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.
