MCl2（M = C、Si、Ge、Sn、Pb）的振动高分辨电子光谱以及MCl2(.)的光电子能谱

Vibrationally high-resolved electronic spectra of MCl2 (M=C, Si, Ge, Sn, Pb) and photoelectron spectra of MCl2(.).

作者信息

Ran Yibin, Pang Min, Shen Wei, Li Ming, He Rongxing

机构信息

Key Laboratory of Luminescence and Real-Time Analytical chemistry (Southwest University), Ministry of Education, College of Chemistry and Chemical Engineering, Southwest University, Chongqing 400715, China.

出版信息

Spectrochim Acta A Mol Biomol Spectrosc. 2016 Oct 5;167:1-11. doi: 10.1016/j.saa.2016.05.020. Epub 2016 May 18.

DOI:10.1016/j.saa.2016.05.020

PMID:27280730

Abstract

We systematically studied the vibrational-resolved electronic spectra of group IV dichlorides using the Franck-Condon approximation combined with the Duschinsky and Herzberg-Teller effects in harmonic and anharmonic frameworks (only the simulation of absorption spectra includes the anharmonicity). Calculated results showed that the band shapes of simulated spectra are in accordance with those of the corresponding experimental or theoretical ones. We found that the symmetric bend mode in progression of absorption is the most active one, whereas the main contributor in photoelectron spectra is the symmetric stretching mode. Moreover, the Duschinsky and anharmonic effects exert weak influence on the absorption spectra, except for PbCl2 molecule. The theoretical insights presented in this work are significant in understanding the photophysical properties of MCl2 (M=C, Si, Ge, Sn, Pb) and studying the Herzberg-Teller and the anharmonic effects on the absorption spectra of new dichlorides of this main group.

摘要

我们采用弗兰克 - 康登近似，结合杜申斯基效应和赫兹伯格 - 泰勒效应，在谐波和非谐波框架下（仅吸收光谱模拟包含非谐性），系统地研究了 IV 族二氯化物的振动分辨电子光谱。计算结果表明，模拟光谱的能带形状与相应的实验或理论光谱一致。我们发现，吸收跃迁中的对称弯曲模式是最活跃的模式，而光电子能谱中的主要贡献模式是对称拉伸模式。此外，除了 PbCl₂ 分子外，杜申斯基效应和非谐效应对吸收光谱的影响较弱。这项工作中提出的理论见解对于理解 MCl₂（M = C、Si、Ge、Sn、Pb）的光物理性质以及研究赫兹伯格 - 泰勒效应和非谐效应在该主族新二氯化物吸收光谱中的作用具有重要意义。