Time-dependent Density Functional Theory Study on the Electronically Excited States of N-Methylformamide in Aqueous Solution  

作　　者：尹淑慧 马超 何香怡 郭明星 许雪松 宋哲 韩易轩 

机构地区：[1]Department of Physics,Dalian Maritime University [2]School of Physics and Electronic Technology,Liaoning Normal University [3]Environmental Science and Engineering College,Dalian Maritime University

出　　处：《Chinese Journal of Structural Chemistry》2012年第7期925-932,共8页结构化学（英文）

基　　金：Supported by the Fundamental Research Funds for the Central Universities (No.2012QN066,2011QN142)

摘　　要：Excited-state hydrogen-bonding dynamics of N-methylformamide （NMF） in water has been investigated by time-dependent density functional theory （TDDFT） method. The ground-state geometry optimizations were calculated by density functional theory （DFT） method, while the electronic transition energies and corresponding oscillation strengths of the low-lying electronically excited states of isolated NMF, water monomers and the hydrogen-bonded NMF-H 2 O were calculated by TDDFT method. According to Zhao＇s rule on the excited-state hydrogen bonding dynamics, our results demonstrate that the intermolecular hydrogen bond C=O···O-H is strengthened and weakened in different electronically excited states. The hydrogen bond strengthening and weakening in the electronically excited state plays an important role in the photophysics of NMF in solutions.Excited-state hydrogen-bonding dynamics of N-methylformamide （NMF） in water has been investigated by time-dependent density functional theory （TDDFT） method. The ground-state geometry optimizations were calculated by density functional theory （DFT） method, while the electronic transition energies and corresponding oscillation strengths of the low-lying electronically excited states of isolated NMF, water monomers and the hydrogen-bonded NMF-H 2 O were calculated by TDDFT method. According to Zhao＇s rule on the excited-state hydrogen bonding dynamics, our results demonstrate that the intermolecular hydrogen bond C=O···O-H is strengthened and weakened in different electronically excited states. The hydrogen bond strengthening and weakening in the electronically excited state plays an important role in the photophysics of NMF in solutions.

关 键 词：hydrogen bond excited state NMF DFT/TDDFT 

分 类 号：O621.2[理学—有机化学]