Expand this Topic clickable element to expand a topic
Skip to content
Optica Publishing Group
  • Applied Spectroscopy
  • Vol. 61,
  • Issue 2,
  • pp. 230-236
  • (2007)

Absorption Cross-Sections of the C–H Overtone of Volatile Organic Compounds: 2 Methyl-1,3-Butadiene (Isoprene), 1,3-Butadiene, and 2,3-Dimethyl-1,3-Butadiene

Not Accessible

Your library or personal account may give you access

Abstract

Many molecules or transient radicals have well-documented absorption cross-sections in the ultraviolet (UV) region, but their absorption cross-sections in the near-infrared (NIR) region are much less often known and are difficult to measure. We propose a method to determine the unknown NIR absorption cross-sections using the known absorption cross-sections in the UV region, in which single-path UV absorption spectroscopy and NIR continuous wave cavity ringdown spectroscopy (cw-CRDS) are employed in a cross-arm reaction chamber for simultaneous measurements. Without knowing the actual sample partial pressures (or concentrations), the NIR absorption cross-sections can be accurately determined through the two sets of measurements. The method is demonstrated by measuring the NIR absorption cross-section of the first overtone of the asymmetric C–H stretch of 2-methyl-1,3-butadiene (isoprene) (3.24 (±0.16) × 10<sup>−22</sup> cm<sup>2</sup> molecule<sup>−1</sup>) at 1651.52 nm using the known value of the absorption cross-section at 220 nm. The diode laser wavelength was calibrated by atmospheric cavity ringdown spectra of CH<sub>4</sub>, CO<sub>2</sub>, and H<sub>2</sub>O. By comparison with sample pressure measurements, this method can also be used as a pressure calibration means for the reaction chamber, and this has been demonstrated with two additional measurements of the absorption cross-sections of 1,3-butadiene and 2,3-dimethyl-1,3-butadiene (2.50 (± 0.08) × 10<sup>−22</sup> and 2.82 (±0.16) × 10<sup>−22</sup> cm<sup>2</sup> molecule<sup>−1</sup>, respectively) at 1651.52 nm. The applicability of the method to determining absorption cross-sections using the simultaneous measurements of cw-CRDS and single-path absorption spectroscopy is discussed.

PDF Article
More Like This
Temperature and pressure dependence of NH3 and C2H4 absorption cross sections at CO2 laser wavelengths

U. Persson, B. Marthinsson, J. Johansson, and S. T. Eng
Appl. Opt. 19(10) 1711-1715 (1980)

Spectroscopic investigation of methylated amines by a cavity-ringdown-based spectrometer

Dilyan Marinov, Julien M. Rey, Michel G. Müller, and Markus W. Sigrist
Appl. Opt. 46(19) 3981-3986 (2007)

Detection of vapors of explosives and explosive-related compounds by ultraviolet cavity ringdown spectroscopy

Christopher Ramos and Paul J. Dagdigian
Appl. Opt. 46(4) 620-627 (2007)

Cited By

You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an Optica member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access Optica Member Subscription

Select as filters


Select Topics Cancel
© Copyright 2024 | Optica Publishing Group. All Rights Reserved