Department of Chemistry and Bioengineering, Tampere University of Technology, P.O. Box 541, 33101 Tampere, Finland.
J Phys Chem A. 2010 Jul 8;114(26):7094-101. doi: 10.1021/jp9104536.
The fluorescence properties of three pyridylindolizine derivatives (one tricarbomethoxy-7-pyridyl-pyrrolopyridine and two dicarboethoxy-3-bromobenzoyl-7-pyridyl-pyrrolopyridines) have been investigated by applying density functional theory (DFT) and the time-dependent DFT (TDDFT). Performances of two hybrid-type functionals (BH&HLYP and B3LYP) and one generalized gradient approximation (GGA) functional (PBE) as well as three basis sets (SV(P), DZP, and TZVP) have been assessed. The solvent environment has been modeled with the conductor-like screening model (COSMO). Of the three functionals only BH&HLYP is able to yield reasonable estimates for all the studied indolizine derivatives whereas the success of the PBE and B3LYP functionals is highly dependent on the structure of the studied molecule. The SV(P) basis set provides geometrical changes as well as fluorescence maxima and Stokes shifts that agree with those obtained with DZP and TZVP. When a nonpolar solvent is used, COSMO is able to reproduce the experimental fluorescence maxima and Stokes shifts well. However, the agreement between the calculations and experiments is not as good when a solvent with higher polarity is used.
三种吡啶并吲嗪衍生物（一种三羧酸甲酯-7-吡啶基-吡咯并吡啶和两种二羧酸乙酯-3-溴苯甲酰基-7-吡啶基-吡咯并吡啶）的荧光性质已经通过应用密度泛函理论（DFT）和时间相关的密度泛函理论（TDDFT）进行了研究。评估了两种混合类型的泛函（BH&HLYP 和 B3LYP）和一种广义梯度近似（GGA）泛函（PBE）以及三种基组（SV(P)、DZP 和 TZVP）的性能。溶剂环境采用导体相似性屏蔽模型（COSMO）进行建模。在研究的吲嗪衍生物中，只有 BH&HLYP 能够对所有的化合物给出合理的估计，而 PBE 和 B3LYP 泛函的成功高度依赖于所研究分子的结构。SV(P)基组提供了与 DZP 和 TZVP 获得的结果一致的几何变化以及荧光最大值和斯托克斯位移。当使用非极性溶剂时，COSMO 能够很好地重现实验荧光最大值和斯托克斯位移。然而，当使用具有更高极性的溶剂时，计算与实验之间的一致性就不如之前那么好。
