苯甲酸分子表面增强拉曼光谱的密度泛函理论研究

摘要

基于密度泛函理论,利用量子化学软件,在B3LYP/6-311G** (C,H,S)/Lan12dz (Ag)水平上对苯甲酸(Benzoic Acid,C7H6O2,BA)进行几何优化,得到BA与Ag原子和Ag离子结合,即C7H5O2-Ag和C7H5O2Ag的平衡构型,在此基础上得到了两种形态的计算拉曼谱图,并和其他文献值进行比较,其中C7H5O2Ag的计算结果与文献中的BA表面增强拉曼光谱的实验值符合得较好.同时采用简正振动分析方法得到其势能分布,从而对其简正振动模式进行了全面归属.%In the present paper,DFT method at the B3LYP/6-311G** (C,H,S)/Lan12dz (Ag) level was used to optimize molecular configurations of benzoic acid (BA).The optimized geometries and calculated Raman spectra of the complexes C7H5O2-Ag and C7 H5 O2 Ag were obtained.The calculated Raman spectrum of C7H5O2Ag is in good agreement with the surface-enhanced Raman spectrum experimental results of other literatures values.The potential energy distribution of BA adsorbed on Ag was calculated on the basis of the optimized structure and vibrational analysis.We made the assignments of all the fundamentals.