Differential solvation free energies across the ice-water interface: Simple solutes and the SPC/E model of water

Abstract

We characterize the ice-water interface with and without the presence of solute particles using the SPC/E model of water in molecular dynamics simulations. In our simulations, we study the stability of the ice Ih solid structure with respect to the liquid phase and investigate the nature of the ice-water interface for different planes of the crystal. We compare these results to previous results using the CF1 model of water. We also calculate the free energy difference of methane-like solute particles across the interface using a thermodynamic integration technique. Finally, we discuss alternative methods of calculating the free energy and their relative merits, and we allude to the extension to charged solute particles.