Applications of convergent beam electron diffraction in materials science

Area of Science:

• Materials Science
• Crystallography
• Electron Microscopy

Background:

• Convergent Beam Electron Diffraction (CBED) is a powerful technique in materials science.
• Standard applications like point-group determination have potential difficulties not always detailed in literature.

Purpose of the Study:

• To review practical applications of CBED in materials science.
• To emphasize areas with known difficulties but limited literature treatment.
• To provide a guide for identifying symmetry-breaking sources in CBED analyses.

Main Methods:

• Review of existing literature and experimental methods for CBED.
• Comparison of different approaches for point-group and space-group determination.
• Analysis of artifacts and symmetry-breaking sources in CBED.

Main Results:

• Detailed comparison of experimental methods for point-group determination using CBED.
• Identification of potential artifacts and sources of symmetry-breaking (crystal structure, defects, strain, morphology).
• Discussion of anomalies in space-group determination and challenges in strain/lattice parameter determination, especially with thin film relaxation.

Conclusions:

• CBED is a versatile tool for materials science, offering insights into crystal structure, defects, and composition.
• Careful consideration of artifacts and experimental conditions is crucial for accurate symmetry determination.
• Further research is needed to address interpretive difficulties in advanced CBED applications like thin film analysis.