Layering and phase transition of liquid aluminum confined by different substrates

Molecular dynamics simulation has been performed to study the layering in the nano-confined liquid aluminum, a magic phenomenon characterized by oscillatory density profile across the molecular thin films. Carbon and copper walls are served as the confinement substrates, which can bring about discrepancy in the layering behavior, coordination number and diffusion coefficient. We highlight the abnormal changes of potential energy and volume when the new layer forms, accompanying the distinctive changes of the average coordination number and diffusion coefficient, which is a typical character of phase transition. The role of pressure and temperature on the layering is also reported. Specifically, the pressure-confinement and temperature-confinement diagrams are plotted to further analyze the layering transition. (C) 2017 Elsevier B.V. All rights reserved.