论文标题
高屏蔽电荷胶体的晶体成核
Crystal Nucleation of Highly-Screened Charged Colloids
论文作者
论文摘要
我们研究了几乎固定的带电胶体颗粒的成核。我们将蒙特卡洛模拟与自由能计算结合使用，以准确预测这些颗粒的相图，并通过冻结密度与硬球绘制它们，然后使用伞采样来探索成核过程。令人惊讶的是，我们发现即使是非常少量的电荷也会对相行为产生重大影响。具体而言，我们发现相位边界和成核屏障主要取决于Debye筛选长度，即使筛选长度的长度小至2％的颗粒直径足以显示两者的明显差异。这项工作清楚地表明，即使是电荷有利的胶体也不是坚硬的球体。
We study the nucleation of nearly-hard charged colloidal particles. We use Monte Carlo simulations in combination with free-energy calculations to accurately predict the phase diagrams of these particles and map them via the freezing density to hard spheres, then we use umbrella sampling to explore the nucleation process. Surprisingly, we find that even very small amounts of charge can have a significant effect on the phase behavior. Specifically, we find that phase boundaries and nucleation barriers are mostly dependent on the Debye screening length, and that even screening lengths as small as 2% of the particle diameter are sufficient to show marked differences in both. This work demonstrates clearly that even mildly charged colloids are not effectively hard spheres.
