Transferability of interatomic potentials for silicene

Area of Science:

• Materials Science
• Condensed Matter Physics
• Computational Materials Science

Background:

• Silicene, a 2D allotrope of silicon, exhibits unique electronic and mechanical properties.
• Understanding silicene's behavior requires accurate interatomic potentials for simulations.
• Various silicene polymorphs (e.g., flat, low-buckled) present distinct structural characteristics.

Purpose of the Study:

• To assess the predictive accuracy of commonly used interatomic potentials for silicene.
• To compare the performance of Tersoff, MEAM, Stillinger-Weber, EDIP, ReaxFF, COMB, and machine-learning potentials.
• To identify the most suitable potentials for simulating silicene's structural and mechanical properties.

Main Methods:

• Density Functional Theory (DFT) calculations were employed.
• Molecular Statics (MS) simulations were performed.
• A range of interatomic potentials were systematically tested against DFT results.

Main Results:

• Significant variations in accuracy were observed among the tested interatomic potentials.
• Some potentials accurately reproduced specific structural and mechanical properties of certain silicene polymorphs.
• Machine-learning-based potentials showed promising results for capturing complex silicene behaviors.

Conclusions:

• No single interatomic potential universally excels at predicting all properties of all silicene polymorphs.
• The choice of interatomic potential is critical and depends on the specific silicene phase and properties of interest.
• Further development of interatomic potentials is needed for comprehensive silicene modeling.