Potential of mean force computations of ions approaching a surface

Abstract

We present potentials of mean force (PMF) for sodium and chloride ions approaching inert, hydrophobic, and free surfaces under different pressure conditions. The PMFs were obtained from long (10 ns) molecular dynamics simulations in which special care was taken to include all the relevant long-range electrostatic interactions. We find that chloride ions are slightly more repelled close to the surfaces. The range of the ion repulsion is determined mainly by the width of the water/surface interface, a feature which is not captured by electrostatic images. Show more