Molecular dynamics simulations of polarizable nanotubes interacting with water

Abstract
In the present paper, we use molecular dynamics simulations to quantify the response of a finite size polarizable nanotube to the electric field created by a water environment. This response is calculated in a self-consistent way at each step of the simulation, leading to the evaluation of the energy and forces coming from the electrostatic interaction between the dipoles induced on the nanotube by the water surrounding and the set of charges accounting for the permanent electric moments of these water molecules. Our results show that the polarization of the nanotube is negligible when it is completely immersed in liquid water at 298K due to the global symmetry of the environment. The polarization effects are slightly more important when considering the case of small water aggregates located outside the nanotube, and they are maximum when the water molecules are located inside the nanotube. However, these polarization effects never account for more than 8% of the total interaction energy and the simulations show that they depend on the geometrical arrangement of the water surrounding.