UV absorption spectrum of the C2 Criegee intermediate CH{sub 3}CHOO

Journal Article · Thu Aug 21 04:00:00 EDT 2014 · Journal of Chemical Physics

DOI:https://doi.org/10.1063/1.4892582· OSTI ID:22420045

Smith, Mica C. ^[1]; Ting, Wei-Lun; Chang, Chun-Hung; Takahashi, Kaito ^[2]; Boering, Kristie A. ^[1]

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1. Department of Chemistry, University of California, Berkeley, Berkeley, California 94720 (United States)
2. Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan (China)

The UV spectrum of CH{sub 3}CHOO was measured by transient absorption in a flow cell at 295 K. The absolute absorption cross sections of CH{sub 3}CHOO were measured by laser depletion in a molecular beam to be (1.06 ± 0.09) × 10{sup −17} cm{sup 2} molecule{sup −1} at 308 nm and (9.7 ± 0.6) × 10{sup −18} cm{sup 2} molecule{sup −1} at 352 nm. After scaling the UV spectrum of CH{sub 3}CHOO to the absolute cross section at 308 nm, the peak UV cross section is (1.27 ± 0.11) × 10{sup −17} cm{sup 2} molecule{sup −1} at 328 nm. Compared to the simplest Criegee intermediate CH{sub 2}OO, the UV absorption band of CH{sub 3}CHOO is similar in intensity but blue shifted by 14 nm, resulting in a 20% slower photolysis rate estimated for CH{sub 3}CHOO in the atmosphere.

• OSTI ID: 22420045
• Journal Information: Journal of Chemical Physics, Journal Name: Journal of Chemical Physics Journal Issue: 7 Vol. 141; ISSN JCPSA6; ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
ABSORPTION
ABSORPTION SPECTRA
COMPARATIVE EVALUATIONS
CROSS SECTIONS
LASERS
MOLECULAR BEAMS
MOLECULES
PEAKS
PHOTOLYSIS
ULTRAVIOLET SPECTRA