用积分方程方法决定胶粒之间的空耗势

摘要

Binary components Ornstein-Zernike integral equation with the concentration of large particle component being set to zero was employed to study the depletion potential behavior between two large neutral colloid particles (modeled as hard spheres) immersed in a sea of small neutral solvent particles. The prediction for the depletion potential behavior compared well with simulation data and experimental data available in the literature. It is found that the Hansen-Verlet one phase criterion, based on the effective one component system with the present depletion potential, for the freezing transition is completely not suitable for the real binary components system. It is disclosed that the unsuitability is due to the volume term of the solid phase and liquid phase which can not be treated self-consistently in the Hansen-Verlet one phase criterion.%用硬球模中性胶体粒子,数值求解双组分Ornstein-Zernike积分方程(当大的中性胶体粒子的浓度为零时),用来决定悬浮在溶剂(用小的硬球模拟)中两个胶粒之间的空耗势.所预言的空耗势与文献的模拟数据和实验数据能很好地符合.研究发现,基于空耗势的有效一组分Hansen-Verlet 一相相变标准完全不能预言双组分系统的液-固相变.讨论了导致这种现象的原因: Hansen-Verlet 一相相变标准不能自冾地处理有效一组分系统中固相与液相的体积能.