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Updated: Jul 15, 2026
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Controlling the Size, Shape and Stability of Supramolecular Polymers in Water
Published on: August 2, 2012
The structure of the first coordination shell in liquid water
Ph Wernet1, D Nordlund, U Bergmann
1Stanford Synchrotron Radiation Laboratory, Post Office Box 20450, Stanford, CA 94309, USA.
Science (New York, N.Y.)
|April 3, 2004
Summary
Liquid water molecules primarily exist in two hydrogen-bonded configurations, not the tetrahedral structure of ice. Heating liquid water causes a small shift towards these two-bond structures.
Area of Science:
- Physical Chemistry
- Materials Science
- Condensed Matter Physics
Background:
- Understanding the local molecular structure of liquid water is crucial for many scientific disciplines.
- Previous studies often relied on indirect methods or simulations with varying results.
Purpose of the Study:
- To investigate the local molecular arrangement in the first coordination shell of liquid water.
- To compare the structure of liquid water with hexagonal ice (Ih) and simulated models.
Main Methods:
- Utilized X-ray absorption spectroscopy (XAS) and X-ray Raman scattering (XRS).
- Compared experimental data with bulk and surface hexagonal ice (Ih) and theoretical calculations.
Main Results:
- Liquid water molecules predominantly adopt two hydrogen-bonded configurations, differing from ice's tetrahedral structure.
- A minor fraction (5-10%) of molecules shift from tetrahedral to two-bonded configurations upon heating from 25°C to 90°C.
- Observed significant discrepancies with structures predicted by current molecular dynamics simulations.
Conclusions:
- The local structure of liquid water is characterized by specific hydrogen-bonding arrangements.
- Experimental findings provide stringent constraints for models of liquid water structure.
- Current molecular dynamics simulations may require refinement to accurately represent liquid water's local structure.
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