Abstract:

The molecular dynamics diameter of the preferred conformation is calculated by using the Gaussian software molecular mechanics(MM2) force field/density functional theory method. This method can describe the shape and structure of alkane molecules more stereoscopically, intuitively, accurately and comprehensively from the three-dimensional direction. Comparing the results of molecular dynamics diameter calculated by Gaussian software simulation with the results of molecular distillation experiment, it is concluded that the distance between cold and hot surfaces of the equipment is greater than the mean free path of alkane light molecules calculated by Langmuir formula, and the direct simulation Monte Carlo(DSMC) method can more accurately simulate the results of molecular distillation cutting.

Key words: molecular distillation, F-T wax, preferred conformation, mean free path

摘要：

利用高斯软件分子力场(MM2)/密度泛函数对分子优势构象时的分子动力学直径进行了计算，该方法能从三维方向上更加立体、直观、准确、全面地描述烷烃分子的形状结构。将高斯软件模拟计算的分子动力学直径结果与短程蒸馏实验结果对比，得出设备冷热面间距大于Langmuir公式计算的烷烃轻分子平均自由程，蒙特卡罗方法(DSMC)能更准确地模拟分子蒸馏切割结果。

关键词: 短程蒸馏, 费托蜡, 优势构象, 平均自由程