通过零动能光电子能谱研究CH(3)CN(+)（X(2)E）和CD(3)CN(+)（X(2)E）中的 Jahn-Teller 效应。

The Jahn-Teller effect in CH(3)CN(+) (X(2)E) and CD(3)CN(+) (X(2)E) studied by zero kinetic energy photoelectron spectroscopy.

作者信息

Yang Jie, Zhou Chang, 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. 2005 Nov 10;109(44):9964-8. doi: 10.1021/jp054366f.

DOI:10.1021/jp054366f

PMID:16838913

Abstract

The Jahn-Teller effect in CH(3)CN(+) (X(2)E) and CD(3)CN(+) (X(2)E) has been found experimentally by zero kinetic energy (ZEKE) photoelectron spectroscopy using coherent extreme ultraviolet (XUV) radiation. The vibronic bands of CH(3)CN(+) (X(2)E) and CD(3)CN(+) (X(2)E) at about 4500 cm(-1) above the ground states have been recorded. The spectra consist mainly of the Jahn-Teller active C-C[triple bond]N bending (v(8)), the CN stretching (v(2)), the CH(3) (CD(3)) deforming (v(6)), and the C-C stretching (v(4)) vibronic excitations. The Jahn-Teller active vibronic bands (v(8)) have been assigned with a harmonic model including linear and quadratic Jahn-Teller coupling terms, taking into account only the single mode vibronic excitation. The ionization potentials of CH(3)CN and CD(3)CN have also been determined, and their values are 12.2040(+/-0.001) and 12.2286(+/-0.001) eV, respectively.

摘要

通过使用相干极紫外（XUV）辐射的零动能（ZEKE）光电子能谱实验发现了CH(3)CN(+)（X(2)E）和CD(3)CN(+)（X(2)E）中的 Jahn-Teller 效应。记录了CH(3)CN(+)（X(2)E）和CD(3)CN(+)（X(2)E）在基态以上约4500 cm(-1)处的振转带。光谱主要由 Jahn-Teller 活性的 C-C[三键]N 弯曲（v(8)）、CN 伸缩（v(2)）、CH(3)（CD(3)）变形（v(6)）和 C-C 伸缩（v(4)）振转激发组成。Jahn-Teller 活性振转带（v(8)）已通过包含线性和二次 Jahn-Teller 耦合项的谐波模型进行了归属，仅考虑了单模振转激发。还测定了CH(3)CN和CD(3)CN的电离势，其值分别为12.2040(±0.001)和12.2286(±0.001) eV。