态定(线性响应)-极化连续模型/含时密度泛函方法研究一种有机发光材料的吸收和发射光谱(英文)

State-Specific(Linear-Response)-Polarizable Continuum Models/Time-Dependent Density Functional Theory Study on the Absorption and Emission Spectra of an Organic Fluorescent Emitter

3-(二氰亚甲基)-5,5-二甲基-1-(3-[9-(2-乙基-己基)-咔唑基]-乙烯基)环己烷(DCDHCC)是一种用于光电器件中的有机染料,它具有良好的发光特性.我们使用含时密度泛函方法(TD-PBE0,TD-BMK和TD-M06)以及极化连续模型(PCM)计算了该材料在溶剂中的吸收和发射特性.计算中使用了线性响应(LR)、态定(SS)两种溶剂模型和6-31G(d)、6-31+G(d,p)两种基组.计算了DCDHCC在苯、四氢呋喃和丙酮溶剂中的吸收和发射光谱,并与实验观测进行了比较.结果表明:对于吸收光谱的计算,杂化函数的影响大于基组和溶剂模型,在三种函数中BMK更适于研究DCDHCC的吸收光谱;而对于发射光谱,基组的影响最大,基组通过影响激发态构型从而影响发射光谱,对于激发态构型的优化需要使用6-31+G(d,p)基组.我们希望这些研究能对今后设计类似的发光分子有帮助.

3-（dicyanomethylene）-5,5-dimethyl-1-（3-[9-（2-ethyl-hexyl）-carbazol]-vinyl） cyclohexene（DCDHCC） is one of a series of organic dyes with good emission performance in photoelectric devices.The absorption and emission spectra of DCDHCC were computed using PBE0,BMK,and M06 hybrids in the frame of time-dependent density functional theory（TDDFT） in combination with polarizable continuum models（PCMs）.Linear-response（LR） and state-specific（SS） PCM approaches were used as well as 6-31G（d） and 6-31＋G（d,p） basis sets.The absorption and emission spectra were calculated in benzene,tetrahydrofuran,and acetone and compared with experimental observations.On the one hand,choice of hybrids was found to have a greater effect on the absorption spectra than the basis sets or the solvent model and BMK was established to be a suitable functional for the calculation of the absorption spectra of DCDHCC,on the other hand,the basis set used had a significant impact on the geometries of the excited states and thus the emission spectra,and the 6-31＋G（d,p） basis set was necessary for the optimization of the excited states.It is envisaged that our calculations may be of assistance in the design of analogous emitters.