Site-specific force-vector field studies of KBr(001) by atomic force microscopy

Area of Science:

• Surface Science
• Atomic Force Microscopy
• Computational Materials Science

Background:

• Atomic force microscopy (AFM) is a powerful tool for probing surfaces at the atomic scale.
• Understanding tip-surface interactions is crucial for interpreting AFM data accurately.
• Force field measurements provide detailed information about interatomic forces.

Purpose of the Study:

• To determine the spatial orientation and magnitude of forces between AFM tip atoms and surface atoms.
• To identify the termination of the AFM tip apex.
• To determine the polarity of the KBr(001) surface lattice.

Main Methods:

• Acquisition of force-vector fields along and between ionic lattice sites of a KBr(001) surface.
• Comparison of experimental force fields with atomistic simulations.
• Utilizing two differently configured AFM tips for comprehensive analysis.

Main Results:

• Successful identification of the K(+)-termination at the AFM tip apex.
• Determination of the polarity of the KBr(001) lattice.
• Validation of force field measurements against atomistic simulations.

Conclusions:

• Force field measurements combined with atomistic simulations are effective for characterizing tip-surface interactions.
• This approach enables precise identification of tip apex composition and surface lattice polarity.
• The study provides a detailed understanding of atomic-scale forces on ionic surfaces.