儿茶素结构和振动光谱的密度泛函理论研究

Density functional theory study on structure and vibrational spectra of catechins

本文利用密度泛函理论方法B3LYP在6-311+G(d,p)水平上研究了儿茶素及其异构体表儿茶素分子的几何构型,计算结果与实验所得结构参数一致。计算了儿茶素分子平衡构型下的力常数,使用Wilson的GF矩阵方法计算了振动基频以及相应的势能分布,据此结合理论计算的光谱强度,对儿茶素分子的振动基频进行了完善合理的理论归属。

In the present study,density functional theory method （B3LYP/6-311 ＋ G ＊ ＊ ） was performed to study the optimized molecular structure of （ ＋ ）-catechin and （-）-epicatechin. On the basis of optimized structure, the harmonic fields, vibrational frequencies and infrared intensities were calculated. A normal coordinate analysis was carried out using B3LYP/ 6-311 ＋ G ＊ ＊ force field with GF matrix method developed by Wilson. The assignment of fundamental vibrations for （ ＋ ） -catechin was performed according to the potential energy distributions.