非均匀链状分子系统的密度泛函理论

提出了一个基于空穴相关函数的非均匀链状分子系统的密度泛函理论,其中,链分子是相切连接的柔性硬球链,并处于两块平行的无限大平板之间,其亥氏函数理想和剩余两部分组成,它们都是分子密度分布的泛函,其中剩余部分由链的空穴相关函数计算,在数值计算中应用了嵌入计算机分子模拟的方程求解方法,计算了三个链节组成的分子的密度分布,与ＭＣ数据吻合良好。

Functional Theory for Nonuniform Systems Containing Chain-like Molecules

Density functional theory (DFT) for nonuniform systems containing chain like molecules based on cavity correlation functions (CCF) is presented. Chain like molecules confined between two planes are treated as tangent jointed hard sphere chains with intermolecular and intramolecular attractive force between the spheres. The Helmholtz free energy is expressed by two parts:the ideal gas part and the excess part, both are the functionals of the density distribution. The excess part is calculated from the m particle cavity correlation function. The direct iterative algorithm combined with a relaxation factor is used. A single chain Monte Carlo simulation is adopted to compute the density profile of the chain beads. Systems containing trimers are studied. The results satisfactory the coincide with the simulation data.