Can atom-surface potential measurements test atomic structure models?

Area of Science:

• Atomic and Molecular Physics
• Surface Science
• Computational Chemistry

Background:

• Van der Waals (vdW) potentials are crucial for understanding atom-surface interactions.
• vdW potentials serve as benchmarks for atomic structure calculations.
• Experimental measurements using different atoms on the same surface offer unique insights.

Purpose of the Study:

• To theoretically investigate the dependence of vdW potential strength ratios on atomic and surface properties.
• To identify optimal atomic pairs for experimental validation of atomic structure calculations.
• To elucidate the role of atomic core and valence electrons in vdW interactions.

Main Methods:

• Theoretical modeling of van der Waals (vdW) atom-surface potentials.
• Utilizing a two-oscillator model to differentiate contributions from atomic valence and core electrons.
• Analyzing the sensitivity of C₃ ratios to atomic and surface parameters, including permittivity.

Main Results:

• Ratios of vdW potential strengths (e.g., C₃(K)/C₃(Na)) are highly sensitive to individual atomic properties.
• These C₃ ratios exhibit relative insensitivity to the properties of the surface material.
• The theoretical model successfully explains the dependence of C₃ ratios on atomic core electrons.

Conclusions:

• The study provides a theoretical framework for understanding vdW potential ratios.
• Selecting appropriate atomic pairs (e.g., K and Na) is key for robust atomic structure calculations.
• Future experiments can leverage these findings for precise atomic structure determination by minimizing surface-dependent variations.