High resolution absolute absorption cross sections of the B ̃(1)A'-X ̃(1)A' transition of the CH2OO biradical
| Autor: | Craig Murray, Kara M. Kapnas, YiTien Jou, Jaroslaw Kalinowski, R. Benny Gerber, Elizabeth S. Foreman, David Feng |
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| Rok vydání: | 2015 |
| Předmět: |
Absorption spectroscopy
Extended X-ray absorption fine structure Chemistry Analytical chemistry General Physics and Astronomy Nanotechnology 02 engineering and technology 010402 general chemistry 021001 nanoscience & nanotechnology 01 natural sciences Molecular electronic transition Spectral line 0104 chemical sciences Absorption band Criegee intermediate Physical and Theoretical Chemistry 0210 nano-technology Spectroscopy Absorption (electromagnetic radiation) |
| Zdroj: | Physical chemistry chemical physics : PCCP. 17(48) |
| ISSN: | 1463-9084 |
| Popis: | Carbonyl oxides, or Criegee intermediates, are formed from the gas phase ozonolysis of alkenes and play a pivotal role in night-time and urban area atmospheric chemistry. Significant discrepancies exist among measurements of the strong B ̃(1)A'-X ̃(1)A' electronic transition of the simplest Criegee intermediate, CH2OO in the visible/near-UV. We report room temperature spectra of the B ̃(1)A'-X ̃(1)A' electronic absorption band of CH2OO acquired at higher resolution using both single-pass broadband absorption and cavity ring-down spectroscopy. The new absorption spectra confirm the vibrational structure on the red edge of the band that is absent from ionization depletion measurements. The absolute absorption cross sections over the 362-470 nm range are in good agreement with those reported by Ting et al. Broadband absorption spectra recorded over the temperature range of 276-357 K were identical within their mutual uncertainties, confirming that the vibrational structure is not due to hot bands. |
| Databáze: | OpenAIRE |
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