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Updated: Jun 14, 2026
06:26
Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
Structure and phase boundaries of compressed liquid hydrogen
Isaac Tamblyn1, Stanimir A Bonev
1Department of Physics, Dalhousie University, Halifax, NS, B3H 3J5, Canada. itamblyn@dal.ca
Physical Review Letters
|April 7, 2010
Summary
Researchers mapped the molecular-atomic transition in liquid hydrogen. A new molecular phase with orientational order was discovered above 100 GPa, explaining the sharp transition and pressure drop.
Area of Science:
- Condensed matter physics
- High-pressure physics
- Computational materials science
Background:
- Understanding the behavior of hydrogen under extreme conditions is crucial for astrophysics and materials science.
- The molecular-atomic transition in hydrogen is a key phenomenon at high pressures.
Purpose of the Study:
- To map the molecular-atomic transition in liquid hydrogen.
- To investigate the structural ordering and its impact on the transition dynamics.
Main Methods:
- First principles molecular dynamics simulations.
- Ab initio calculations.
Main Results:
- Predicted a molecular phase with short-range orientational order above 100 GPa.
- Explained the sharpness of the molecular-atomic crossover and the pressure drop.
- Identified implications for existing equation of state data for molecular hydrogen.
Conclusions:
- The observed orientational order provides a mechanism for the sharp transition.
- Current models of hydrogen's equation of state may need revision.
- The study supports the possibility of a first-order liquid-liquid transition in hydrogen.
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