Energetics and Excitations of Glass-Forming Materials

玻璃形成材料的能量和激发

• 批准号: 1265664
• 负责人: David Chandler
• 金额: $ 42万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-09-01 至 2016-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1265664&HistoricalAwards=false
• 关键词: Energetics; Excitations; Glass; Forming; Materials

David Chandler of the University of California, Berkeley is supported by an award from the Chemical Theory, Models and Computational Methods Program in the Chemistry division to carry out research in the area of non-equilibrium statistical mechanics, specifically to elucidate the underlying driving forces and implications of glass transitions. These are transitions of complex systems driven far from equilibrium, transitions manifested in the structure trajectory space. Theoretical techniques have only recently allowed for their systematic analysis, and results from these techniques are now being used in this research to further explore the molecular origins of glass transitions in systems ranging from simple to complex mixtures. In particular, this research aims at predictive theory for the energies and structures of elementary excitations in glass. It should answer how these properties relate to the preparation of the glass, to responses of glass to stress, and to changes in components. The theory should have a degree of generality to reveal implications for other classes of materials, making predictions that can be tested by experiment, and with practical approximations and insights guided by unambiguous results derived from molecular simulation.The work is at the frontier of contemporary statistical physics. Scientists have long understood the principles of equilibrium theory and exploited these principles to design useful ordered and regular condensed phases. Examples include regular solution theory as it is used in the oil-refining industry, and the Ostwald step rule for nucleation used in the steel industry. But no similarly fundamental understanding is yet available for kinetically trapped disordered solids and nanoclusters -- materials, like glass, that emerge by driving liquid matter out of equilibrium. This research is devoted to ameliorating this gap in knowledge. Concerning glasses, in particular, these materials are welcoming and long-term stable hosts for impurities. Glasses are thus materials of choice when contemplating the safe stable storage of radioactive waste materials. Of similar or possibly greater importance, secondary organic aerosols (SOAs) are most often in glassy states. Their transformations play a dominant role in the chemistry of the atmosphere, affecting Earth's climate and human health. This research, therefore, addresses issues pertaining to significant problems in society. Its profound importance together with its fundamental nature makes it superbly appropriate for motivating and training students to become scientists.

加利福尼亚大学伯克利分校的戴维·钱德勒（David Chandler）得到了化学理论，模型和计算方法计划的奖项，以在非平衡统计力学领域进行研究，专门阐明了玻璃过渡的潜在驱动力和意义。 这些是远离平衡的复杂系统的过渡，在结构轨迹空间中表现出来。理论技术直到最近才允许进行系统分析，并且这些技术的结果现在在这项研究中用于进一步探索从简单到复杂混合物的系统中玻璃转变的分子起源。特别是，该研究的目的是针对玻璃中基本激发的能量和结构进行预测理论。它应该回答这些特性与玻璃制备，玻璃对压力的反应以及组件变化的关系。该理论应该具有一定程度的一般性来揭示对其他材料类别的影响，做出可以通过实验测试的预测，并以实用的近似值和见解为指导，这些结果是由分子模拟得出的明确结果引导的。这项工作在当代统计物理学的前沿。 长期以来，科学家已经理解了平衡理论的原理，并利用了这些原理来设计有用的有序和常规凝结阶段。例子包括常规解决方案理论，因为它用于石油额化行业，以及钢铁工业中使用的Ostwald Spep规则。但是，对于动力捕获的无序固体和纳米簇（如玻璃），尚无类似的基本理解，这些材料（例如玻璃）通过将液体物质从平衡中驱逐出来而出现。这项研究致力于改善知识的差距。特别是关于眼镜，这些材料是杂质的热情和长期稳定的宿主。因此，当考虑放射性废料的安全稳定存储时，眼镜是首选的材料。相似或可能更重要的是，次级有机气溶胶（SOA）最常见于玻璃状状态。 它们的转变在大气的化学中起主要作用，影响了地球的气候和人类健康。因此，这项研究解决了与社会重大问题有关的问题。 它的重要性以及其基本性质使其非常适合激励和培训学生成为科学家。