Homogeneous crystallization in four-dimensional Lennard-Jones liquids

Abstract

We report the first observation of homogeneous crystallization in simulated high-dimensional ($d > 3$) liquids that follow physically realistic dynamics and have system sizes that are large enough to eliminate the possibility that crystallization was induced by the periodic boundary conditions. Supercooled four-dimensional (4D) Lennard-Jones liquids maintained at zero pressure and constant temperatures $0.59 < T < 0.63$ crystallized within $\sim 2 \times 10^4τ$, where $τ$ is the LJ time unit. WCA liquids that were maintained at the same densities and temperatures at which their LJ counterparts nucleated did not crystallize even after $2.5\times 10^5τ$, showing that the presence of long-ranged attractive interactions dramatically speeds up 4D crystallization, much as it does in 3D. However, the overlap of the liquid and crystalline phases' local-bond-order distributions is much smaller for LJ than for WCA systems, which is the opposite of the 3D trend. This implies that the widely accepted hypothesis that increasing geometrical frustration rapidly suppresses crystallization as the spatial dimension $d$ increases is only generally valid in the absence of attractive interparticle forces.