Solid-Liquid Interfacial Free Energies from Atomistic Mean-Field Quantum Mechanical Calculations

Area of Science:

• Computational materials science
• Physical chemistry
• Quantum mechanics

Background:

• Solid-liquid interfacial free energies (IFEs) are critical for nucleation, wetting, and crystal morphology.
• Accurate, facet-resolved prediction of IFEs remains a significant computational challenge.

Purpose of the Study:

• To develop a novel, fully atomistic mean-field quantum mechanical framework for accurate IFE calculations.
• To enable quantitative, facet-resolved prediction of solid-liquid IFEs.
• To investigate solvent-dependent crystal morphology and stabilization.

Main Methods:

• Integration of a first-principles solid surface with a classical liquid using particle-mesh electrostatics and mean-field approximation.
• A two-stage thermodynamic integration protocol with auxiliary potentials.
• A long-range correction scheme for solid-liquid dispersion interactions.

Main Results:

• Validated methodology against Einstein crystal and dielectric model benchmarks for NaCl-water and PbS-water interfaces.
• Predicted solvent-dependent Wulff morphologies for LiFePO4 facets in water and ethylene glycol.
• Identified enhanced stabilization of the (010) facet due to facet-specific hydroxyl coordination and solvent accessibility.

Conclusions:

• The developed framework enables accurate, facet-resolved IFE predictions.
• The study provides molecular-level insights into solvent effects on crystal facet stabilization and morphology.
• This work advances the computational prediction of interfacial phenomena in materials science.