Materials modeling by design: applications to amorphous solids.

Area of Science:

• Materials Science
• Computational Chemistry
• Condensed Matter Physics

Background:

• Modeling amorphous materials is crucial for understanding their properties.
• Existing methods often lack the ability to enforce specific structural or topological constraints.
• Accurate modeling is essential for designing new materials with desired characteristics.

Purpose of the Study:

• To review and present various computational methods for modeling amorphous materials.
• To emphasize techniques that incorporate a priori constraints for improved model accuracy.
• To discuss novel and established approaches for generating realistic amorphous structures.

Main Methods:

• Review of quench from the melt simulations.
• Application of the 'decorate and relax' method for binary glasses.
• Exploration of a 'building block' approach for complex chalcogenides.
• Discussion of explicitly constrained methods like Reverse Monte Carlo (RMC).
• Introduction of 'Experimentally Constrained Molecular Relaxation' (ECMR).

Main Results:

• The 'decorate and relax' method is effective for certain binary glasses.
• A 'building block' approach successfully models GeSe(1.5).
• Insights into vulcanization in Se-As networks and hydrogen incorporation in a-Si.
• ECMR combines ab initio simulation with RMC-like constraints for enhanced accuracy.

Conclusions:

• Constrained modeling approaches significantly improve the reliability of amorphous material simulations.
• The reviewed methods offer versatile tools for generating and refining models of diverse amorphous systems.
• Novel techniques like ECMR represent a promising direction for integrating experimental data into simulations.