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Updated: Jul 12, 2026
07:48
An Externally-Heated Diamond Anvil Cell for Synthesis and Single-Crystal Elasticity Determination of Ice-VII at High Pressure-Temperature Conditions
Published on: June 18, 2020
Pressure-Tuned Fermi Resonance in Ice VII
Science (New York, N.Y.)
|June 2, 1995
Summary
Fermi resonance in HDO molecules within D(2)O ice was observed under high pressure. Researchers quantified an anharmonic coupling constant, offering insights into hydrogen bonding in ice.
Area of Science:
- Physics
- Chemistry
- Materials Science
Background:
- High-pressure studies of ice phases are crucial for understanding planetary interiors.
- Hydrogen bonding in water ice exhibits complex behavior under extreme conditions.
Purpose of the Study:
- To investigate Fermi resonance in HDO molecules within D(2)O ice at high pressures.
- To determine the anharmonic coupling constant and its pressure dependence.
Main Methods:
- Spectroscopic analysis of HDO molecules in D(2)O ice.
- Experiments conducted over a pressure range of 17 to 30 gigapascals.
Main Results:
- Fermi resonance was observed between the OH stretch and the overtone of OH bending modes.
- An anharmonic coupling constant was found to be approximately 50 wave numbers.
- The coupling constant exhibited pressure-insensitive behavior.
Conclusions:
- The experimentally determined anharmonic coupling constant provides valuable data for theoretical studies.
- Findings contribute to a deeper understanding of the potential energy surface and hydrogen bonding in ice.
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