University of Rochester Laboratory for Laser Energetics, Rochester, New York 14623-1299, USA.
Department of Mechanical Engineering, University of Rochester, Rochester, New York 14627-0132, USA.
Phys Rev Lett. 2023 Feb 17;130(7):076101. doi: 10.1103/PhysRevLett.130.076101.
Silicon (Si) exhibits a rich collection of phase transitions under ambient-temperature isothermal and shock compression. This report describes in situ diffraction measurements of ramp-compressed Si between 40 and 389 GPa. Angle-dispersive x-ray scattering reveals that Si assumes an hexagonal close-packed (hcp) structure between 40 and 93 GPa and, at higher pressure, a face-centered cubic structure that persists to at least 389 GPa, the highest pressure for which the crystal structure of Si has been investigated. The range of hcp stability extends to higher pressures and temperatures than predicted by theory.
硅（Si）在环境温度等温条件和冲击压缩下表现出丰富的相变。本报告描述了在 40 至 389 GPa 之间的斜坡压缩 Si 的原位衍射测量。角度色散 X 射线散射表明，Si 在 40 至 93 GPa 之间呈六方密排（hcp）结构，在更高的压力下呈面心立方结构，至少在 389 GPa 时保持这种结构，这是 Si 的晶体结构研究的最高压力。hcp 稳定性的范围比理论预测的更高的压力和温度。
