Predicting Solid–Liquid Interfacial Free Energy with Realistic Interfacial Density Wave Amplitudes

This study presents a theoretical framework for predicting the solid–liquid interfacial free energy (γ) of FCC systems using the two-mode Ginzburg–Landau (GL) model, refined with atomistic simulation data to generate more accurate density wave amplitude profiles. The analysis focuses on Lennard-Jones (LJ) systems along the p-T two-phase coexistence boundary. Equilibrium molecular dynamics simulations and the analytical minimization methods are employed to obtain the interfacial density wave amplitude profiles, which serve as inputs for the GL model to predict γ and its anisotropy. The predicted γ values strongly agree with previous benchmark computational studies, with a level of accuracy that surpasses prior predictions using either the GL or phase-field crystal models. The results demonstrate that the current two-mode GL model for FCC solid–liquid interfaces (SLIs) is computationally efficient and quantitatively reliable. It could provide valuable insight into the key factors governing the magnitude and anisotropy of γ and offer theoretical guidance for precisely tuning these properties. To further enhance predictive accuracy, refinements to the variational procedure used in the two-mode SLI free energy functionals are suggested, and potential extensions to the GL model are proposed.