rocking mixed with C–O stretching), and ν{sub 8} (C–O stretching mixed with CH{sub 2}-rocking) modes of syn-CH{sub 2}BrOO, respectively. The assignments were made according to the expected photochemistry and a comparison of observed vibrational wavenumbers, relative IR intensities, and rotational contours with those predicted with the B3LYP/aug-cc-pVTZ method. The rotational contours of ν{sub 7} and ν{sub 8} indicate that hot bands involving the torsional (ν{sub 12}) mode are also present, with transitions 7{sub 0}{sup 1}12{sub v}{sup v} and 8{sub 0}{sup 1}12{sub v}{sup v}, v = 1–10. The most intense band (ν{sub 4}) of anti-CH{sub 2}BrOO near 1277 cm{sup −1} might have a small contribution to the observed spectra. Our work provides information for directly probing gaseous CH{sub 2}BrOO with IR spectroscopy, in either the atmosphere or laboratory experiments.},
doi = {10.1063/1.4897982},
url = {https://www.osti.gov/biblio/22310744}, journal = {Journal of Chemical Physics},
issn = {0021-9606},
number = 16,
volume = 141,
place = {United States},
year = {Tue Oct 28 00:00:00 EDT 2014},
month = {Tue Oct 28 00:00:00 EDT 2014}
}