Rastogi V K, Alcolea Palafox M, Tanwar R P, Mittal Lalit
Physics Department, CCS University, Merrut, India.
Spectrochim Acta A Mol Biomol Spectrosc. 2002 Jul;58(9):1987-2004. doi: 10.1016/s1386-1425(01)00650-3.
Geometry, vibrational wavenumbers and several thermodynamic parameters were calculated using ab initio quantum chemical methods for the 3,5-difluorobenzonitrile molecule. The results were compared with the experimental values. With the help of three specific scaling procedures, the observed vibrational wavenumbers in FTIR and Raman spectra were analysed and assigned to different normal modes of the molecule. Most of the modes have wavenumbers in the expected range and the error obtained was in general very low. Using PEDs the contributions were determined for the different modes to each wavenumber. From the PED, it is apparent that the frequency corresponding to C[triple bond]N stretching contains 87% contribution from the C[triple bond]N stretching force constant and it mixes with the C-CN stretching mode 13 to the extent of 12%. Other general conclusions were also deduced.
使用从头算量子化学方法计算了3,5-二氟苯腈分子的几何结构、振动波数和几个热力学参数。将结果与实验值进行了比较。借助三种特定的标度程序，对傅里叶变换红外光谱（FTIR）和拉曼光谱中观察到的振动波数进行了分析，并将其指定为该分子的不同简正模式。大多数模式的波数在预期范围内，得到的误差总体上非常低。使用势能分布（PEDs）确定了不同模式对每个波数的贡献。从PED可以明显看出，对应于C≡N伸缩的频率中，C≡N伸缩力常数的贡献占87%，并且它与C-CN伸缩模式13混合的程度为12%。还得出了其他一般性结论。
