Theoretical Insights into the Substituent Effects on the Fluorescence of Boron Complexes of 2-(Benzothiazol-2-yl)phenols: a Quantum Mechanics Study  

作　　者：LI Hui-Xue WANG Xiao-Feng ZHU Yuan-Cheng YUAN Kun LV Ling-Ling LI Zhi-Feng 李会学;王晓峰;朱元成;袁焜;吕玲玲;李志锋(School of Chemical Engineering and Technology,Tianshui Normal University,Tianshui 741001,China)

机构地区：[1]School of Chemical Engineering and Technology,Tianshui Normal University,Tianshui 741001,China

出　　处：《Chinese Journal of Structural Chemistry》2020年第2期243-254,184,共13页结构化学（英文）

基　　金：supported by the Natural Science Foundation of China(No.21463023);the Project of the Beijing National Laboratory for Molecular Sciences(BNLMS20160155);the Research Funding of Gansu Provincial Department of Education(2016B-072);the Key Project of Tianshui Normal University(TSA1501)。

摘　　要：The performance of organic fluorescent materials can be improved by chemical substitutions with auxochrome groups such as amino to increase solubility, alter emitting color, or modify film quality. The complex 6,6-difluoro-6-bora-5-oxa-11-thia-6 a-aza-benzo[a]fluorine(BOBTP) and its derivatives, which possess excellent luminescent property at room temperature, were theoretically simulated by density functional theory. The geometries of the ground state and the first excited state of BOBTPs complexes were investigated and their bond parameters were obtained. Further, these bond parameters are compared with each other, and the computational wavelengths of maximum absorption and emission of studied complexes match up with the experimental values. It was found that amino substituent bonding to appropriate positions of BOBTP can reduce the reorganization energy significantly, which is ascribed to electron-donating effect of the amino group. The reorganization energy also plays an important role in the fluorescence quantum yield of all the BOBTPs. In particular, the radiative decay of complexes 3 and 4 is dominant due to the smaller reorganization energies, so their fluorescence quantum yield is almost 1, on the contrary the non-radiative decay and intersystem crossing rate of both the 1 and 2 can not be ignored for the larger reorganization energies, and the corresponding fluorescence quantum yields were calculated when the radiative decay rate(kr) and nonradiative decay rate(k(nr)) were taken into account.

关 键 词：THEORETICAL STUDY FLUORESCENCE spectrum BOBTPs SUBSTITUENT effects 

分 类 号：O641.4[理学—物理化学] O657.3[理学—化学]