Measurements of the Absorption Line Strength of Hydroperoxyl Radical in the ν(3) Band using a Continuous Wave Quantum Cascade Laser.
Summary of "Measurements of the Absorption Line Strength of Hydroperoxyl Radical in the ν(3) Band using a Continuous Wave Quantum Cascade Laser."
Mid-infrared absorption spectroscopy has been applied to the detection of the hydroperoxyl (HO(2)) radical in pulsed laser photolysis combined with a laser absorption kinetics reactor. Transitions of the ν(3) vibrational band assigned to the O-O stretch mode were probed with a thermoelectrically cooled, continuous wave mid-infrared distributed feedback quantum cascade laser (QCL). The HO(2) radicals were generated with the photolysis of Cl(2)/CH(3)OH/O(2) mixtures at 355 nm. The absorption cross section at each pressure was determined by three methods at 1065.203 cm(-1) for the F(1), 13(1,13) ← 14(1,14) transition in the ν(3) band. From these values, the absolute absorption cross section at zero pressure was estimated. The relative line strengths of other absorptions in the feasible emitting frequency range of the QCL from 1061.17 to 1065.28 cm(-1) were also measured, and agreed with values reproduced from the HITRAN database. The ν(3) band absorption strength was estimated from the analytically obtained absolute absorption cross section and the calculated relative intensity by spectrum simulation, to be 21.4 ± 4.2 km mol(-1), which shows an agreement with results of quantum chemical calculations.
Affiliation
Department of Chemical System Engineering, Graduate School of Engineering, The University of Tokyo , Hongo 7-3-1, Bunkyo-ku, Tokyo 113-8656, Japan.
Journal Details
This article was published in the following journal.
Name: The journal of physical chemistry. A
ISSN: 1520-5215
Pages: 215-22
Links
- PubMed Source: http://www.ncbi.nlm.nih.gov/pubmed/22148191
- DOI: http://dx.doi.org/10.1021/jp207477n
Medical and Biotech [MESH] Definitions
Cytochromes A1
A subclass of heme a containing cytochromes have a reduced alpha-band absorption of 587-592 nm. They are primarily found in microorganisms.
Cytochromes B
Cytochromes of the b group that have alpha-band absorption of 563-564 nm. They occur as subunits in MITOCHONDRIAL ELECTRON TRANSPORT COMPLEX III.
Cytochromes A3
A subclass of heme a containing cytochromes with an alpha-band absorption of 605 nm. They are found in a variety of microorganisms and in eukaryotes as a high-spin cytochrome component of MITOCHONDRIAL ELECTRON TRANSPORT COMPLEX IV.
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Hydroxyl Radical
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