浅谈环张力对C＝C及C＝O双键红外吸收频率的影响

郭艳春, 王慧婷, 魏东辉, 陈晓岚, 曹书霞

Brief Discussion of the Influence of Ring Strain on Infrared Absorption Frequencies of C＝C and C＝O Double Bonds

Yanchun Guo, Huiting Wang, Donghui Wei, Xiaolan Chen, Shuxia Cao

表1 环外C＝C键的振动频率、键长、C＝C键和C―C键的夹角(θ)、轨道成分及张力能计算结果

化合物类型 νC＝C/cm−1 (Calc.) 1669.92 1674.86 1698.24 1781.62 νC＝C/cm−1 (Obs.) 1651 1657 1678 1780 Bond angle (θ)/(°) 122.88 125.80 133.89 148.39 C＝C Bond length/Å 1.336 1.333 1.329 1.322 s character in C＝C/% 37.86 40.09 42.82 47.90 p character in C＝C/% 62.11 59.88 57.15 52.07 Strain energy/(kJ∙mol−1) 0.00 12.92 88.24 127.84