利用单光子零动能光电子能谱研究氯乙烯阳离子的振动结构。

Vibrational structure of vinyl chloride cation studied by using one-photon zero-kinetic energy photoelectron spectroscopy.

作者信息

Zhang Ping, Li Juan, Mo Yuxiang

机构信息

Department of Physics and Key Laboratory for Atomic and Molecular Nanosciences, Tsinghua University, Beijing 100084, China.

出版信息

J Phys Chem A. 2007 Sep 6;111(35):8531-5. doi: 10.1021/jp073279f. Epub 2007 Aug 15.

DOI:10.1021/jp073279f

PMID:17696413

Abstract

The vibrational structure of vinyl chloride cation, CH(2)CHCl+ (X(2)A' '), has been studied by vacuum ultraviolet (VUV) zero-kinetic energy (ZEKE) photoelectron spectroscopy. Among nine symmetric vibrational modes, the fundamental frequencies of six modes have been determined. The first overtone of the out-of-plane CH(2) twist vibrational mode has been also measured. In addition to these, the combination and overtone bands of the above vibrational modes about 4500 cm(-1) above the ground state have been observed in the ZEKE spectrum. The vibrational band intensities of the ZEKE spectrum can be described approximately by the Franck-Condon factors with harmonic approximation. The ZEKE spectrum has been assigned based on the harmonic frequencies and Franck-Condon factors from theoretical calculations. The ionization energy (IE) of CH(2)CHCl is determined as 80705.5 +/- 2.5 (cm(-1)) or 10.0062 +/- 0.0003 (eV).

摘要

采用真空紫外（VUV）零动能（ZEKE）光电子能谱研究了氯乙烯阳离子CH₂CHCl⁺（X²A''）的振动结构。在九个对称振动模式中，已确定了六个模式的基频。还测量了面外CH₂扭转振动模式的第一泛音。除此之外，在ZEKE光谱中还观察到了上述振动模式在基态以上约4500 cm⁻¹处的组合带和泛音带。ZEKE光谱的振动带强度可用含简谐近似的弗兰克 - 康登因子近似描述。基于理论计算的简谐频率和弗兰克 - 康登因子对ZEKE光谱进行了归属。确定CH₂CHCl的电离能（IE）为80705.5±2.5（cm⁻¹）或10.0062±0.0003（eV）。