Nucleation and glassy dynamics in liquids and nanoparticles

水是地球上的一种液体，是生命所必需的，是一种奇怪的物质。例如，与简单物质相比，其热膨胀系数、比热和可压缩性均表现出异常行为，后两者在低温下出现发散。一种解释水异常行为的假设听起来更奇怪：存在两种不同的亚稳态液体形式的水，它们被一条一阶跃迁线分开，这条跃迁线终止于液-液临界点（LLCP），这种临界点被认为存在于压力在50-200MPa之间，温度低于-50°C。尽管越来越多的实验证据与这一假设相一致，而且越来越多的计算机模拟的类水模型也展示了这种奇特的现象，但没有一个实验直接显示了液-液转变，因为没有一个实验成功地避免了快速结晶，这阻碍了在所提出的LLCP的温度和压力范围内研究液态。

Water, the liquid that bathes our planet and is essential for life, is a strange substance. For example, its thermal expansion coefficient, specific heat and compressibility all show anomalous behavior compared to simple substances, the latter two appearing to diverge at low temperature. A hypothesis that accounts for water's anomalous behaviour sounds stranger still: the existence of two distinct metastable liquid forms of water separated by a line of first order transitions that terminates in a liquid-liquid critical point (LLCP) thought to exist at pressures between 50-200MPa and temperatures below -50°C. Despite an increasing body of experimental evidence consistent with this hypothesis and a growing number of computer simulations of water-like models that exhibit this exotic phenomenon, no experiment has directly shown the liquid-liquid transition, since none has successfully avoided the rapid crystallization that prevents the study of the liquid state in the temperature and pressure range of the proposed LLCP.