2D versus 3D Freezing of a Lennard-Jones Fluid in a Slit Pore

TL;DR

This study uses computer simulations to compare how a Lennard-Jones fluid freezes in two-dimensional and three-dimensional slit pore confinements, revealing different phase transition behaviors.

Contribution

It provides a detailed analysis of the freezing transition in confined Lennard-Jones fluids, highlighting the transition from 2D to 3D crystallization as slit width varies.

Findings

Layering occurs near walls during freezing.

Transition from 2D to 3D crystallization with changing slit width.

Identification of hexatic phase in intermediate states.

Abstract

We present a computer simulation study of a (6,12)-Lennard-Jones fluid confined to a slit pore, formed by two uniform planes. These interact via a (3,9)-Lennard-Jones potential with the fluid particles. When the fluid approaches the liquid-to-solid transition we first observe layering parallel to the walls. In order to investigate the nature of the freezing transition, we performed a detailed analysis of the bond-orientational order parameter in the layers. Changing the distance between the slit wall, we studied howthe behaviour changes from a quasi-2d crystallization without hysteresis and an intermediate hexatic phase to a standard 3d nucleation.