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Title: Quantitative infrared absorption cross sections of isoprene for atmospheric measurements

Abstract

The OH- and O 3- initiated oxidations of isoprene, which is one of the primary volatile organic compounds produced by vegetation, are a major source of atmospheric formaldehyde and other oxygenated organics, yet little quantitative IR data exists for isoprene. We thus report absorption coefficients and integrated band intensities for isoprene in the 600 - 6500 cm -1 region. The pressure-broadened (1 atmosphere N 2) spectra were recorded at 278, 298 and 323 K in a 19.96 cm path length cell at 0.112 cm -1 resolution, using a Bruker 66V FTIR. Composite spectra are derived from a minimum of seven pressures at each temperature.

Authors:
 [1];  [1];  [1];  [1];  [1];  [1]
  1. Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Publication Date:
Research Org.:
Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1166822
Report Number(s):
PNNL-SA-101735
Journal ID: ISSN 1867-1381; 400403209
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Atmospheric Measurement Techniques; Journal Volume: 7; Journal Issue: 11
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES

Citation Formats

Brauer, Carolyn S., Blake, Thomas A., Guenther, Alex B., Sharpe, Steven W., Sams, Robert L., and Johnson, Timothy J.. Quantitative infrared absorption cross sections of isoprene for atmospheric measurements. United States: N. p., 2014. Web. doi:10.5194/amt-7-3839-2014.
Brauer, Carolyn S., Blake, Thomas A., Guenther, Alex B., Sharpe, Steven W., Sams, Robert L., & Johnson, Timothy J.. Quantitative infrared absorption cross sections of isoprene for atmospheric measurements. United States. doi:10.5194/amt-7-3839-2014.
Brauer, Carolyn S., Blake, Thomas A., Guenther, Alex B., Sharpe, Steven W., Sams, Robert L., and Johnson, Timothy J.. 2014. "Quantitative infrared absorption cross sections of isoprene for atmospheric measurements". United States. doi:10.5194/amt-7-3839-2014.
@article{osti_1166822,
title = {Quantitative infrared absorption cross sections of isoprene for atmospheric measurements},
author = {Brauer, Carolyn S. and Blake, Thomas A. and Guenther, Alex B. and Sharpe, Steven W. and Sams, Robert L. and Johnson, Timothy J.},
abstractNote = {The OH- and O3- initiated oxidations of isoprene, which is one of the primary volatile organic compounds produced by vegetation, are a major source of atmospheric formaldehyde and other oxygenated organics, yet little quantitative IR data exists for isoprene. We thus report absorption coefficients and integrated band intensities for isoprene in the 600 - 6500 cm-1 region. The pressure-broadened (1 atmosphere N2) spectra were recorded at 278, 298 and 323 K in a 19.96 cm path length cell at 0.112 cm-1 resolution, using a Bruker 66V FTIR. Composite spectra are derived from a minimum of seven pressures at each temperature.},
doi = {10.5194/amt-7-3839-2014},
journal = {Atmospheric Measurement Techniques},
number = 11,
volume = 7,
place = {United States},
year = 2014,
month =
}
  • Isoprene (C 5H 8, 2-methyl-1,3-butadiene) is a volatile organic compound (VOC) and is one of the primary contributors to annual global VOC emissions. Isoprene is produced primarily by vegetation as well as anthropogenic sources, and its OH- and O 3-initiated oxidations are a major source of atmospheric oxygenated organics. Few quantitative infrared studies have been reported for isoprene, limiting the ability to quantify isoprene emissions via remote or in situ infrared detection. We thus report absorption cross sections and integrated band intensities for isoprene in the 600–6500 cm -1 region. The pressure-broadened (1 atmosphere N 2) spectra were recorded atmore » 278, 298, and 323 K in a 19.94 cm path-length cell at 0.112 cm -1 resolution, using a Bruker IFS 66v/S Fourier transform infrared (FTIR) spectrometer. Composite spectra are derived from a minimum of seven isoprene sample pressures, each at one of three temperatures, and the number densities are normalized to 296 K and 1 atm.« less
    Cited by 5
  • Isoprene (C 5H 8, 2-methyl-1,3-butadiene) is a volatile organic compound (VOC) that is one of the primary contributors to annual global VOC emissions. Produced by vegetation as well as anthropogenic sources, the OH- and O 3-initiated oxidations of isoprene are a major source of atmospheric oxygenated organics. Few quantitative infrared studies have been reported for isoprene, however, limiting the ability to quantify isoprene emissions via stand-off infrared or in situ detection. We thus report absorption coefficients and integrated band intensities for isoprene in the 600–6500 cm −1 region. The pressure-broadened (1 atmosphere N 2) spectra were recorded at 278, 298more » and 323 K in a 19.94 cm path length cell at 0.112 cm −1 resolution, using a Bruker 66v FTIR. Composite spectra are derived from a minimum of seven isoprene sample pressures at each temperature and the number densities are normalized to 296 K and 1 atmosphere.« less
  • Through measurement of the equivalent width (fractional integrated absorption) of collision-broadened lines of the P branch of the HCl fundamental vibration-rotation band at 3.5 ation , the Lorentz half-widths of these lines were determined and optical collision cross sections deduced therefrom. The cross sections obtained were those for collisions between HCI molecules and Ar, CO 2, CO, D 2, H 2, HBr, He, Np, N 2, O 2, as well as other molecules of HCI. One of the more interesting aspects of these cross sections was their dependence on the rotational state of the absorbing molecule and the various formsmore » which this J dependence took for the different foreign gases. The line widths ranged between the extremes of 0.233 and 0.0111 cm -1 atmos -1 while the collision cross sections ranged between 3.04 x 10 -14 and 0.091 x 10 -14 cm. Also reported were recently measured values of the strengths for the first eight lines of the P branch of the HCI fundamental. The strength of this band based on these measurements, was found to be 143 combination rat 5 cm -2 atmos -1 at 300 tained K.« less
  • The temperature dependent UV absorption cross-sections of the hydrochlorofluoroethanes CF{sub 3}CHFCl, CH{sub 3}CF{sub 2}Cl, and CF{sub 3}CHCl{sub 2} are reported. The UV absorption cross-sections were measured over the temperature range 203 to 295 K and the wavelength range 190 to 230 nm. The hydrofluorocarbons CH{sub 3}CF{sub 2}H and CF{sub 3}CH{sub 2}F were also studied at 295 K and upper limits for their UV absorption cross-sections over the wavelength range 190 to 230 nm were obtained. The atmospheric lifetimes of these species were calculated using a one-dimensional atmospheric model, using the kinetic data obtained in the previous paper (Gierczak et al.more » 1991) and the absorption cross-section data obtained in the present study.« less
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