Primitive model electrolytes. I. Grand canonical Monte Carlo computations

Abstract

Monte Carlo calculations in the grand canonical ensemble are described for coulombic systems, and carried out for 1:1, 2:2, 2:1, and 3:1 aqueous electrolytes in the primitive model with equal ion sizes. Energies and activity coefficients are obtained, and the scope and reliability of the method is discussed.

Individual activity coefficients of a solvent primitive model electrolyte calculated from the inverse grand-canonical Monte Carlo simulation and MSA theory

“…Description of the thermodynamic properties, in particular the ionic activity coefficients, by the mean spherical approximation (MSA) [2,3], symmetric (SPB) [4] and modified (MPB) [5,6] Poisson-Boltzmann theories or by the hypernetted chain equations (HNC) [7] is in good agreement with the simulation results [8][9][10][11][12] for the 1:1 restricted primitive model. Now, the problem lies in the appropriate choice of the model of an electrolyte which will best reproduce the experimental data.…”

“…In SPM solvent molecules are modelled by hard spheres. The mean activity coefficient of ions, γ ± , and the activity coefficient of solvent molecules, γ s , were calculated from the inverse grand-canonical Monte Carlo (IGCMC) simulation [12], and from the MSA at high electrolyte concentrations is observed [8,9], but is similar to that obtained from the experiment. This similarity allows a supposition that by a proper choice of a solvent diameter one will be able to describe the experimental results by simulation techniques or in terms of a theory.…”

Model of cation adsorption on allophanic andisols I. Theory and algorithm

“…The present model is a simple extension of surface complexation models (SCMs), e.g., triple-layer model, by using a simple model of electrolyte solution introduced by Valeau and Cohen (1980). Both surface complex formation and diffuse ion swarm are considered for the adsorption mechanism.…”

Strongly correlated electrostatics of viral genome packaging

“…To properly simulate the DNA bundle at this low c Z limit, we need to include both salts in our simulations. the standard GCMC method [37] is generalized to simulate of a system containing a mixture of both multivalent and monovalent salts. To mimic mixtures used in experiments, we maintain c 1 at about 50 mM and varies c Z from 10 mM to about 300 mM.…”