摘要
在分子转动模型基础上 ,以半经验分子轨道 (AM1)方法计算分子的转动惯量及其它结构参数 ,获得 15个正烷烃的沸点和熔点的多元线性回归方程。其中正烷烃的沸点与短轴转动惯量 (c)和碳原子数 (n)相关 (bp =- 147 2 - 0 0 1189c+ 36 17n ,R =0 9985,SD =6 97) ,而熔点与分子的长轴转动惯量 (a)、短轴转动惯量 (b,c)及重定向能 (E)相关 (mp =- 2 6 0 3+ 15 70a + 19 74b - 19 76c +1 30E ,R =0 99991,SD =1 0 7)。分子的长轴转动惯量和重定向能与正烷烃熔点的奇
The boiling points and melting points of 15 n -alkanes (carbon number 2~16) were predicted multiple linear regression based on the molecular structural parameters with molecular rotation model. The rotation inertia of molecular short axis are responsible for the boiling points (bp= -147 2 -0 01189c+36 17n with R=0 9985 and SD=6 97), but the rotational inertia in long molecular axis and reorientation energy are responsible for the sawtooth behavior of melting points of n- alkanes. The multiple regression equation of four factors including rotational inertia in three dimensions and reorientation energy is successfully used to describe the melting points of n- alkanes(with R=0 9999 and SD=1 07) .
关键词
正烷烃
分子转动惯量
沸点
熔点
AM1
结构
n -alkanes, Molecular rotation model in phase transition, Boiling points and melting points, Sem-empirical method of quantum chemistry
