Quantum chemical study on excited states and charge transfer of oxazolo[4,5-b]-pyridine derivatives  

作　　者：HE RongXing YUAN YanJie SHEN Wei LI Ming YAO Li 

机构地区：[1]College of Chemistry and Chemical Engineering,Southwest University,Chongqing 400715,China [2]Department of Physics,Dalian Maritime University,Dalian 116023,China

出　　处：《Science China Chemistry》2012年第10期2186-2196,共11页中国科学（化学英文版）

基　　金：supported by the National Natural Science Foundation of China (20803059);Chongqing Municipal Natural Science Foundation(2009BB6002)

摘　　要：The excitedstate intramolecular charge transfer of four oxazolo[4,5-b]pyridine derivatives with different electron donating and electron withdrawing groups was investigated using the time-dependent density functional theory. The vertical excitation energies and the electronic structures were explored. Their distinct properties of absorption and fluorescence spectra in solvent phase were explained according to the electronic coupling matrix elements calculated by the Mulliken-Hush theory. The sub-stituent on the oxazolo[4,5-b]pyridines will remarkably change their spectra properties and increase the first excited-state dipole moments. The effect of protonation on the absorption and fluorescence spectra was also investigated systematically. Our study suggests that the present method is feasible to explain charge transfer excitation and predict the properties of absorption and emission spectra in the studied systems.The excitedstate intramolecular charge transfer of four oxazolo[4,5-b]pyridine derivatives with different electron donating and electron withdrawing groups was investigated using the time-dependent density functional theory. The vertical excitation energies and the electronic structures were explored. Their distinct properties of absorption and fluorescence spectra in solvent phase were explained according to the electronic coupling matrix elements calculated by the Mulliken-Hush theory. The sub-stituent on the oxazolo[4,5-b]pyridines will remarkably change their spectra properties and increase the first excited-state dipole moments. The effect of protonation on the absorption and fluorescence spectra was also investigated systematically. Our study suggests that the present method is feasible to explain charge transfer excitation and predict the properties of absorption and emission spectra in the studied systems.

关 键 词：oxazolo[4 5-b]pyridine spectral properties excited-state charge transfer PROTONATION DFT calculations 

分 类 号：O641.3[理学—物理化学] O626.32[理学—化学]