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Tip-Enhanced Raman Images of Realistic Systems through Ab Initio Modeling
Krystof Brezina1, Yair Litman2,3, Mariana Rossi1,3
1Max Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, 22761 Hamburg, Germany.
ACS Nano
|February 9, 2026
Summary
Simulations of tip-enhanced Raman spectroscopy (TERS) must include substrate effects. Ignoring metallic surfaces alters TERS images, impacting vibrational mode analysis and chemical characterization of surface-bound systems.
Area of Science:
- Surface science
- Spectroscopy
- Computational chemistry
Background:
- Tip-enhanced Raman spectroscopy (TERS) is vital for chemical and vibrational imaging of surfaces.
- Current theoretical simulations often neglect substrate interactions, potentially misrepresenting experimental TERS data.
- Understanding substrate effects is crucial for accurate TERS interpretation.
Purpose of the Study:
- To develop and apply a new simulation method for TERS that includes substrate periodicity.
- To investigate the impact of substrate support on TERS images of 2D materials and molecular systems.
- To elucidate the fundamental principles governing surface interactions in TERS.
Main Methods:
- Developed a finite-field periodic formulation for first-principles simulation of TERS spectra.
- Applied the method to simulate TERS images of defective MoS2 monolayers on metallic substrates.
- Calculated TERS spectra for Mg(II)-porphine on Ag(100) for direct experimental comparison.
Main Results:
- TERS images simulated with cluster models differ significantly from those including substrate periodicity.
- The new method accurately explains experimental TERS intensity variations for Mg(II)-porphine on Ag(100).
- Surface interactions disproportionately affect out-of-plane vibrational modes compared to in-plane modes in TERS.
Conclusions:
- Accounting for substrate periodicity is essential for accurate theoretical TERS simulations.
- The developed simulation approach provides crucial insights into TERS spectroscopy and surface interactions.
- This work offers a valuable tool for interpreting complex TERS data in advanced materials and chemical systems.
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