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根据分子的共同特征,将彼此紧密关联的分子,区别为三种基本类型,利用对称性分析方法,探求出这三类分子的内旋转势函数的一般公式。应用这些公式到具体分子时,能够非常简捷地写出它们的势函数表达式。利用第一类势函数分析具体问题时,算得的68个分子势垒数值,除少数外,所有计算结果与实验结果的差异均在实验误差范围之内。同时并发现当甲基上的C-H键换成C=C键时,作用能量大为减小;对于具有几个旋转轴的分子,隔开两个以上键间的作用能完全可以忽略。应用第二类势函数,具体联系了五类15个很重要的相关分子,即:CH2Cl-CH2Cl,CHCl2-CHCl2和CHCl2-CH2Cl;CH2F-CH2F,CHF2-CHF2和CHF2-CH2F;CCl2F-CCl2F,CClF2-CClF2和CClF2-CCl2F;CH2(CH3)-CH2(CH3),CH(CH3)2-CH(CH3)2和CH(CH3)2-CH2(CH3)以及C(CH3)2Cl-C(CH3)2Cl,C(CH3)Cl2-C(CH3)Cl2和C(CH3)Cl2-C(CH3)2Cl。理论上得到的结果和实验数据比较有满意的符合,对尚无实验涉及的某些分子的结与性构能,也在理论上作了一些预测。根据第三类势函数,探计了CClFH-CClFH与C(CH3)ClH-C(CH3)ClH两个分子的内旋转;从理论上推测了消式与活性式的内旋转异构体的数目及其构型。Certain molecules, which are intimately related, have been classified into three types according to the general characteristics with respect to the internal rotation. By symmetry analysis of these three types of molecules the general forms of potential functions have been obtained. Applying the results obtained, and the additive property of interaction energies between chemical bonds, we have calculated the potential functions of 85 molecules. All the calculated results agree well with the experimental data. Besides, the number of isomers of internal rotation and the stable configurations in relation to both the meso and the active forms of two molecules CC1FH-CC1FH and C(CH3)C1H-C(CH3)C1H have been predicted .
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