Germain Ph, Amokrane S
Physique des Liquides et Milieux Complexes, Faculté des Sciences et Technologie, Université Paris XII, Val de Marne, 61 Avenue du Général de Gaulle, 94010 Créteil Cedex, France.
Phys Rev E Stat Nonlin Soft Matter Phys. 2007 Sep;76(3 Pt 1):031401. doi: 10.1103/PhysRevE.76.031401. Epub 2007 Sep 13.
Motivated by recent experimental results on model binary colloidal mixtures, especially for the glass transition, we investigate the phase diagram of two models of asymmetric binary mixtures: the hard sphere and the Asakura-Oosawa mixtures. This includes the binodals and the glass transition line, computed in the effective one-component representation using the corresponding potentials of mean force at infinite dilution. The reference hypernetted chain approximation is used for computing the static properties and the glass transition line is computed in the mode coupling approximation. The similarities and the differences between the two models are discussed for different size ratios. It is shown that while both models follow a universal behavior at large asymmetry, the hard sphere mixture model leads to more original results at moderate size ratio. These results show that a modeling beyond generic effective potentials might be necessary for an appropriate description of the complete phase diagram.
受近期关于二元胶体混合物模型(特别是玻璃化转变)实验结果的启发,我们研究了两种非对称二元混合物模型的相图:硬球模型和朝仓 - 大泽混合物模型。这包括在有效单组分表示中使用无限稀释时相应的平均力势计算得到的双节线和玻璃化转变线。参考超网链近似用于计算静态性质,玻璃化转变线则在模式耦合近似下计算。针对不同的尺寸比,讨论了这两种模型之间的异同。结果表明,虽然两种模型在大不对称性时都遵循普遍行为,但硬球混合物模型在中等尺寸比时会产生更独特的结果。这些结果表明,对于完整相图的适当描述,可能需要超越一般有效势的建模。