Molecular dynamics simulation of liquid water under the influence of an external electric field

Abstract

Molecular dynamics simulations of liquid water were performed at 258K and a density of 1.0 g/cm³ under various applied external electric field, ranging 0∼10¹⁰ V/m. The influence of external field on structural and dynamical properties of water was investigated. The simple point charge (SPC) model is used for water molecules. An enhancement of the water hydrogen bond structure with increasing strength of the electric field has been deduced from the radial distribution functions and the analysis of hydrogen bonds structure. With increasing field strength, water system has a more perfect structure, which is similar to ice structure. However, the electrofreezing phenomenon of liquid water has not been detected since the self-diffusion coefficient was very large. The self-diffusion coefficient decreases remarkably with increasing strength of electric field and the self-diffusion coefficient is anisotropic.

Keywords:

• Molecular simulation
• Molecular dynamics
• Liquid water
• External electric field

Acknowledgements

This study was supported by grants from the National Natural Science Foundation of PR China (No.20276055).