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Updated: May 13, 2026
10:28
Probing the Structure and Dynamics of Interfacial Water with Scanning Tunneling Microscopy and Spectroscopy
Published on: May 27, 2018
Microscopic structure of water at elevated pressures and temperatures
Christoph J Sahle1, Christian Sternemann, Christian Schmidt
1Fakultät Physik/Dortmund Electron Accelerator, Technische Universität Dortmund, Dortmund, Germany. christoph.sahle@helsinki.fi.
Summary
Researchers explored water
Area of Science:
- Physical Chemistry
- Materials Science
- Spectroscopy
Background:
- Understanding water's microscopic structure is crucial for various scientific disciplines.
- Sub- and supercritical conditions significantly alter water's properties.
Purpose of the Study:
- To investigate the microscopic structure of water under sub- and supercritical conditions.
- To correlate spectroscopic data with theoretical simulations.
Main Methods:
- X-ray Raman spectroscopy for experimental analysis.
- Ab initio molecular dynamics simulations for theoretical modeling.
- Density functional theory for electronic structure calculations.
Main Results:
- Observed systematic spectral changes with varying temperature and pressure.
- Validated a structural model from simulations against experimental spectra.
- Demonstrated nanometer-scale homogeneity of the water structure.
- Quantified dramatic increases in hydrogen-bond network distortions in the supercritical regime.
Conclusions:
- The hydrogen-bond network in water significantly distorts under supercritical conditions.
- The average number of hydrogen bonds per molecule drastically decreases at high temperatures and pressures.
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