黑色的化曲线:证据表明固体-液体-液体三重点
Hermann Muhammad1, Mohamed Mezouar1, Gaston Garbarino1
1European Synchrotron Radiation Facility (ESRF), 71 Avenue des Martyrs, 38043 Grenoble, France.
The journal of physical chemistry letters
|August 8, 2024
概括
研究人员绘制了黑融化曲线的地图,揭示了两个不同的液相和三重点. 这为了解黑合成和压力下的稳定性提供了关键数据.
科学领域:
- 材料科学 材料科学 材料科学
- 凝聚物质物理学 凝聚物质物理学
- 晶体学 晶体学是指结晶学.
背景情况:
- 黑 (bP) 由于其多层结构,具有独特的异构性质.
- 了解压力-温度 (P-T) 阶段图,特别是化曲线,对于bP合成和稳定性至关重要.
- 关于bP化曲线的现有数据存在重大不确定性.
研究的目的:
- 准确确定黑在延长的P-T范围内的化曲线.
- 在bP相位图中识别相位过渡和关键点.
- 为控制BP合成和应用提供基本数据.
主要方法:
- 在现场高压和高温同步X射线衍射.
- 利用bP的异型热弹性特性进行精确的P和T测定.
- 研究的相位行为从0.10(3) 到5.05(40) GPa和914(25) 到1788(70) K.
主要成果:
- 观察到化温度随着压力的单调增加.
- 确定了两种不同的线性化曲线下方和上方的1.35~15) GPa,具有不同的斜率.
- 位于1.35(15) GPa和1350(25) K的三重点,对应于融化成低密度和高密度液体.
- 具有特征的晶化后阶段:高密度液体改革bP,低密度液体形成复杂的晶体/无形固体 (红色和紫色P混合物).
结论:
- 该研究精确地定义了黑的化曲线,并确定了三重点.
- 黑存在两个不同的液态相,具有不同的结晶行为.
- 准确的P-T数据有助于更好地了解黑的基本特性和合成条件.
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