Simulation of kinematic Kikuchi diffraction patterns from atomistic structures.

Area of Science:

• Materials Science
• Computational Materials Science
• Crystallography

Background:

• Atomistic simulations often lack direct experimental validation due to incompatible output metrics.
• Bridging the gap between simulation data and experimental observations is crucial for materials characterization.
• Existing methods may require prior knowledge of crystal structure or defect periodicity.

Purpose of the Study:

• To develop a method for generating simulated Kikuchi diffraction patterns from atomistic simulation data.
• To enable direct comparison between atomistic simulations and experimental diffraction data without prior structural information.
• To validate the simulation method using models with and without defects.

Main Methods:

• Simulation of Kikuchi diffraction patterns based on kinematic theory of diffraction.
• Computation of Kikuchi line intensities using discrete structure factor calculations.
• Geometric projection of reciprocal space data to map reciprocal lattice points to Kikuchi lines.

Main Results:

• Successful simulation of kinematic Kikuchi diffraction patterns from atomistic models.
• Validation of the method using single crystal atomistic models.
• Demonstration of simulating patterns from models with nanoscale dislocation loops, showing deviations explained by displacement fields.

Conclusions:

• The presented method effectively bridges atomistic simulations and experimental validation through simulated Kikuchi patterns.
• This approach does not require prior specification of crystal structure or defect periodicity.
• The simulation accurately reflects structural details, including the impact of defects like dislocation loops.