Potassium bromide, KBr/{\epsilon} : New Force Field

TL;DR

This paper introduces a new force field model for potassium bromide (KBr/epsilon) to accurately simulate ionic interactions in biomolecular systems, validated against experimental properties and extended to related ions for transferability.

Contribution

The paper develops and validates a novel force field for KBr, demonstrating its transferability and accuracy in reproducing key physical properties compared to experimental data.

Findings

KBr/epsilon accurately reproduces crystal density and structure.

The model predicts solution properties like density, viscosity, dielectric constant, and solubility.

Transferability of the force field to related ions is successfully demonstrated.

Abstract

The correct description of the ionic interaction and stable equilibrium of the simulations of biomolecular structure, dynamics, folding, catalysis, and function, an accurate model of the monovalent ions is very important. The force field needs to reproduce coincident many properties of ions, like their structure, solvation, and moreover both the interactions of these ions with each other in the crystal and in solution and the interactions of ions with other molecules. Using a similar strategy employed in the parameterization of the NaCl/epsilon , in this paper, we first propose a force field for the Potassium Bromide, the KBr/epsilon. This new model is compared with the experimental values of cristal density and structure for the salt and the density, the viscosity, the dielectric constant and the solubility in the water solution for a range of concentrations. Next, the transferability, of this new model KBr/epsilon and the NaCl/epsilon, is verified by creating the KCl/epsilon and the NaBr/epsilon models. The strategy is to employ the same parameters obtained for the NaCl/epsilon and for the KBr/epsilon force fields. The two new models derived are also compared with the experimental values for the density, the viscosity, the dielectric constant and the solubility in the water solution for a range of concentrations.