Phase transition and superconductivity of selenium under pressure
Enci Zuo1, Yingying Chen2, Gang Jiang1
1Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610065, China. dujg@scu.edu.cn.
Physical Chemistry Chemical Physics : PCCP
|January 27, 2025
Summary
High pressure transforms selenium
Area of Science:
- Condensed matter physics
- Materials science
- Solid-state chemistry
Background:
- Selenium's structural phases under pressure are complex.
- Intermediary phases remain poorly understood.
- High pressure significantly alters selenium's electronic properties.
Purpose of the Study:
- To systematically identify structural and electronic transformations of selenium under high pressure.
- To clarify the atomic arrangement in the monoclinic C2/m phase.
- To investigate the mechanism of superconductivity in high-pressure selenium.
Main Methods:
- First-principles calculations.
- Crystal structure prediction.
- Electron-phonon coupling calculations.
Main Results:
- Identified a transition sequence (P3121 → C2/m → R3̄m → Im3̄m) consistent with experiments.
- Clarified the atomic structure of the C2/m phase.
- Found superconductivity arises from a phase transition, with critical temperature (Tc) increasing with pressure, reaching 13.06 K in the Im3̄m phase.
Conclusions:
- High pressure induces significant structural and electronic changes in selenium.
- Superconductivity in selenium is linked to high-pressure phase transitions.
- Further research is needed to fully understand selenium's high-pressure behavior.
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