Density-induced molecular arrangements of water inside carbon nanotubes

Water inside carbon nanotubes is an interesting confined system, and its theoretical and applied aspects have been studied extensively. The confinement in nanometer- and sub-nanometer-sized nanotubes gives rise to new molecular arrangements of water and affects its physical properties drastically. In order to study these new arrangements, Monte Carlo simulations of water inside carbon nanotubes have been performed. Simulations are carried out for water with a wide range of density inside carbon nanotubes with different diameters. It is observed that at constant temperature, the density of water dictates the presence of water clusters, filled states, and different ordered phases. The transitions between these states and their effects on the physical properties of this system are studied in detail. The Monte Carlo method is used in the canonical ensemble to simulate water at different densities inside CNTs with different diameters. Different molecular arrangements of water inside the CNTs across a wide range of density are studied. The effects of CNT diameter and water density on the transitions in molecular arrangements are shown.