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本文对分子内旋转问题作了以下的贡献:首先在理论上,提供了一种分子内旋转势函数的新的计算方法。这种新方法不仅理论上来得谨严,避免了以往旧方法中的一些缺点,而且比较简单,应用范围也因此比较广泛。其次,应用这种方法到一些具体问题,得到了下列结果:1.严格的得到了 Pitzer 方程,并估计了它的准确程度。2.证明了 CX_2Y-CX_2Y、CY_2X-CY_2X 和 CX_2Y-CXY_2内旋转势函数间的连系性,设第一种分子的势函数为V_1(φ)=A_1+B cosφ+C cos 2φ+D_1 cos 3φ第二和第三两种分子的势函数分别为V_2(φ)=A_2+B cosφ+C cos 2φ+D_2 cos 3φ和V_3(φ)=A_3-B cosφ-C cos 2φ+D_3 cos 3φ具体讨论了两类很重要的相关的分子:一类是 CH_2Cl—CH_2Cl、CHCl_2—CHCl_2和CHCl_2—CH_2Cl,另一类是 CH_2(CH_3)—CH_2(CH_3)、CH(CH_3)_2—CH(CH_3)_2和CH_2(CH_3)—CH(CH_3)_2。理论上得到的结果和实验全都符合。3.批判了以往一些人建议的乙醇的内旋转势函数经验式,从理论上提出了乙醇势函数的正确形式,并推断了乙醇的内旋转异构体。4.由内旋转势函数推得过氧化氢的结构,并推得联氨的可能结构,和实验结果相符合。并提供了一种实验方法,来判断联氨分子中的——因此也就是氨分子中的氮原子上独对电子的性格,是 s 还是 sp~3,或者接近于哪一种。 5.讨论了 CXYZ-CXYZ 内旋消式和活性式的内旋转问题,证明了它们的内旋转势函数,和 CX_2Y-CX_2Y、CY_2Z-CY_2Z 以及 CZ_2X-CZ_2X 的密切相关联。知道了后三者的势函数,前者的也就立刻可以计算。同时推测了 CXYZ-CXYZ内旋消式有两种内旋转异构体,活性式有三种,都以对位结构为最稳定。根据我们所讨论的,可以很清楚地看出:Pitzer 和 Crawford 等人所造的计算表已经不够用了。为了使得分子内旋转问题很好的向前发展,需要造一种以V_(φ)=A+B cosφ+C cos 2φ+D cos 3φ为内旋转势函数的计算表。
In this paper, we make the following contributions to the intramolecular rotation problem: Firstly, in theory, we provide a new calculation method for the intramolecular rotation potential function. This new method is not only cautious in theory, avoiding some of the shortcomings of the old methods in the past, but also simpler and more extensive in application. Secondly, applying this method to some specific problems, the following results are obtained: 1. The Pitzer equation is strictly obtained and its accuracy is estimated. It is proved that the potential function of the first kind of molecule is V_1 (φ) = A_1 + B cosφ + C cos 2φ + D_1 cos 3φ The potential functions of the second and third molecules are respectively V_2 (φ) = A_2 + B cosφ + C cos 2φ + D_2 cos 3φ and V_3 (φ) = A_3-B cosφ-C cos 2φ + D_3 cos 3φ Two classes of important related molecules are discussed: one is CH 2 Cl-CH 2 Cl, CHCl 2-CHCl 2 and CHCl 2-CH 2 Cl and the other is CH 2 CH 3 -CH 2 CH 3 CH 3 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 2 CH 3 CH 2 CH CH 3 CH _2 and CH_2 (CH_3) -CH (CH_3) _2. Theoretically obtained results and experiments are all consistent. 3. Criticism of some people’s previous empirical formula for the internal rotation potential of ethanol suggested the correct form of the ethanol potential function theoretically and deduced the internal rotation isomers of ethanol. The structure of hydrogen peroxide is deduced from the internal rotation potential function, and the possible structure of hydrazine is deduced, which is consistent with the experimental results. And provides an experimental method to determine which of the satellites, which is s or sp ~ 3, or which one is closer to, in the hydrazine molecule - and thus the nitrogen atom in the ammonia molecule. The internal rotation of CXYZ-CXYZ and the internal rotation of CXYZ-CXYZ are discussed, and their internal rotation potential functions are proved to be closely related to CX_2Y-CX_2Y, CY_2Z-CY_2Z and CZ_2X-CZ_2X. Know the potential function of the latter three, the former can be calculated immediately. At the same time, it is speculated that there are two kinds of internal rotamers in CXYZ-CXYZ. There are three types of active rotors, all of which are the most stable in para-position. From what we have discussed, it is clear that the calculators made by Pitzer and Crawford were not enough. In order to make the intramolecular rotation problem move forward well, we need to make a calculation table that takes V_ (φ) = A + B cosφ + C cos 2φ + D cos 3φ as the internal rotation potential function.