Chemistry Department, Faculty of Science, King Khalid University, Abha, Saudi Arabia.
J Mol Model. 2012 Sep;18(9):4199-207. doi: 10.1007/s00894-012-1421-4. Epub 2012 May 4.
Zinc tetraphenylporphyrin (ZnTPP) was modified by a push-pull strategy and then density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations were performed for the resulting derivatives. The smallest HOMO-LUMO energy gaps were found in ZnTPP-6 and ZnTPP-7, which had nitro substituents and a conjugated chain, while the largest was observed for ZnTPP-5. The energy gaps of all of the systems designed in this work were smaller than that of ZnTPP. Clear intramolecular charge transfer was observed from donor to acceptor in ZnTPP-6 and ZnTPP-7, which had nitro groups at positions R8, R9, and R10, as well as in ZnTPP-3 and ZnTPP-4, which had cyano groups at those positions. The narrow band gaps (compared to that of ZnTPP) of these designed systems, where the LUMO is above the conduction band of TiO(2) and the HOMO is below the redox couple, indicate that they are efficient sensitizers. The B bands of these newly designed derivatives, except for ZnTPP-5, are redshifted compared with the B band of ZnTPP.
锌四苯基卟啉（ZnTPP）采用推-拉策略进行修饰，然后对得到的衍生物进行了密度泛函理论（DFT）和含时密度泛函理论（TD-DFT）计算。在具有硝基取代基和共轭链的 ZnTPP-6 和 ZnTPP-7 中，最小的 HOMO-LUMO 能隙，而 ZnTPP-5 则具有最大的能隙。本工作设计的所有体系的能隙均小于 ZnTPP。在具有 R8、R9 和 R10 位硝基取代基的 ZnTPP-6 和 ZnTPP-7 以及具有这些位置氰基取代基的 ZnTPP-3 和 ZnTPP-4 中，观察到从给体到受体的明显的分子内电荷转移。这些设计的体系的窄带隙（与 ZnTPP 相比），其中 LUMO 高于 TiO(2)的导带，HOMO 低于氧化还原对，表明它们是有效的敏化剂。与 ZnTPP 的 B 带相比，除了 ZnTPP-5 之外，这些新设计的衍生物的 B 带都发生了红移。
