Efficient simulation method for nano-patterned charged surfaces in an electrolyte solution

Abstract

We present a method to efficiently simulate nano-patterned charged surfaces inside an electrolyte solution. Simulations are performed in the grand canonical ensemble and are used to calculate the force between surfaces with various charge patterns. The electric field produced by the surfaces is calculated analytically and is used as an external potential. To treat the long range Coulomb interaction between the ions we use a modified 3d Ewald summation method. The force between the surfaces is found to depend strongly on the specific charge pattern, on the surface alignment and separation.

Connecting energetics to dynamics in particle growth by oriented attachment using real-time observations

“…As stated above, full cDFT framework is general enough to include explicit hard-sphere solvent and non-electrostatic mean field solvent-ion interactions that produce a more complete model, which better mimics the experimental system than either the primitive model or previous MD simulations (see Supplementary Discussion for details). However, this complexity renders the cDFT model closer to a full molecular simulation that is difficult to validate-either with more traditional molecular simulations or by performing a self-consistent check of the theory through a full simulation of the charged hard-sphere system in a hard-sphere solvent interacting via a patterned dielectric nanoparticle 59,60 . Moreover, whether a neutral hardsphere is a meaningful representation of an associating fluid (like methanol) is an open question 61 as is the form of the nonelectrostatic solvent interaction.…”

Adsorption of polyelectrolytes on charged microscopically patterned surfaces

“…In the present work, we have studied the adsorption of poly-electrolytes to nano-patterned charged surfaces using a recent method for simulation of these kinds of systems 30 . It is shown that all polyelectrolytes are adsorbed to domains with opposite charge and concentrated at the center of the domains where there is higher charge density.…”

“…Since the system has slab geometry we use a corrected 3D Ewald summation 31 . The total potential energy of the system composed of N hard sphere particles of charge q i located at r r r i can be written as follows 21,30 : where…”

“…One way to produce different patterns is to put point charges on surface 29 , the drawback of this method is that, depending on the surface charge density and surface's size, one should put enough number of particles on the plate which this may lead to slow down the simulation. Recently, an efficient and robust method has been introduced to simulate nanopatterned charged surfaces inside an electrolyte solution 30 . In the mentioned method, to deal with the long-range Coulomb interaction between the ions a modified 3d Ewald summation method was used 31 .…”

Isothermal adsorption of polyampholytes on charged nanopatterned surfaces

“…30 Furthermore, the periodic pattern of the surface becomes imprinted on the electrolyte solution through the renormalization of the Debye length, which controls the interactions between the charged species and The Journal of Chemical Physics ARTICLE scitation.org/journal/jcp the nanopatterned wall. 31,32 Lack of continuous symmetry and presence of strong ionic interactions between charged patches and the monomers of polyampholyte makes the problem very difficult to study using analytical methods. [33][34][35][36] On the other hand, computer simulations provide a direct way to explore both the adsorption and the structure of the polyampholytes near a nanopatterned surface.…”