Department of Chemistry, Kanchi Mamunivar Centre for Post-Graduate Studies, Puducherry, India.
Spectrochim Acta A Mol Biomol Spectrosc. 2012 Jun 15;92:1-15. doi: 10.1016/j.saa.2012.02.029. Epub 2012 Feb 20.
The Fourier transform infrared (FTIR) and FT-Raman spectra of α,α'-diol-o-xylene (DOLOX), α,α'-diol-m-xylene (DOLMX) and α,α'-diol-p-xylene (DOLPX) of the configuration HOCH(2)-C(6)H(4)-CH(2)OH have been recorded in the range 4000-400 and 4000-100 cm(-1), respectively. The most stable geometry of the compounds was determined by conformational analysis. The complete vibrational assignment and analysis of the fundamental modes of the most stable conformer of the compounds were carried out using the experimental FTIR and FT-Raman data and quantum chemical studies. The observed vibrational frequencies were compared with the wavenumbers derived theoretically for the optimised geometry of the compounds from the DFT-B3LYP gradient calculations employing the standard 6-31G** and high level and 6-311++G** basis sets. The structural parameters and vibrational wavenumbers obtained from the DFT method are in good agreement with the experimental data. The potential energy distributions of the fundamental modes were also calculated by Wilson's FG matrix method. The effect of -CH(2)OH groups on the skeletal vibrations have been discussed. The intra molecular n→σ* and π→π* interactions were discussed with NBO analysis.
α,α'-二醇邻二甲苯（DOLOX）、α,α'-二醇间二甲苯（DOLMX）和α,α'-二醇对二甲苯（DOLPX）的傅里叶变换红外（FTIR）和 FT-Raman 光谱在 4000-400 和 4000-100 cm(-1) 范围内分别记录。通过构象分析确定了化合物的最稳定几何形状。利用实验的 FTIR 和 FT-Raman 数据以及量子化学研究，对化合物最稳定构象的基本振动模式进行了完整的振动归属和分析。观察到的振动频率与从 DFT-B3LYP 梯度计算中为化合物优化几何形状推导出的理论波数进行了比较，使用了标准 6-31G和高级 6-311++G基组。从 DFT 方法获得的结构参数和振动波数与实验数据吻合良好。还通过 Wilson 的 FG 矩阵方法计算了基本模式的势能分布。讨论了-CH(2)OH 基团对骨架振动的影响。通过 NBO 分析讨论了 n→σ和π→π 相互作用。
