电子关联对顺式聚乙炔中双极化子附近局域振动模的影响

EFFECTS OF e-e INTERACTION ON THE LOCALIZED MODES OF cig-(CH)x AROUND A BI-POLARON

用自洽迭代的方法研究了顺式聚乙炔中双极化子的能谱及其附近的局域振动模.结果发现:1)在顺式聚乙炔中,双极化子的电子束缚态数目和位置仅取决于耦台参数λ和电子相互作用U,这类似于反式聚乙炔;参数t_l(消除基态二度简并)虽不能改变电子局域态的个数,但影响了双极化子附近局域模的数目.2)电子相互作用不仅使局域模的频率发生了漂移,而且增加了局域模的个数,这不同于反式,3)局域模的局域性随耦合参数λ以及电子相互作用U的增加而增强,随参数(?)的增大而减弱.

We have studied the energy spectra of bi-polaron and the localized modes around a bi-polaron in cis-(CH), by using a self-consistent approach. The results show that: 1) The number of the electronic bound states and their locations only depend on the coupling constant λ and e-e interaction r as in the case of trans-(CH)x; 2) e-e interaction not only causes the shifts of the frequencies of localized modes and strengthening of their localizations, but also increases the number of localized modes, in which cis-(CH)x differs from trans-(CH)x; 3) The number of localized mo- < des are decreased and the localizations are weakened when parameter t2 (removing the degeneracy of the ground state) increases.