深冷水的热力学反应和相关函数的最大值
Kyung Hwan Kim1, Alexander Späh1, Harshad Pathak1
1Department of Physics, AlbaNova University Center, Stockholm University, SE-10691 Stockholm, Sweden.
概括
研究人员使用X射线激光脉冲研究超冷水滴. 发现表明Widom线存在于深冷水中, 受核量子效应的影响.
科学领域:
- 物理化学
- 热力学
- 软物质物理学
背景情况:
- 在超冷状态下,水表现出复杂的行为,异常表明液体-液体临界点.
- 了解超冷水的热力学对于各种科学领域至关重要.
研究的目的:
- 通过实验探测超冷水和重水的热力学反应和相关函数.
- 在深度超冷水中确定Widom线的存在和特征.
主要方法:
- 在真空中冷却到227K的微米大小的水滴.
- 分析了低动量转移区域的X射线散射数据,以提取同热压缩性和相关长度.
主要成果:
- 在水的229 K和重水的233 K温度下观察到热力学反应和相关函数的最大值.
- 在这些温度下检测到四面体结构的最快增长.
- 同热压缩性的同位素差异突显了核量子效应的意义.
结论:
- 实验结果提供了Widom线存在的证据.
- 这些发现有助于理解水的异常性质以及量子效应在其相位行为中的作用.
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