標題: | Infrared identification of the Criegee intermediates syn- and anti-CH3CHOO, and their distinct conformation-dependent reactivity |
作者: | Lin, Hui-Yu Huang, Yu-Hsuan Wang, Xiaohong Bowman, Joel M. Nishimura, Yoshifumi Witek, Henryk A. Lee, Yuan-Pern 應用化學系 應用化學系分子科學碩博班 Department of Applied Chemistry Institute of Molecular science |
公開日期: | 1-五月-2015 |
摘要: | The Criegee intermediates are carbonyl oxides that play critical roles in ozonolysis of alkenes in the atmosphere. So far, the mid-infrared spectrum of only the simplest Criegee intermediate CH2OO has been reported. Methyl substitution of CH2OO produces two conformers of CH3CHOO and consequently complicates the infrared spectrum. Here we report the transient infrared spectrum of syn- and anti-CH3CHOO, produced from CH3CHI + O-2 in a flow reactor, using a step-scan Fourier-transform spectrometer. Guided and supported by high-level full-dimensional quantum calculations, rotational contours of the four observed bands are simulated successfully and provide definitive identification of both conformers. Furthermore, anti-CH3CHOO shows a reactivity greater than syn-CH3CHOO towards NO/NO2; at the later period of reaction, the spectrum can be simulated with only syn-CH3CHOO. Without NO/NO2, anti-CH3CHOO also decays much faster than syn-CH3CHOO. The direct infrared detection of syn-and anti-CH3CHOO should prove useful for field measurements and laboratory investigations of the Criegee mechanism. |
URI: | http://dx.doi.org/10.1038/ncomms8012 http://hdl.handle.net/11536/124828 |
ISSN: | 2041-1723 |
DOI: | 10.1038/ncomms8012 |
期刊: | NATURE COMMUNICATIONS |
Volume: | 6 |
起始頁: | 0 |
結束頁: | 0 |
顯示於類別: | 期刊論文 |