School of Chemistry and Chemical Engineering, Shanxi University, Taiyuan 030006, PR China.
Spectrochim Acta A Mol Biomol Spectrosc. 2011 Oct 15;81(1):730-8. doi: 10.1016/j.saa.2011.07.017. Epub 2011 Jul 8.
Three new D-π-A type compounds, each containing one benzothiazole ring as an electron acceptor and one N-ethylcarbazole group as electron donor, were synthesized and characterized by elemental analysis, NMR, MS and thermogravimetric analysis. The absorption and emission spectra of three compounds were experimentally determined in several solvents and were simultaneously computed using density functional theory (DFT) and time-dependent density functional theory (TDDFT). The calculated reorganization energy for hole and electron indicates that three compounds are in favor of hole transport than electron transport. The calculated absorption and emission wavelengths are well coincident with the measured data. The calculated lowest-lying absorption spectra can be mainly attributed to intramolecular charge transfer (ICT). And the calculated fluorescence spectra can be mainly described as originating from an excited state with intramolecular charge transfer (ICT) character. The results show that three compounds exhibited excellent thermal stability and high fluorescence quantum yields, indicating their potential applications as excellent optoelectronic material in optical field.
三种新型的 D-π-A 型化合物，每个分子都含有一个苯并噻唑环作为电子受体和一个 N-乙基咔唑基团作为电子给体，通过元素分析、NMR、MS 和热重分析进行了合成和表征。三种化合物的吸收和发射光谱在几种溶剂中进行了实验测定，并同时使用密度泛函理论（DFT）和含时密度泛函理论（TDDFT）进行了计算。计算得到的空穴和电子的重组能表明，三种化合物有利于空穴传输而不是电子传输。计算得到的吸收和发射波长与测量数据很好地吻合。计算得到的最低吸收光谱主要归因于分子内电荷转移（ICT）。并且计算得到的荧光光谱可以主要描述为源于具有分子内电荷转移（ICT）特征的激发态。结果表明，三种化合物表现出优异的热稳定性和高荧光量子产率，表明它们在光学领域作为优秀的光电材料具有潜在的应用。
