Department of Chemistry, Kanchi Mamunivar Centre for Post-Graduate Studies, Puducherry, India.
Spectrochim Acta A Mol Biomol Spectrosc. 2011 May;78(5):1625-32. doi: 10.1016/j.saa.2011.02.018. Epub 2011 Feb 13.
The Fourier transform infrared (FTIR) and FT-Raman spectra of 2-chloro-6-methoxypyridine have been recorded in the range 3700-400 and 3700-100 cm(-1), respectively. The complete vibrational assignment and analysis of the fundamental modes of the compound was carried out using the observed FTIR and FT-Raman data. The vibrational frequencies determined experimentally were compared with the theoretical frequencies computed by DFT gradient calculations (B3LYP method) employing the 6-31G(d,p), cc-pVTZ and/6-311++G(d,p) basis sets for the optimised geometry of the compound. The geometry and normal modes of vibration obtained from the DFT methods are in good agreement with the experimental data. The normal co-ordinate analysis was also carried out using DFT force fields utilising Wilson's FG matrix method. The influence of the substituents bulky chlorine atom and the methoxy group on the spectral characteristics of the compound has been discussed. The electronic spectrum determined by TD-DFT method is compared with the observed electronic spectrum.
已记录下 2-氯-6-甲氧基吡啶在 3700-400 和 3700-100 cm(-1) 范围内的傅里叶变换红外（FTIR）和 FT-Raman 光谱。使用观察到的 FTIR 和 FT-Raman 数据，对该化合物的基本模式的完整振动分配和分析进行了研究。通过 DFT 梯度计算（B3LYP 方法），使用 6-31G(d,p)、cc-pVTZ 和/6-311++G(d,p)基组对化合物的优化几何结构进行了理论频率的计算，实验确定的振动频率与理论频率进行了比较。从 DFT 方法获得的几何形状和振动模式与实验数据非常吻合。还使用 DFT 力场，通过 Wilson 的 FG 矩阵方法进行了正则坐标分析。讨论了取代基大体积氯原子和甲氧基对化合物光谱特征的影响。通过 TD-DFT 方法确定的电子光谱与观察到的电子光谱进行了比较。
