Use of the Ornstein-Zernike Percus-Yevick equation to extract interaction potentials from pair correlation functions

作     者：Qifei Wang David J. Keffer Donald M. Nicholson J. Brock Thomas 

作者机构：Department of Chemical and Biomolecular Engineering University of Tennessee Knoxville Tennessee 37996 USA Computer Science and Mathematics Division Oak Ridge National Laboratory Oak Ridge Tennessee 37830-8026 USA Eastman Chemical Company Kingsport Tennessee 37662-5230 USA 

出 版 物：《Physical Review E》 (物理学评论E辑：统计、非线性和软体物理学)

年 卷 期：2010年第81卷第6期

页      面：061204-061204页

核心收录：

学科分类：07[理学] 070203[理学-原子与分子物理] 0702[理学-物理学] 

基　　金：Eastman Chemical Co U.S. Department of Energy, Office of Basic Energy Sciences, Division of Materials Sciences and Engineering NSF [OCI 07-11134.5] 

主　　题：Molecular dynamics 

摘      要：In this work, we test the ability of the Ornstein-Zernike equation in the Percus-Yevick approximation (OZPY) to generate interaction potentials from pair correlation functions (PCFs) of monatomic and diatomic Lennard-Jones fluids. The PCFs are generated by solving OZPY equation (monatomic fluid) and molecular-dynamics (MD) simulations (diatomic fluid). Since the interaction potentials are inputs in the OZPY method and the MD simulation, the extraction of the potential from the PCFs using OZPY is a test of self-consistency. This test is necessary if the procedure is to be used to generate coarse-grained (CG) potentials from PCFs. We find that the procedure is completely self-consistent for the monatomic fluid in the whole range of densities studied (reduced density up to 0.55, under reduced temperature of 2.0). In the diatomic case, we find that the procedure is generally self-consistent under both low and high densities, although there is a systematic deviation at high densities. The method is able to reproduce the two parameters (ε and σ) of the input Lennard-Jones potential model to within about 1%. This CG potential generating procedure can be straightforwardly extended to more complicated molecules.