Local structure of liquid gallium under pressure
Renfeng Li1,2, Luhong Wang3, Liangliang Li1,2,4
1Harbin Institute of Technology, Harbin, 150080, China.
Scientific Reports
|July 20, 2017
Summary
High-pressure studies reveal liquid gallium
Area of Science:
- Materials Science
- Condensed Matter Physics
- High-Pressure Research
Background:
- Previous studies suggested liquid gallium's local structure under pressure is a mixture of Ga I and Ga II phases.
- This interpretation was based on fitting experimental pair distribution function (PDF) data to known crystal structures.
- A controversy existed regarding the precise local atomic arrangement in pressurized liquid gallium.
Purpose of the Study:
- To accurately characterize the local structure of liquid gallium under high pressure.
- To resolve the controversy surrounding the structural phases present in pressurized liquid gallium.
- To propose a melting mechanism for gallium based on structural observations.
Main Methods:
- In situ high-energy X-ray pair distribution function (PDF) measurements.
- Microtomography for structural imaging.
- Reverse Monte Carlo (RMC) simulations for data analysis and structural modeling.
Main Results:
- The local structure of liquid gallium up to 1.9 GPa was found to resemble both gallium phase II and phase III.
- This finding contradicts previous suggestions of a mixture solely of Ga I and Ga II.
- The study provides new insights into the atomic arrangement of liquid gallium under pressure.
Conclusions:
- A novel melting mechanism for gallium is proposed.
- This mechanism involves the breakup of the gallium phase I structure upon melting.
- Sufficient free volume is generated for atoms to rearrange into the liquid melt structure.
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