Varga I, Kun F, Pál K F
Department of Theoretical Physics, University of Debrecen, PO Box 5, H-4010 Debrecen, Hungary.
Phys Rev E Stat Nonlin Soft Matter Phys. 2004 Mar;69(3 Pt 1):030501. doi: 10.1103/PhysRevE.69.030501. Epub 2004 Mar 25.
A theoretical study of the structure formation observed very recently [W. D. Ristenpart, I. A. Aksay, and D. A. Saville, Phys. Rev. Lett. 90, 128303 (2003)] in binary colloids is presented. In our model solely the dipole-dipole interaction of the particles is considered, electrohydrodynamic effects are excluded. Based on molecular dynamics simulations and analytic calculations we show that the total concentration of the particles, the relative concentration, and the relative dipole moment of the components determine the structure of the colloid. At low concentrations the kinetic aggregation of particles results in fractal structures which show a crossover behavior when increasing the concentration. At high concentration various lattice structures are obtained in a good agreement with experiments.
本文给出了对最近[W. D. 里斯滕帕特、I. A. 阿克赛和D. A. 萨维尔，《物理评论快报》90, 128303 (2003)]在二元胶体中观察到的结构形成的理论研究。在我们的模型中，仅考虑了粒子的偶极 - 偶极相互作用，排除了电流体动力学效应。基于分子动力学模拟和解析计算，我们表明粒子的总浓度、相对浓度以及各组分的相对偶极矩决定了胶体的结构。在低浓度下，粒子的动力学聚集导致分形结构，当浓度增加时，这些结构呈现出交叉行为。在高浓度下，获得了各种晶格结构，与实验结果吻合良好。
