Department of Chemistry, University of Science and Technology Beijing, Beijing 100083, China.
J Phys Chem A. 2010 Feb 4;114(4):1931-8. doi: 10.1021/jp909089x.
Density functional theory (DFT) and time-dependent density functional theory (TDDFT) calculations were carried out to comparatively study the molecular structures, atomic charges, molecular orbitals, and electronic absorption spectra of fluoroboron-subtriazaporphyrin (SubTAP) and fluoroboron-subphthalocyanine (SubPc) as well as their benzo-fused low-symmetrical derivatives A(a)B(b)C(c) (3 > or = a, b, c > or = 0). The peripherally fused benzene rings are revealed to have a significant effect on the structure and charge density distribution of the inner nitrogen atoms of subtriazaporphyrin core, while the charge of the central fluoroboron group changes very little. The effect of peripherally fused benzene rings on the frontier molecular orbitals of different compounds is comparatively discussed. The nature of the electron excitation between the frontier molecular orbitals of the 20 compounds is assigned according to the calculation results. The benzene rings fused directly onto pyrrole rings have been revealed to show more effect on the inner nitrogen atom than the outer benzene rings fused onto the periphery of isoindole rings. The present work will be helpful toward systematically understanding the effect of ring enlargement through asymmetrically fusing benzene ring(s) onto the subtriazaporphyrin skeleton on the structures and properties of fluoroboron-subtriazaporphyrin and fluoroboron-subphthalocyanine analogues.
密度泛函理论（DFT）和含时密度泛函理论（TDDFT）的计算被用来比较研究氟硼取代三嗪卟啉（SubTAP）和氟硼取代酞菁（SubPc）及其苯并稠合的低对称衍生物 A(a)B(b)C(c)（3≥a、b、c≥0）的分子结构、原子电荷、分子轨道和电子吸收光谱。结果表明，外围稠合的苯环对三嗪卟啉核心氮原子的结构和电荷密度分布有显著影响，而中心氟硼基团的电荷变化很小。还讨论了外围稠合苯环对不同化合物前线分子轨道的影响。根据计算结果，对 20 种化合物的前线分子轨道之间的电子激发性质进行了指定。结果表明，直接稠合到吡咯环上的苯环对内部氮原子的影响比稠合到异吲哚环外围上的苯环更大。本工作将有助于系统地理解通过不对称地将苯环（s）稠合到三嗪卟啉骨架上来扩大环对氟硼取代三嗪卟啉和氟硼取代酞菁类似物的结构和性质的影响。
