A general method for calculating solid/liquid interfacial free energies from atomistic simulations: Application to...

Area of Science:

• Computational materials science
• Physical chemistry

Background:

• Calculating solid/liquid interfacial free energies is crucial for understanding material behavior.
• Existing methods face limitations with complex interfaces.

Purpose of the Study:

• To present a general and flexible computational method for determining interfacial free energies.
• To apply this method to specific solid/water interfaces and validate its accuracy.

Main Methods:

• Utilized an Einstein crystal as a universal reference state in atomistic simulations.
• Developed a framework adaptable to surfaces with dipoles, reconstructions, and miscible species.

Main Results:

• Calculated interfacial free energies for bassanite/water and gypsum/water interfaces (~0.12 J/m²), with significant entropic contributions (~45%).
• Determined the interfacial free energy for NaCl/water (~0.13 J/m²), with smaller entropic contributions (~19%).
• Predicted equilibrium morphologies for bassanite and gypsum, showing good agreement with experimental data.

Conclusions:

• The presented method offers a versatile approach for computing interfacial free energies.
• The findings provide valuable insights into the energetics and stability of mineral-water interfaces.