聚对苯撑[poly(p-phenylene)]的基态、极化子和双极化子激发态

GROUND STATE AND POLARON AND BIPOLARON EXCITATIONS IN POLY (P-PHENYLENE)

本文在紧束缚模型基础上,对聚对苯撑类材料提出一简单的哈密顿量,并计算了系统的能带结构,给出基态、极化子、双极化子激发态,得到了双极化子比两个单极化子更容易激发这一重要结论。在能带中除发现能隙内的两个极化子定域能级外,还发现导带和价带都要发生二劈裂,带边上出现浅能级,它们对应的电子态均是定域的。

We have proposed a simple Hamiltonian for poly(p-phenylene) in the framework of SSH tight binding model. The calculations presented to the ground state, polaron and bipolaron show that the formation of doubly charged bipolaron is energetically more favorable than the-formation of two polarons with single, charge. Because the period of the chain is 4a, the CB and VB band will split in two, and when there is a polaron (or bipolaron) in the chain, shallow energe levels will emerge near each band edge besides the polaron (or bipolaron) energe levels, all the corresponding electronic states are localized.