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

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.