Theoretical investigation on the excited state intramolecular proton transfer in Me_(2)N substituted flavonoid by the time-dependent density functional theory method

作     者：Hang Yin Ying Shi 尹航;石英

作者机构：Institute of Atomic and Molecular PhysicsJilin UniversityChangchun 130012China State Key Laboratory of Supramolecular Structure and MaterialsCollege of ChemistryJilin UniversityChangchun 130012China 

出 版 物：《Chinese Physics B》 (中国物理B(英文版))

年 卷 期：2018年第27卷第5期

页      面：534-538页

核心收录：

学科分类：07[理学] 070203[理学-原子与分子物理] 0702[理学-物理学] 

基　　金：Project supported by the National Basic Research Program of China(Grant No.2013CB922204) the National Natural Science Foundation of China(Grant Nos.11574115 and 11704146) the Natural Science Foundation of Jilin Province,China(Grant No.20150101063JC) 

主　　题：time-dependent density functional theory excited state intramolecular proton transfer intramolecular charge transfer transition state 

摘      要：Time-dependent density functional theory(TDDFT)method is used to investigate the details of the excited state intramolecular proton transfer(ESIPT)process and the mechanism for temperature effect on the Enol^(*)/Keto^(*)emission ratio for the Me_(2)N-substited flavonoid(MNF)*** geometric structures of the S_(0) and S_(1) states are denoted as the Enol,Enol^(*),and Keto*.In addition,the absorption and fluorescence peaks are also *** is noted that the calculated large Stokes shift is in good agreement with the experimental ***,our results confirm that the ESIPT process happens upon photoexcitation,which is distinctly monitored by the formation and disappearance of the characteristic peaks of infrared(IR)spectra involved in the proton transfer and in the potential energy ***,the calculations of highest occupied molecular orbital(HOMO)and lowest unoccupied molecular orbital(LUMO)reveal that the electronegativity change of proton acceptor due to the intramolecular charge redistribution in the S_(1) state induces the ***,the thermodynamic calculation for the MNF shows that the Enol^(*)/Keto^(*)emission ratio decreasing with temperature increasing arises from the barrier lowering of ESIPT.