Sodium Chloride, NaCl/ϵ: New Force Field
Raúl Fuentes-Azcatl1, Marcia C Barbosa1
1Instituto de Física, Universidade Federal do Rio Grande do Sul , Caixa Postal 15051, CEP 91501-970 Porto Alegre, Rio Grande do Sul, Brazil.
Abstract:
A new computational model for sodium chloride, the NaCl/ϵ, is proposed. The force field employed for the description of the NaCl is based on a set of radial particle-particle pair potentials involving Lennard-Jones (LJ) and Coulombic forces. The parametrization is obtained by fitting the density of the crystal and the density and the dielectric constant of the mixture of the salt with water at a diluted solution. Our model shows good agreement with the experimental values for the density and for the surface tension of the pure system, and for the density, the viscosity, the diffusion, and the dielectric constant for the mixture with water at various molal concentrations. The NaCl/ϵ together with the water TIP4P/ϵ models provide a good approximation for studying electrolyte solutions.
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