Related Experiment Video
Updated: May 29, 2026
07:32
Monitoring Pedogenic Inorganic Carbon Accumulation Due to Weathering of Amended Silicate Minerals in Agricultural Soils.
Published on: June 4, 2021
Water adsorption on a model silicate surface: wollastonite (100)
Luca Lezuo1, Andrea Conti1, Alexander Hoheneder1
1Institute of Applied Physics, TU Wien, 1040, Vienna, Austria. franceschi@iap.tuwien.ac.at.
Nanoscale
|May 28, 2026
Summary
Water adsorption on calcium silicate surfaces forms distinct structures based on coverage. At low densities, water follows the surface lattice, but higher coverages lead to complex patterns and cluster formation.
Area of Science:
- Surface Science
- Materials Chemistry
- Physical Chemistry
Background:
- Water adsorption on silicate surfaces is crucial for mineral weathering and cement hydration.
- Understanding these interactions at an atomic level is essential for predicting material behavior.
Purpose of the Study:
- To investigate the atomic-scale structure of water overlayers on a model calcium silicate surface (wollastonite).
- To elucidate the interplay between water-surface and water-water interactions at varying coverages.
Main Methods:
- Atomically resolved non-contact atomic force microscopy (nc-AFM) in ultrahigh vacuum.
- Density functional theory (DFT) calculations using the r2SCAN + rVV10 functional.
Main Results:
- At low water coverage (2 molecules/unit cell), water adsorbates follow the wollastonite (100) surface lattice.
- Increased coverage leads to competition between hydrogen bonding and surface interactions, forming complex patterns.
- Above 4 molecules/unit cell, water-water interactions dominate, resulting in cluster formation.
Conclusions:
- The study provides an atomic-scale framework for water interactions with calcium silicate surfaces.
- Experimental symmetries aid in constraining theoretical structural models.
- The findings are relevant to geological processes and material science applications.
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