Tuning the Electronic Properties of Nonplanar exTTF-Based Push–Pull Chromophores by Aryl Substitution
作者:Raúl García、M Ángeles Herranz、M Rosario Torres、Pierre-Antoine Bouit、Juan Luis Delgado、Joaquín Calbo、Pedro M. Viruela、Enrique Ortí、Nazario Martín
DOI:10.1021/jo302047m
日期:2012.12.7
largely increases the optical band gap. An effective electronic communication between the donor and acceptor units, although limited by the distorted molecular geometry, is evidenced both in the ground and in the excited electronic states. The electronic absorption spectra are characterized by low- to medium-intense charge-transfer bands that extend to the near-infrared.
通过[2 + 2] TCNE与exTTF取代的炔烃的环加成反应,合成了一个新的π扩展的四硫富富瓦烯(exTTF)供体-受体生色团。在B3LYP / 6-31G **水平上进行的X射线数据和理论计算表明,新的生色团表现出高度扭曲的非平面分子结构,并带有大量扭曲的1,1,4,4-tetracyanobuta-1,3-diene( TCBD)单位。当TCBD受体单元被供体苯基取代时,通过紫外/可见光谱和电化学测量研究的电子和光学性质会显着改变,这会增加TCBD单元的扭曲并减少两个双氰基乙烯基亚基之间的共轭。苯基取代基的引入阻碍了氧化和还原过程,同时,大大增加了光学带隙。供体和受体单元之间的有效电子通信,尽管受到扭曲的分子几何形状的限制,但在地面和激发电子态中都得到了证明。电子吸收光谱的特征是延伸到近红外的低至中强度的电荷转移带。