Simulations of ionic liquids confined by metal electrodes using periodic Green functions

Abstract

We present an efficient method for simulating Coulomb systems confined by metal electrodes. The approach relies on Green function techniques to obtain the electrostatic potential for an infinite periodically replicated system. This avoids the use of image charges or an explicit calculation of the induced surface charge, both of which dramatically slows down the simulations. To demonstrate the utility of the new method, we use it to obtain the ionic density profiles and the differential capacitances, which are of great practical and theoretical interest, for a lattice model of an ionic liquid.

Simulation of a Solvate Ionic Liquid at a Polarizable Electrode with a Constant Potential

“…47,48 However, this plot of capacitance against potential differs somewhat from that obtained for conventional ionic liquids using green functions to model a universally polarisable metal surface, while both results show a general decrease in capacitance with dilution, the prior prediction does not show the peak away from the zero potential we see here, but such was observed for dilute electrolytes. 49,50 There are a couple of possible reasons for this difference, one is the presence of this peak may be due to the atomistic nature of the electrode, as in previous studies of the capacitance of water at platinum electrodes and ionic liquids at graphitic electrodes. Alternatively this may be due to a specific difficulty in modelling solvate ionic liquids using the methodology of Girotto et al 49,50 In their 2017 paper the liquid is modeled using two parameters: one for ion size and the other the Bjerrum length.…”

“…Alternatively this may be due to a specific difficulty in modelling solvate ionic liquids using the methodology of Girotto et al 49,50 In their 2017 paper the liquid is modeled using two parameters: one for ion size and the other the Bjerrum length. 50 The problem is that the size of a solvate ionic liquid cation changes with chelation and dechelation, which has been shown in this paper to have some degree of surface dependence, this dynamic would also be expected to lead to broad changes in the The results in this study differ significantly from the previous study with fixed charge electrodes. 14 Primarily in the presence of a dechelation dynamic, which is induced by surface polarisability.…”

Effect of proximity to ionic liquid-solvent demixing on electrical double layers

“…Nevertheless, we assume ǫ to be temperature-independent, and note that its temperature variation should not affect the results qualitatively, as pointed out in [30]. In addition, it is known that polarizability of solvent and of ions may play an important role in the structure and properties of electrical double layers [36][37][38][39][40][41]. In particular, Gongadze and Iglič [36] demonstrated a potentially strong variation of the dielectric constant close to a planar charged surface.…”

Like-Charge Attraction between Metal Nanoparticles in a1∶1Electrolyte Solution

“…To overcome a slow convergence of the numerical solution of the full non-linear Poisson-Boltzmann equation, we developed a modified Derjaguin approximation which allows us to accurate and rapidly calculate the interaction potential between two metal nanoparticles, or between a metal nanoparticle and a phospholipid membrane. a) Electronic mail: alexandre.pereira@ufrgs.br b) Electronic mail: levin@if.ufrgs.br Metal nanoparticles suspended in an electrolyte solution have attracted a lot of attention for various applications [1][2][3][4][5][6][7][8][9][10] . Because of their strong affinity for biological surfaces and compatibility with immune system 11 , gold nanoparticles are being used for cancer treatment and drug delivery [12][13][14] .…”