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Updated: May 24, 2026
10:28
Probing the Structure and Dynamics of Interfacial Water with Scanning Tunneling Microscopy and Spectroscopy
Published on: May 27, 2018
Oxide/water interfaces: how the surface chemistry modifies interfacial water properties.
Marie-Pierre Gaigeot1, Michiel Sprik, Marialore Sulpizi
1LAMBE UMR8587, Université d'Evry val d'Essonne, Boulevard F Mitterrand, Bâtiment Maupertuis, F-91025 Evry, France. mgaigeot@univ-evry.fr
Summary
Water organization at silica and alumina oxide interfaces was studied using simulations. Different hydrogen bond strengths explain observed
Area of Science:
- Materials Science
- Physical Chemistry
- Computational Chemistry
Background:
- Understanding water's behavior at oxide interfaces is crucial for various applications, including catalysis and geochemistry.
- The complex interactions at these interfaces influence surface properties and reactivity.
Purpose of the Study:
- To analyze water organization at silica and alumina oxide interfaces.
- To investigate the role of interfacial hydrogen bonding in determining water structure and vibrational spectra.
Main Methods:
- Density functional theory-based molecular dynamics simulations (DFT-MD) were employed.
- Surface charge density and acidity were computed to characterize oxide surfaces.
- Interfacial hydrogen bonding and water molecule orientations were analyzed.
Main Results:
- Water molecule orientation at the interface depends on hydrogen bond strength with the oxide surface.
- Distinct 'ice-like' and 'liquid-like' features in vibrational spectra were observed.
- These spectral features were attributed to varying hydrogen bond strengths between surface silanols/aluminols and water.
Conclusions:
- The study provides a molecular-level understanding of water organization at silica and alumina interfaces.
- DFT-MD simulations successfully explain experimental vibrational spectra by linking hydrogen bond characteristics to spectral features.
- This work enhances the interpretation of sum frequency generation spectroscopy data for oxide-water systems.
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