Pezeshkian Weria, Nikoofard Narges, Norouzi Davood, Mohammad-Rafiee Farshid, Fazli Hossein
Department of Physics, Institute for Advanced Studies in Basic Sciences (IASBS), Zanjan 45137-66731, Iran.
Phys Rev E Stat Nonlin Soft Matter Phys. 2012 Jun;85(6 Pt 1):061925. doi: 10.1103/PhysRevE.85.061925. Epub 2012 Jun 28.
The distribution of counterions and the electrostatic interaction between two similarly charged dielectric slabs is studied in the strong coupling limit. Dielectric inhomogeneities and discreteness of charge on the slabs have been taken into account. It is found that the amount of dielectric constant difference between the slabs and the environment, and the discreteness of charge on the slabs have opposing effects on the equilibrium distribution of the counterions. At small interslab separations, increasing the amount of dielectric constant difference increases the tendency of the counterions toward the middle of the intersurface space between the slabs and the discreteness of charge pushes them to the surfaces of the slabs. In the limit of point charges, independent of the strength of dielectric inhomogeneity, counterions distribute near the surfaces of the slabs. The interaction between the slabs is attractive at low temperatures and its strength increases with the dielectric constant difference. At room temperature, the slabs may completely attract each other, reach to an equilibrium separation, or have two equilibrium separations with a barrier in between, depending on the system parameters.
在强耦合极限下，研究了抗衡离子的分布以及两个带相似电荷的电介质平板之间的静电相互作用。考虑了平板上的介电不均匀性和电荷离散性。发现平板与环境之间的介电常数差值以及平板上电荷的离散性，对抗衡离子的平衡分布具有相反的影响。在平板间距较小时，增加介电常数差值会增加抗衡离子向平板间界面空间中间移动的趋势，而电荷离散性则将它们推向平板表面。在点电荷极限下，与介电不均匀性强度无关，抗衡离子分布在平板表面附近。在低温下，平板之间的相互作用是吸引性的，其强度随介电常数差值增加。在室温下，根据系统参数，平板可能会完全相互吸引、达到平衡间距，或者存在两个平衡间距且中间有一个势垒。
