基于DFT的间羟基苯甲酸分子表面增强拉曼光谱研究

摘要

In this paper,both Normal Raman Scattering (NRS) spectroscopy and the Surface-enhanced Raman Scattering (SERS) spectroscopy that adsorbed on silver nanoparticles of m-hydroxybenzoic acid (MHBA) were researched.At the B3LYP/6-31+G**(C、H、O)/LANL2DZ(Ag)level,Density Functional Theory(DFT)method was used to optimize molecular configurations of MHBA.Based on optimized structure,the NRS spectroscopy and the SERS spectroscopy by different adsorption configurations of MHBA had been calculated all.Compared with the experimental data,the calculation results using MHBA molecular adsorption configuration through both carboxyl and hydroxyl groups were much more matched with experimental values than those of through carboxyl.At the end,comprehensive assignments of the vibration mode for MHBA were studied by the software of GaussView.%本文研究了间羟基苯甲酸(m-hydroxybenzoic acid,MHBA)的常规拉曼散射(normal Raman scattering,NRS)光谱及其吸附在Ag纳米颗粒上的表面增强拉曼散射(surface-enhanced Raman scattering,SERS)光谱.采用密度泛函理论(density functional theory,DFT),在B3LYP/6-31+G**(C、H、O)/LANL2DZ(Ag)水平上,对MHBA分子进行了几何结构优化,在此基础上计算了MHBA分子的NRS光谱以及其吸附在Ag纳米颗粒上两种不同吸附构型下的SERS光谱,并和实验值进行比较.结果表明,间羟基苯甲酸分子通过羧基与羟基共同吸附构型的计算结果比该分子通过羧基吸附构型的计算结果更符合实验值.最后,利用GaussView可视化软件对其振动模式进行了全面归属.