Time-dependent density functional theory (TD-DFT) calculations are performed to systematically investigate the absorption and emission properties of α-oligothiophenes taking into account of various functionals, basis sets and bulk solvent effects. The effects of different functionals on the optical properties are investigated employing global and meta hybrid functionals B3LYP, M06 and also with range separated hybrid functionals like ωB97XD and CAM-B3LYP. The results are further assessed to test their validity against the available experimental data. The bulk solvent effects are introduced by the linear response (LR) and the state specific (SS) models in the framework of the polarizable continuum model (PCM). Pople type of basis sets has been employed and the role of inclusion of polarized and diffused functions in the basis sets in determining the optical properties is investigated. The long-range correction scheme in CAM-B3LYP is found to produce accurate results for the excitation energies very much in agreement with the experimental data.

进行时变密度泛函理论（TD-DFT）计算以系统地研究α-低聚噻吩的吸收和发射性质，同时考虑到各种泛函，基集和整体溶剂效应。使用全局和间混合功能B3LYP，M06以及范围分离的混合功能（如ωB97XD和CAM-B3LYP），研究了不同功能对光学性能的影响。进一步评估结果，以根据可用的实验数据测试其有效性。在可极化连续体模型（PCM）的框架内，线性响应（LR）模型和状态特定（SS）模型引入了整体溶剂效应。已经使用了Pople类型的基集，并研究了在确定光学性质的基础集中包含极化和扩散函数的作用。发现CAM-B3LYP中的远程校正方案可以非常准确地得出激发能量的结果，与实验数据相符。