Electrokinetic properties of NaCl solution via molecular dynamics simulations with scaled-charge electrolytes

In this talk, we are going to explore the ability of scale-charge force fields to describe electrokinetic properties of NaCl aqueous solution in homogeneous and confined media. We validate the force field for bulk thermophysical properties comparing them to experimental data. By combining non-equilibrium and equilibrium molecular dynamics simulations, we obtain the electroosmotic mobility of the solution coupling the shear plane location with the ionic distribution. The zeta potential and the streaming potential coupling coefficient are computed using the Helmholtz-Smoluchowski equation. From an atomic-scale perspective, our molecular dynamics simulations corroborate the hypothesis of maximum packing of the Stern layer, which results in a stable and non-zero zeta potential at high salinity. The scaled-charge model representation of both properties is in excellent qualitative and quantitative agreement with experimental data.