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重新考虑水中液体-液体过渡的证据:解压实验揭示了什么
Rajat Kumar1, Ingrid de Almeida Ribeiro1, Debdas Dhabal2
1Department of Chemistry, The University of Utah, Salt Lake City, Utah 84112-0850, USA.
The Journal of chemical physics
|January 13, 2026
概括
由于纳米领域,水中的液体-液体过渡显示了结构因子S (q) 的单个峰值. 关键的特征是明显的相关长度 ξ,而不是峰值分裂,解决实验矛盾.
科学领域:
- 物理化学 物理化学
- 凝聚物质物理学 凝聚物质物理学
- 材料科学 材料科学 材料科学
背景情况:
- 在超冷水中存在液体-液体过渡 (LLT) 是一个长期的争论.
- 实验研究表明,在解压过程中,液体与液体的共存是基于结构因子S (((q) 的两个峰值.
- 这种解释与仅在液体-液体临界点 (LLCP) 以上共存的理论预测相冲突.
研究的目的:
- 为了调和实验观测和理论预测在水中的LLT之间的明显矛盾.
- 在超冷水中识别LLT的最终结构特征.
- 为了解释在实验中观察到的双峰S ((q) 的起源.
主要方法:
- 使用ML-BOP (基于机器学习的债券订单潜力) 的解压模拟.
- 分析结构因子S(q) 和在低动量转移 (q) 时的看似相关长度 ξ.
- 模拟结果与实验探头数据的比较.
主要成果:
- 模拟显示,即使在LLT期间,由于纳米高密度液体 (HDL) 和低密度液体 (LDL) 领域,S(q) 也保留了一个单一的峰值.
- 实验中的两峰S ((q) 由一个不断演变的液体峰叠加在一个反应较慢,温度梯度较低的冷的HDL上来解释.
- 在低 q 时,明显相关长度 ξ 的短暂增长和衰减被确定为决定性的 LLT 签名,在 LLCP 附近达到顶峰.
结论:
- 在低 q 时的明显相关长度 ξ 演变,而不是 S(q) 峰值分裂,是 LLT 在水中的关键结构标记.
- 实验特征可以通过特定的压力下降形状和随后的 ξ. 的生长和衰变来解释.
- 该研究解决了LLCP位置和观察到的结构特征之间的矛盾,澄清了LLT在水中的性质.
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