An efficient computational method for use in structural studies of crystals with substitutional disorder

Area of Science:

• Materials Science
• Computational Chemistry
• Solid-State Physics

Background:

• Determining the average atomic structure of disordered crystals is computationally challenging.
• Standard first-principles methods are accurate but computationally intensive.
• Substitutional disorder in crystals requires specialized approaches for structural analysis.

Purpose of the Study:

• To develop a computationally efficient semi-empirical method for determining the average atomic structure of crystals with substitutional disorder.
• To integrate standard first-principles techniques with the virtual crystal approximation.
• To establish a minimization problem framework using experimental data for structural determination.

Main Methods:

• Utilizing standard first-principles techniques combined with the virtual crystal approximation.
• Defining figures of merit based on minimal experimental information.
• Recasting the average atomic ordering determination as a minimization problem.

Main Results:

• The proposed method accurately determines the average atomic structure of disordered crystals.
• Successfully applied to diverse materials including oxynitrides, borocarbides, and perovskite oxides.
• Reproduced experimental solutions and first-principles results with significantly reduced computational cost.

Conclusions:

• The developed semi-empirical method offers an efficient and accurate alternative for analyzing disordered crystal structures.
• This approach provides a valuable tool for materials discovery and characterization.
• The integration of experimental data and computational modeling enhances structural prediction capabilities.