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玻璃式冷秤的Prigogine-Defay比率与液体脆弱性有关
A Loidl1, P Lunkenheimer1, K Samwer2
1University of Augsburg, Experimental Physics V, 86135 Augsburg, Germany.
Physical review. E
|April 18, 2025
概括
在玻璃冷过程中,Prigogine-Defay比率 (R) 与材料脆弱性 (m) 强烈相关. 高脆弱性材料接近R≈1,而低脆弱性材料显示R>20,与隐藏的相位过渡有关.
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
- 物理化学 物理化学
背景情况:
- 玻璃材料具有独特的特性,与晶体固体不同.
- 了解玻璃过渡的性质是一个长期以来的科学挑战.
- 普里戈金-德法比 (Prigogine-Defay ratio) (R) 是一种用于分析相位转换的理论参数.
研究的目的:
- 在玻璃系统中研究Prigogine-Defay比率 (R) 和材料脆弱性 (m) 之间的关系.
- 探索这种关系对理解玻璃过渡的含义.
- 为了将R与玻璃过渡到假设的理想玻璃状态的距离相关联.
主要方法:
- 对热容量,热膨胀和压缩性发表的实验数据的分析.
- 对各种材料的Prigogine-Defay比率 (R) 的计算.
- R与材料的脆性指数 (m) 的相关性.
主要成果:
- 在各种材料中观察到R与m的显著依赖.
- 对于高脆弱性 (高m) 材料,R接近~1,与二阶相变相一致.
- 对于低脆弱性 (低m) 材料,R值超过20个.
结论:
- 观察到的R和m之间的相关性为玻璃过渡的性质提供了洞察力.
- 在低脆弱性材料中,R与1的偏差表明了与理想的低温玻璃状态的分离.
- 这项研究将宏观性质 (R,m) 与玻璃结的基础微观行为联系起来.
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