齐分子噻吩的中性态和掺杂态的几何结构特性

Study on the Geometric Properties of Neutral and Charged States of Oligothiophenes

采用半经验的AustinModel1(AM1)方法 ,计算了齐分子噻吩聚合物的中性态和带电态的几何结构性质 .与中性态相比 ,带电态下其分子结构表现在C -C键键长发生显著改变 ,单电荷掺杂导致极化子元激发 ;双电荷掺杂产生双极化子 ,即使增加链长至 16PT ,仍在链中产生双极化子而不是两个分立的单极化子 ;掺杂 4个电荷时 ,会在聚合物链中产生两个分离的双极化子 .

The results of the Austin-Model 1 (AM1) geometry optimization calculations are present to determine the neutral and charged geometry properties of oligothiophenes. Comparing with the neutral states, the changes of the bond lengths of the charged states are very evident. The singly oxidized state is corresponding to polaron and the doubly oxidized state to bipolaron. The bipolarons are always more stable than the polarons even if the chain length is 16 PT. The quadruple oxidized state is corresponding to two separate bipolarons.