在冲击压缩MGO中的B1-B2过渡
June K Wicks1, Saransh Singh2, Marius Millot2
1Dept. of Earth & Planetary Sciences, Johns Hopkins University, Baltimore, MD 21218, USA.
Science advances
|June 7, 2024
概括
氧化 (MgO) 在极端压力下经历B1到B2晶体结构相位过渡,这对于理解系外行星地幔动态至关重要. 这项研究通过实验确定了高压和高温条件下的MgO相图.
科学领域:
- 行星科学 行星科学
- 地质物理学 地质物理学
- 材料科学 材料科学 材料科学
背景情况:
- 氧化 (MgO) 是行星地幔的关键组成部分.
- 了解MgO的高压行为对于系外行星地幔动态至关重要.
研究的目的:
- 在极端压力下实验确定MgO的相位图.
- 为了研究MgO.中的B1到B2晶体结构相位过渡.
主要方法:
- 激光压缩实验沿着冲击Hugoniot进行.
- 同时测量晶体结构,密度,压力和温度.
- 对相位转换和点的分析.
主要成果:
- 确定了397-425 GPa (~9700 K) 之间的B1到B2相位过渡.
- 观察到一个混合相区域 (B1和B2共存) 从425-493 GPa.
- 发现B2液体共存在500GPa以上,并在634GPa时完全化.
结论:
- 实验数据与理论预测一致,包括声不和性.
- 该研究为极端条件下的MgO相变的时间尺度提供了关键的见解.
- 这项研究弥合了关于MgO的理论和实验研究之间的差距.
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