This account reviews the current development of extraordinarily long oligothiophenes involving the 48-mer and 72-mer, which correspond to mono-disperse polymers. The systematic studies of the homologous series have provided valuable information on the optical and conductive properties of α-conjugated thiophene systems: an effective conjugation length extends to around 20 thiophene units in the neutral state and around 30 thiophene units in the oxidation state; this length plays a critical role in determining the electronic structures and conductivities. In addition, the active charge carrier species are both π-dimers and chain dimers, and charge transport occurs through the transfiguration of both species. This account also describes how useful oligothiophenes are as molecular wires allowing photoinduced electron- and/or energy-transfer. The molecular-wire behaviors of sophisticated oligothiophenes that are functionalized with a donor unit and an acceptor unit at the terminal α-positions are demonstrated.
本报告回顾了涉及 48 聚体和 72 聚体(对应于单分散聚合物)的超长低聚
噻吩的当前发展。同系物的系统研究为α-共轭
噻吩体系的光学和导电性质提供了有价值的信息:有效共轭长度在中性态下延伸至约20个
噻吩单元,在氧化态下延伸至约30个
噻吩单元;这个长度在确定电子结构和电导率方面起着至关重要的作用。此外,活性电荷载体物种都是π-二聚体和链二聚体,并且电荷传输通过这两种物种的变形发生。该描述还描述了低聚
噻吩作为允许光诱导电子和/或能量转移的分子线是多么有用。演示了在末端 α-位置用供体单元和受体单元功能化的复杂低聚
噻吩的分子线行为。