Transferability of Molecular Potentials for 2D Molybdenum Disulphide

Area of Science:

• Materials Science
• Computational Chemistry
• Condensed Matter Physics

Background:

• Two-dimensional (2D) molybdenum disulphide (MoS2) exhibits diverse polymorphs with unique properties.
• Accurate computational modeling is crucial for understanding and designing MoS2-based materials.
• The reliability of interatomic potentials significantly impacts simulation outcomes.

Purpose of the Study:

• To assess the performance of various molecular potentials in reproducing the structural, mechanical, and vibrational properties of different 2D MoS2 phases.
• To provide a systematic comparison of density functional theory (DFT) and molecular statics (MS) results using selected potentials.
• To identify suitable potentials for future simulations of single-layer MoS2 (SL MoS2).

Main Methods:

• Density functional theory (DFT) calculations were performed.
• Molecular statics (MS) simulations were conducted.
• Stillinger-Weber, REBO, SNAP, and ReaxFF interatomic potentials were employed to model SL MoS2 (1H, 1T, and 1T' phases).

Main Results:

• The study systematically compared the accuracy of DFT and MS methods with different potentials.
• Structural parameters, mechanical moduli, and phonon dispersion relations were analyzed for each MoS2 phase.
• Discrepancies between potential predictions and DFT data were quantified.

Conclusions:

• The performance of molecular potentials varies significantly for different 2D MoS2 polymorphs.
• Certain potentials demonstrate better agreement with DFT for specific properties and phases.
• This comparative analysis aids in selecting appropriate computational tools for MoS2 research.