Nucleation, glass formation, and phase behavior in supercooled liquids

过冷液体中的成核、玻璃形成和相行为

• 批准号: 183674-2011
• 负责人: Poole, Peter
• 金额: $ 4.15万
• 依托单位: St. Francis Xavier University
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2015
• 资助国家: 加拿大
• 起止时间: 2015-01-01 至 2016-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=569650
• 关键词: Nucleation; glass; formation; phase; behavior

The liquid state is an enduring source of challenges for our understanding of matter. Even the simplest classical liquid is a dense, disordered, and strongly-interacting many-body system. Liquids thus present us with rich behavior and formidable complexity, especially at the molecular scale. Some of the most important and perplexing open questions in liquid-state physics occur in supercooled liquids. The nature of amorphous solid formation at the glass transition is a continuing source of open debate. Similarly, the nucleation of crystalline solids from the liquid state is also incompletely understood; e.g. the ability of theory to predict crystal nucleation rates with quantitative accuracy remains poor for many important systems. While many of these questions are of a fundamental nature, practical applications abound. For example, the glass-forming ability of metallic alloys is an area of active commercial interest, with new companies making amorphous metal products such as golf clubs and aircraft components. Colloidal liquids are also an area of explosive growth, to which our understanding of classical molecular liquids is directly transferrable. In the context of supercooled liquids, a number of distinct and complex phenomena converge: the thermodynamics of metastable phases; the complex transport properties of viscous liquids; and the non-equilibrium kinetics of crystal nucleation. This proposal describes a program of research to investigate the properties of supercooled liquids, with a deliberate focus on regimes in which these phenomena become intertwined, to better understand all of them. This work will be carried out using molecular dynamics computer simulations, from which both molecular-scale details, as well as estimates of bulk material properties may be obtained.

液态状态是我们对物质理解的持久挑战。 即使是最简单的经典液体也是一种密集，无序且强烈相互交互的多体系统。 因此，液体具有丰富的行为和强大的复杂性，尤其是在分子尺度上。 在超冷液体中，液态物理学中一些最重要，最困惑的开放性问题发生在超冷液体中。玻璃过渡时无定形固体形成的性质是开放辩论的持续来源。 同样，还不完全了解了液态的结晶固体的成核。例如对于许多重要系统，理论以定量准确性预测晶体成核的能力仍然很差。 尽管其中许多问题具有基本的性质，但实际应用比比皆是。例如，金属合金的玻璃形成能力是一个具有积极商业兴趣的领域，新公司生产了高尔夫球俱乐部和飞机组件等无定形金属产品。 胶体液体也是爆炸性生长的区域，我们对经典分子液体的理解是直接转移的。 在超冷液体的背景下，许多不同的复杂现象会融合：亚稳态相的热力学；粘性液体的复杂运输特性；以及晶体成核的非平衡动力学。该提案描述了一项研究计划，以研究超冷液体的特性，并故意关注这些现象交织在一起的制度，以更好地了解所有这些现象。 这项工作将使用分子动力学计算机模拟进行，可以从中获得分子规模的细节，以及可以获得大量材料特性的估计。