顺式和反式-1,3-戊二烯的C-H伸缩泛音光谱。

CH-stretching overtone spectra of cis- and trans-1,3-pentadiene.

作者信息

Waldrom Ruth J, Kuschel Matthias, Kjaergaard Henrik G, Henry Bryan R

机构信息

Department of Chemistry, University of Otago, P.O. Box 56, Dunedin, New Zealand.

出版信息

J Phys Chem A. 2006 Jan 26;110(3):913-20. doi: 10.1021/jp0549834.

DOI:10.1021/jp0549834

PMID:16419989

Abstract

The room-temperature vapor-phase overtone spectra of cis- and trans-1,3-pentadiene (piperylene) have been recorded in the 5000-17500 cm(-1) region with the use of conventional and intracavity laser photoacoustic spectroscopy. The presence of five nonequivalent olefinic CH bonds and one methyl group in each molecule complicates assignment of the spectra. We have used a harmonically coupled anharmonic oscillator local mode model with one oscillator for each of the nonequivalent CH bonds to calculate the CH-stretching overtone spectra and thus facilitate assignment of the spectra. Our calculated spectra are in good agreement with the observed spectra. The observed high overtone spectra are distinctively different despite the similarity of the two molecules and the numerous and broad transitions.

摘要

利用传统的和腔内激光光声光谱技术，在5000 - 17500 cm⁻¹区域记录了顺式和反式1,3 - 戊二烯（异戊二烯）的室温气相泛音光谱。每个分子中存在五个不等价的烯属CH键和一个甲基，这使得光谱的归属变得复杂。我们使用了一个谐波耦合非谐振子局域模式模型，为每个不等价的CH键设置一个振子，来计算CH伸缩泛音光谱，从而便于光谱的归属。我们计算得到的光谱与观测光谱吻合良好。尽管这两个分子相似且有众多宽泛的跃迁，但观测到的高泛音光谱却明显不同。