摘要翻译：
研究了弱荷电球形胶体在大小不对称的1：1和2：2盐溶液中的离子吸附。我们利用电解质的原始模型，用超网链/平均球面近似（HNC/MSA）和不等半径修正的Gouy-Chapman积分方程(URMGC)进行了Monte Carlo模拟和理论计算。报道了径向分布函数、积分电荷和平均静电势等结构量。我们的蒙特卡罗“实验”证明，在零电荷点附近，最小的离子物种优先吸附在大粒子上，而不依赖于这个最小的电解组分所携带的电荷的符号，从而导致电荷反转和过充电现象的出现。因此，当宏观离子略微带电，而阴离子大于反离子时，就会观察到电荷反转。在相反的情况下，即如果反离子大于正离子，则发生过充电。换句话说，在本文中，我们提出了第一个关于过电荷的模拟数据，表明这种新的效应在接近零电荷点时浪涌是离子尺寸不对称的结果。此外，在HNC/MSA中包含硬核关联导致了Macroion表面附近的空间区域，其中积分电荷和/或平均静电势随着胶体电荷的增加而减小，反之亦然。这些观察意识到使用标准泊松-玻尔兹曼近似对电泳迁移率测量的解释超出了其有效范围。
---
英文标题：
《Overcharging and charge reversal in the electrical double layer near the
  point of zero charge》
---
作者：
G. I. Guerrero-Garc\'ia (1 and 2), E. Gonz\'alez-Tovar (1), M.
  Ch\'avez-P\'aez (1) and Marcelo Lozada-Cassou (2) ((1) Instituto de F\'isica,
  Universidad Aut\'onoma de San Luis Potos\'i, M\'exico, (2) Programa de
  Ingenier\'ia Molecular, Instituto Mexicano del Petr\'oleo, M\'exico)
---
最新提交年份：
2008
---
分类信息：

一级分类：Physics        物理学
二级分类：Soft Condensed Matter        软凝聚态物质
分类描述：Membranes, polymers, liquid crystals, glasses, colloids, granular matter
膜，聚合物，液晶，玻璃，胶体，颗粒物质
--
一级分类：Physics        物理学
二级分类：Statistical Mechanics        统计力学
分类描述：Phase transitions, thermodynamics, field theory, non-equilibrium phenomena, renormalization group and scaling, integrable models, turbulence
相变，热力学，场论，非平衡现象，重整化群和标度，可积模型，湍流
--

---
英文摘要：
  The ionic adsorption around a weakly charged spherical colloid, immersed in size-asymmetric 1:1 and 2:2 salts, is studied. We use the primitive model of an electrolyte to perform Monte Carlo simulations as well as theoretical calculations by means of the hypernetted chain/mean spherical approximation (HNC/MSA) and the unequal-radius modified Gouy-Chapman (URMGC) integral equations. Structural quantities such as the radial distribution functions, the integrated charge, and the mean electrostatic potential are reported. Our Monte Carlo "experiments" evidence that near the point of zero charge the smallest ionic species is preferentially adsorbed onto the macroparticle, independently of the sign of the charge carried by this tiniest electrolytic component, giving rise to the appearance of the phenomena of charge reversal and overcharging. Accordingly, charge reversal is observed when the macroion is slightly charged and the coions are larger than the counterions. In the opposite situation, i.e. if the counterions are larger than the coions, overcharging occurs. In other words, in this paper we present the first simulational data on overcharging, showing that this novel effect surges close to the point of zero charge as a consequence of the ionic size asymmetry. Further, it is seen that the inclusion of hard-core correlations in HNC/MSA leads to spatial regions near the macroion's surface in which the integrated charge and/or the mean electrostatic potential can decrease when the colloidal charge is augmented and vice versa. These observations aware about the interpretation of electrophoretic mobility measurements using the standard Poisson-Boltzmann approximation beyond its validity region.
---
PDF链接：
https://arxiv.org/pdf/801.2612