基于密度泛函理论的尼克酸分子振动光谱分析

Analysis of Vibrational Spectra of Niacin Based on Density Functional Theory

实验测量了尼克酸分子的拉曼和红外光谱,用B3LYP混合泛函和cc-PVDZ基组计算了尼克酸分子的平衡构型、振动频率、拉曼和红外强度。采用GAR2PED程序对尼克酸分子进行了简正振动分析,依据所得势能分布对尼克酸分子的振动频率进行了理论归属,弥补了以往文献缺少对其振动模式贡献进行定量研究的不足,提供了更多的振动光谱信息。

The Raman and infrared spectra of niacin were measured experimentally.The molecular equilibrium geometries,vibrational frequencies,Raman and infrared intensity of niacin were calculated using the B3 LYP level and cc-PVDZ basis set.Normal mode analysis was carried out using the program GAR2 PED and the assignment of fundamental vibrations for niacin was obtained according to the potential energy distributions（PED）.This study provides us with more quantitative vibrational spectral information which was not mentioned in previous literatures.