导电高分子能带的Wannier函数方法

Wannier-Function Method of Energy Bands for Conducting Polymers

导电高分子的Peierls不稳定性会在费米面上产生能隙,它将半满能带分裂成价带和导带,并使体系变为半导体.本文给出了在二聚化的基础上利用Wannier函数来计算导电高分子能带的一般方法,由此可改进紧束缚近似下的SSH 模型.我们把这一方法应用于聚乙炔链并采用二聚化的一维方势阱模型,其结果是极为令人满意的.

The Peierls instability of conducting polymers opens a gap at the Fermi surface, and thehalf filled band is split into a valence band and a conduction band, and the system becomes asemiconductor.This paper gives a general method in which the dimerized Wannier Function isused to calculate the bands of conducting polymers,and the tight-binding SSH model can beimproved.We apply the method to polyacetylene chain and employ the one-dimensionalsquare well of dimerization, the results are very satisfactory.