Sarkar Jyotirmoy, Chowdhury Joydeep, Ghosh Manash, De Rina, Talapatra G B
Department of Spectroscopy, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700 032, India.
J Phys Chem B. 2005 Dec 1;109(47):22536-44. doi: 10.1021/jp054501o.
The adsorption of 2-amino-4-methylbenzothiazole (2-AMBT) on colloidal silver particles has been investigated by a surface enhanced Raman scattering (SERS) study. The SERS spectra of the 2-AMBT molecule at varied adsorbate concentrations recorded in different time domains are compared with its Fourier transform infrared (FTIR) spectrum and normal Raman spectrum (NRS) in the bulk and in solution. The experimentally observed SERS spectra are compared with the theoretically modeled surface complexes using ab initio restricted Hatree-Fock (RHF) and density functional theory (DFT) calculations. The most favorable adsorptive sites of the 2-AMBT molecule have been estimated by natural population analysis (NPA) using the above-mentioned high level of theories. The enhancement of the in-plane modes together with the appearance of Ag-N stretching frequency at 215 cm(-1) indicates that the 2-AMBT molecule is adsorbed on the silver surface through the lone pair electrons of both nitrogen atoms with the molecular plane nearly vertical to the surface.
通过表面增强拉曼散射（SERS）研究，对2-氨基-4-甲基苯并噻唑（2-AMBT）在胶体银颗粒上的吸附进行了研究。将在不同时域记录的不同吸附质浓度下2-AMBT分子的SERS光谱与其在本体和溶液中的傅里叶变换红外（FTIR）光谱和正常拉曼光谱（NRS）进行比较。使用从头算受限哈特里-福克（RHF）和密度泛函理论（DFT）计算，将实验观察到的SERS光谱与理论建模的表面配合物进行比较。使用上述高水平理论，通过自然布居分析（NPA）估计了2-AMBT分子最有利的吸附位点。面内模式的增强以及215 cm(-1)处Ag-N伸缩频率的出现表明，2-AMBT分子通过两个氮原子的孤对电子吸附在银表面，分子平面几乎垂直于表面。
