聚酰亚胺几何结构和电子结构的分子模拟

The Molecular Simulation of Electronic and Geometry Structure of Polyimide

依据密度泛函(DFT)理论,利用PW 91方法,对聚酰亚胺二、三和四聚体进行模拟,研究其几何结构和电子结构.模拟结果表明,聚酰亚胺二、三和四聚体中间片断的键长、键角基本一致,采用低聚物中间片断结构,可以表征整个高分子聚合物结构,随着聚合度N的增加,总能量降低,能隙减小.

According to DFT theory, the electronic structures of polyimide （ N =2,3,4） are simulated by using PW1 method. The geometry structure and electronic structure of polyimide molecules are studied. The results show that the middle structures of polyimide （N = 2,3,4） are consistent, it is proved that using middle structure of low polymer to describe the structure of high polymer is feasible, and with N increasing, total energy descends and the energy gap diminishes.