共轭高聚物中的杂质分布:晶格形态及高浓度掺杂效应

Impuritydistribution in conjugated polymers:lattice configuration and heavy doping effect

基于扩展Su-Shrieffer-Heeger(SSH)模型,通过自洽计算的数值方法,研究了共轭高聚物链表现为孤子态和大极化子态两种不同晶格形态时链内的杂质分布情况,计算结果显示,分立的畴壁可导致高聚物链中形成多个稳定的势阱,有利于杂质在链中聚集分布.此外,还研究了在较高浓度的掺杂条件下,共轭高聚物链内的杂质分布规律.结果显示,杂质倾向于在中心区形成高浓度分布,而在链端区,杂质更倾向于离散分布.该研究表明,高浓度掺杂下杂质分布具有稳定的特征,晶格形态对杂质分布具有显著的影响,这些结论可为实验上操控杂质在共轭高聚物中的分布提供一定的帮助.

Based on the extended Su-Shrieffer-Heeger （SSH） model,we investigate the impurity distribution in 1D conjugated polymer chains with two different lattice configurations,soliton and bipolaron.The results show that the separated domain walls favor multi-stable states in a conjugated polymer chain.These states help impurities get to cluster in polymers.In addition,we also studied the impurity distribution in a conjugated polymer chain under heavy doping condition.The results show that the heavy doping can occur only within the center region.While in the edge region,impurities incline to distribute discretely.This study indicates that the impurity distribution in the case of heavy doping has steady characteristic and the lattice configuration has evident impact on impurity distribution.These results will be a great help for experimentally controlling impurity doping in conjugated polymers.