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Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
Pressure effects on the transitions between disordered phases in supercooled liquid silicon
1Instituto de Física Gleb Wataghin, Universidade Estadual de Campinas, UNICAMP, CEP 13083-859, Campinas, SP, Brazil.
The Journal of Chemical Physics
|December 2, 2011
Summary
Pressure suppresses liquid-liquid transitions in silicon. Above 5 GPa, glassy dynamics halt these transitions, altering the glass transition to involve high-density liquid and amorphous silicon.
Area of Science:
- Condensed matter physics
- Materials science
- Computational chemistry
Background:
- Supercooled liquid silicon exhibits complex phase behavior.
- Understanding transitions between disordered phases is crucial for materials science.
Purpose of the Study:
- Investigate pressure effects on liquid silicon's disordered phase transitions.
- Determine the impact of pressure on liquid-liquid and glass transitions.
Main Methods:
- Monte Carlo simulations
- Computation of free energies
- Environment-dependent interatomic potential for silicon (Si)
Main Results:
- At zero pressure, liquid-liquid transition occurs 325K below melting.
- Liquid-liquid transition temperature decreases with increasing pressure.
- Above 5 GPa, liquid-liquid transition is suppressed by glassy dynamics.
Conclusions:
- Pressure shifts the liquid-liquid coexistence curve towards the glass transition region.
- Above 5 GPa, glass transition involves high-density liquid and high-density amorphous phases.
- Glass transition temperature decreases above 5 GPa due to pressure-induced dynamics.
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