Nucleation and glassy dynamics in liquids and nanoparticles

液体和纳米颗粒中的成核和玻璃态动力学

• 批准号: RGPIN-2017-05569
• 负责人: SaikaVoivod, Ivan
• 金额: $ 1.53万
• 依托单位: Memorial University of Newfoundland
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2017
• 资助国家: 加拿大
• 起止时间: 2017-01-01 至 2018-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=633592
• 关键词: Nucleation; glassy; dynamics; liquids; nanoparticles

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.

水是一种奇怪的物质，这种液体沐浴着我们的星球，对生命来说是必不可少的。例如，与简单物质相比，它的热膨胀系数、比热和可压缩性都表现出反常的行为，后两者在低温下似乎发散。一种解释水的异常行为的假说听起来更加奇怪：水的两种不同的亚稳态液体形式的存在被一条一级转变线隔开，该线终止于被认为存在于压力在50-200 mpa和温度低于-50°C的液-液临界点(LLCP)。尽管越来越多的实验证据与这一假说一致，并且越来越多的计算机模拟水的模型展示了这种奇异现象，但还没有实验直接显示液-液转变，因为没有一个实验成功地避免了快速结晶，这阻碍了对拟议的LLCP温度和压力范围内的液态的研究。