Profiles of electrostatic potential across the water-vapor, ice-vapor and ice-water interfaces

TL;DR

This study uses molecular dynamics simulations to analyze electrostatic potential profiles across water-vapor, ice-vapor, and ice-water interfaces, proposing a new calculation method and discussing implications for ion movement.

Contribution

A novel methodology for calculating electrostatic potential profiles across interfaces, validated against existing models and applied to ice-water and vapor interfaces.

Findings

Electrostatic potential decreases towards the liquid bulk in ice-water interface.

Method shows good agreement with previous models.

Results relate to ion movement and the Workman-Reynolds effect.

Abstract

Ice-water, water-vapor interfaces and ice surface are studied by molecular dynamics simulations with the SPC/E model of water molecules having the purpose to estimate the profiles of electrostatic potential across the interfaces. We have proposed a methodology for calculating the profiles of electrostatic potential based on a trial particle, which showed good agreement for the case of electrostatic potential profile of the water-vapor interface of TIP4P model calculated in another way. The measured profile of electrostatic potential for the pure ice-water interface decreases towards the liquid bulk region, which is in agreement with simulations of preferential direction of motion of Li$^{+}$ and F$^{-}$ solute ions at the liquid side of the ice-water interface. These results are discussed in connection with the Workman-Reynolds effect.