Homogeneous and heterogeneous nucleation of Lennard-Jones liquids

Abstract

The homogeneous and heterogeneous nucleation of a Lennard-Jones liquid is investigated using the umbrella sampling method. The free energy cost of forming a nucleating droplet is determined as a function of the quench depth, and the saddle point nature of the droplets is verified using an intervention technique. The structure and symmetry of the nucleating droplets is found for a range of temperatures. We find that for deep quenches the nucleating droplets become more anisotropic and diffuse with no well defined core or surface. The environment of the nucleating droplets form randomly stacked hexagonal planes. This behavior is consistent with a spinodal nucleation interpretation. We also find that the free energy barrier for heterogeneous nucleation is a minimum when the lattice spacing of the impurity equals the lattice spacing of the equilibrium crystalline phase. If the lattice spacing of the impurity is different, the crystal grows into the bulk instead of wetting the impurity.

22 pages, 15 figures

References in corpus (1)

• Phase Field Theory of Heterogeneous Crystal Nucleation

Cited by in corpus (7)

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• Glassy aspects of melting dynamics (On melting dynamics and the glass transition, Part I)
• Heterogeneous Nucleation in the Low Barrier Regime
• Suppression of spinodal instability by disorder in an athermal system
• Finite-dimensional signature of spinodal instability in an athermal hysteretic transition
• A critical comparison of general-purpose collective variables for crystal nucleation