U.S.-U.K. Cooperative Research: Computer Simulations of Nonpolar and Polar Flexible Model Compounds

该奖项将支持伊利诺伊大学芝加哥分校的Sohail Murad博士和英国肯特大学坎特伯雷分校的J.G.Powles博士在统计力学方面的持续合作。本项目的目的是全面研究分子柔性对极性和非极性小分子的静态和动态性质的影响。众所周知，为了准确地模拟较大的分子(例如正丁烷)，必须考虑分子的灵活性。然而，最近的一些研究似乎表明，即使是刚性分子的振动柔性也可能是重要的，特别是对于一些动力学性质。调查人员将对这个问题进行审查。拟议的研究将在双原子和三原子分子上进行，并适当放置点电荷来模拟极性分子。这些模型将包括键合拉伸和键合角度弯曲。液体状态将用平衡分子动力学和非平衡分子动力学来研究。这将使研究广泛的性质成为可能。通过将刚性分子的结果与不同柔韧性的结果进行比较，研究人员希望找出对柔韧性最敏感的性质，以便进行更详细的分析。这个拟议的项目代表了两个高素质研究人员之间的合作，这可能会导致更好地了解小分子的热力学和运输性质，特别是那些具有振动自由度的小分子。

This award will support ongoing collaboration in statistical mechanics between Dr. Sohail Murad, University of Illinois at Chicago and Dr. J. G. Powles, University of Kent at Canterbury, England. The objective of this project is to carry out a comprehensive study of the effect of molecular flexibility on the static and dynamic properties of small polar and nonpolar molecules. It is well known that to model accurately, larger molecules (e.g n-butane) one must account for molecular flexibility. However some recent studies appear to indicate that even vibrational flexibility of otherwise rigid molecules may be important, especially for some dynamic properties. The investigators will examine this question. The proposed studies will be carried out on diatomic and triatomic molecules, with point charges placed appropriately to mimic polar molecules. The models will include bond stretching and bond angle bending. The liquid state will be examined using both equilibrium and nonequilibrium molecular dynamics. This will make it possible to investigate a wide range of properties. By comparing results for rigid molecules to those with different degrees of flexibility, the investigators hope to identify properties most sensitive to flexibility for more detailed analysis. This proposed project represents a collaboration between two highly qualified researchers, that is likely to result in a better understanding of the thermodynamic and transport properties of small molecules, especially those with vibrational degrees of freedom.