采用密度泛函理论(density functional theory, DFT)， 在B3LYP/6-31++G**(C， H， N， S)/LANL2DZ(Ag)水平上， 对对巯基苯胺(p-aminothiophenol, PATP)分子进行了几何结构优化， 计算了PATP的常规拉曼散射(normal Raman scattering, NRS)光谱和PATP与Ag原子以及Ag2团簇吸附的表面增强拉曼散射(surface-enhanced Raman scattering, SERS)光谱， 并和其他文献值进行比较。 计算表明， 计算结果与已有的实验值符合得较好， 采用PATP—Ag2吸附构型比PATP—Ag吸附构型的计算结果更符合已有实验值。 最后， 通过GaussView可视化软件， 对PATP分子的振动频率进行了更为全面地归属。 通过PATP分子SERS与NRS的比较， SERS在213 cm-1处观察到明显的Ag—S伸缩振动谱带， 可以说明PATP分子是通过形成Ag—S化学键吸附在银纳米粒子上的。 该工作对理解和解释一些实验现象具有重要的指导意义， 同时也为研究PATP分子的SERS增强机理打下了基础。

In the present paper, DFT method at the B3LYP/6-31++G**(C， H， N， S)/LANL2DZ(Ag) level was used to optimize molecular configurations of p-aminothiophenol. Based on the optimized structure, the normal Raman scattering(NRS) spectrum of PATP and the surface-enhanced Raman scattering(SERS)spectrum of PATP adsorbed on Ag and Ag2 were both calculated, and were compared with the results of other literatures values. The calculation results indicated that a good conformity was found between the computed and experimental results. The results of PATP adsorbed on Ag2 were more approximate to the ever reported experimental data than those of PATP adsorbed on Ag. At the end, detailed analysis of the Raman spectrum and more comprehensive assignments of the vibration mode for p-aminothiophenol were studied by the software of GaussView. In comparison with SERS spectrum and NRS spectrum of PATP molecule, the authors observed the stretching vibration bands in the SERS spectrum at about 213 cm-1, which is due to Ag—S stretching vibration mode. The work in this paper has greatly directive value in understanding and explaining some experiment phenomenon, and helps to study the mechanism of surface-enhanced Raman scattering of PATP.