標題: | Infrared Spectroscopic Investigation of the Acidic CH Bonds in Cationic n-Alkanes: Pentane, Hexane, and Heptane |
作者: | Xie, Min Matsuda, Yoshiyuki Fujii, Asuka 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: | 18-Aug-2016 |
摘要: | Radical cations of n-alkanes (pentane, hexane, and heptane) in the gas phase are investigated by infrared predissociation spectroscopy with the argon Or nitrogen tagging. All-trans and gauche-involving conformers are identified for these cations by comparisons of observed infrared spectra and vibrational simulations. Intense CH stretch bands are observed in the frequency region lower than the normal alkyl CH stretch frequency. These low frequencies and high intensities of the CH stretch bands are caused by the CH bond weakening and the enhanced positive charge of the hydrogen atoms through the delocalization of the sigma electron in the CH bonds. These effects of the delocalization of the a electron result in the enhanced acidity of the CH bonds. The conformation as well as alkyl chain length dependence of the acidity of the CH bonds is demonstrated by the CH stretch frequency shift trend. |
URI: | http://dx.doi.org/10.1021/acs.jpca.6b05567 http://hdl.handle.net/11536/134083 |
ISSN: | 1089-5639 |
DOI: | 10.1021/acs.jpca.6b05567 |
期刊: | JOURNAL OF PHYSICAL CHEMISTRY A |
Volume: | 120 |
Issue: | 32 |
起始頁: | 6351 |
結束頁: | 6356 |
Appears in Collections: | Articles |