Artifactual atomic displacements on surfaces using annular dark-field images with image simulation

Area of Science:

• Materials Science
• Surface Science
• Electron Microscopy

Background:

• Accurate atomic position determination is critical for understanding surface phenomena.
• Scanning transmission electron microscopy (STEM) is a powerful tool for atomic resolution imaging.
• Artifactual displacements in imaging can lead to misinterpretation of surface structures.

Purpose of the Study:

• To investigate artifactual atomic displacements on a platinum (111) surface.
• To evaluate the impact of these artifacts on atomic distance measurements.
• To identify methods for improving the accuracy of atomic position determination on crystal surfaces.

Main Methods:

• Utilized annular dark-field (ADF) scanning transmission electron microscopy (STEM).
• Employed multi-slice image simulation under ideal conditions.
• Applied multiple peak fitting for precise bright spot localization.

Main Results:

• Observed artifactual atomic displacements in Pt (111) surface atomic columns.
• Demonstrated that ADF imaging tends to underestimate surface interatomic distances.
• Showcased multiple peak fitting as an effective technique for accurate atomic positioning.

Conclusions:

• Artifactual displacements affect ADF STEM imaging of crystal surfaces.
• Accurate measurement of interatomic distances on surfaces requires artifact correction.
• Multiple peak fitting offers a robust solution for precise atomic measurements on catalyst surfaces.