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

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.