Dynamics of Equilibrium Liquids, Supercooled Liquids, and Glasses

汉斯·安徒生是由理论和计算科学基金会资助的。 化学计划，继续他的研究动态和平衡 液体，过冷液体和玻璃。 安德森将开发和 使用三种类型的统计力学方法的研究， 稠密过冷流体的动力学理论：1） Martin，Siggia，Rose（MSR）方法应用于 粒子和自旋系统; 2）分子动力学模拟研究 致密、低温和稍微过冷的原子液体;以及3） 动力学自旋模型的时间依赖性的模拟， 阐明了高度松弛和结构变化的机制， 过冷液体和玻璃。 研究的主要目标 是：1）提供的推导和准确性的关键测试， 扩展模式耦合理论和更好地理解物理 理论的内容; 2）发展动力学理论的基础， 使用投影算子或四点 Mazenko的功能;以及3）了解如何将此类 挫折限制域的形成，次要的 弛豫和非均匀弛豫转化为动力学理论。 分子 动力学模拟将用于研究液体， 过冷状态，并且将在较低温度下使用更多示意性的自旋模型 相关时间尺度较长的温度。 玻璃是一种重要的技术材料， 有机和无机成分，均为小分子量 物质和聚合物。 实例包括普通材料，例如 窗户玻璃和食品容器，以及高科技材料， 电信、光电子和固体电解质。 作为 非平衡材料，它们的性质取决于它们是如何制造的， 其通常包括制备高温液体， 通过各种冷却和加工步骤。 制备这种 材料，以实现最佳性能的指导，主要是由经验 观察，但安徒生的研究寻求理解的 这些材料及其相应的液体在一个 分子水平，可用于合理工艺设计 程序.

Hans Andersen is funded by a grant from the Theoretical and Computational Chemistry Program to continue his studies of the dynamics and equilibrium of liquids, supercooled liquids and glasses. Andersen will develop and use three types of statistical mechanical methods for the study of the kinetic theory of dense supercooled fluids: 1) a formulation of the Martin, Siggia, Rose (MSR) approach applied to the classical dynamics of particle and spin systems; 2) molecular dynamics simulation studies of dense, low temperature and slightly supercooled atomic liquids; and 3) simulation of the time dependence of kinetic spin models designed to elucidate mechanisms for relaxation and structural change in highly supercooled liquids and glasses. The major objectives of the research are: 1) to provide critical tests of the derivation and accuracy of the extended mode coupling theory and a greater understanding of the physical content of the theory; 2) to develop a basis for kinetic theory that is an alternative to the use of projection operators or the four-point function of Mazenko; and 3) to understand how to incorporate such phenomena as formation of frustration-limited domains, secondary relaxation, and inhomogeneous relaxation into kinetic theory. Molecular dynamics simulations will be used to study liquids and slightly supercooled regimes, and more schematic spin models will be used at lower temperatures where the relevant time scales are longer. Glasses are technologically important materials made from a variety of components, both organic and inorganic, both small molecular weight substances and polymers. Examples include ordinary materials such as window glass and food containers, as well as high-tech materials for telecommunications, optoelectronics, and solid electrolytes. As nonequilibrium materials, their properties depend on how they are made, which usually involves preparation of a high temperature liquid followed by various cooling and processing steps. The preparation of such materials to achieve optimal performance is guided largely by empirical observations, but Andersen's research seeks an understanding of the dynamics of these materials and their corresponding liquids on a molecular level which can be useful in the design of rational processing procedures.