机器学习模拟揭示了氧气的相位图和热性质在与白矮星相关的条件下
Yunlong Wang1, Jiuyang Shi1, Zhixin Liang1
1National Laboratory of Solid State Microstructures, School of Physics and Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing, China.
Nature communications
|July 2, 2025
概括
高压将氧气转化为聚合物相,揭示了新的晶体结构和异常的化行为. 这些发现表明,富含氧气的环境可能会加速白矮星的冷却.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 星球科学 星球科学
- 材料科学是一种材料科学.
背景情况:
- 目前的研究表明,即使在极端压力 (高达10 TPa) 下,氧气也不会聚合.
- 关于高压下密集氧的行为存在一个重要的知识差距.
研究的目的:
- 为了研究在极端压力下氧气的完整聚合过程.
- 为了确定密集氧的晶体结构和热力学特性.
主要方法:
- 使用结构预测方法来确定高达1PPa的氧气晶体结构.
- 机器学习潜力分子动力学和双相方法被用于构建高达200 TPa的化曲线.
主要成果:
- 确定了一种新的二维结合体中心四边形 (bct) 阶段和一个完全聚合的六边形密封 (hcp) 阶段.
- 在超过100 TPa的氧气中观察到异常的化行为.
- 氧的导热率高,同等压力下同位体热容量低于.
结论:
- 氧在高压下经历完全聚合,形成新的晶体相.
- 密集氧的确定的特性,包括其化曲线和热特性,对天体物理学有影响.
- 富含氧气的包裹可以加速白矮星的冷却.
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