受限液体的相变行为  

Confinement effects on phase transitions of water-like liquids

作　　者：孙刚[1] 徐莉梅[1] 

机构地区：[1]北京大学物理学院国际量子材料中心,北京100871

出　　处：《中国科学：物理学、力学、天文学》2016年第5期36-45,共10页Scientia Sinica Physica,Mechanica & Astronomica

基　　金：国家自然科学基金(批准号:11174006;11290162;11525520);国家重点基础研究发展规划(编号:2012CB921404;2015CB856801)资助

摘　　要：水等一类物质有很多不同于其他物质的反常特性.目前存在几种不同理论观点解释水的反常性质,其中最受广泛关注的是水的液体-液体相变理论.实验对这一理论正确与否的验证面临诸多挑战,这是因为理论预测的两种液态之间的相变在极易结晶的深过冷区.目前的液体-液体相变理论实验验证主要集中在受限体系,这是因为体系受限能降低结晶温度使得水在更大温度范围内以液态形式存在进而可以实验探测.但是受限本身引进了额外的自由度,如受限尺度、界面化学性质等,因此受限体系的结果在多大程度上能反映非受限水的性质是一个值得探讨的问题.在这篇综述文章中我们将主要介绍受限对体系液体-液体相变和液体-固体相变的影响.Different from most of other substances, water exhibits many anomalies, such as density anomaly, diffusivity anomaly and thermodynamic anomaly. Different scenarios have been proposed to explain such anomalies, among which the existence of a hypothesized liquid-liquid critical point（LLCP） in deep supercooled water is one of the most discussed.The direct experimental confirmation of LLCP scenario in bulk water is extremely challenging due to unavoidable crystallization in deep supercooled region. Recently, some experimental verification of LLCP is focused on confined water, since confinement suppresses crystallization thus allow for the detection of deep supercooled water. However, by confining water in nano-geometries, additional degrees of freedom are introduced into the system, such as confinement dimension, structural and chemical properties of confining surface. Therefore, to compare the experimental data of confined water with that of bulk water, it is important to consider how confinement affects the phase transition of liquids.Here, we briefly review the recent progress in experiments and simulations on the liquid-liquid phase transition and liquid-solid phase transition in confined liquids.

关 键 词：受限水 液体-液体相变 临界点 亲疏水性 

分 类 号：O414.13[理学—理论物理]