From Atoms to Clusters and Proteins

芝加哥大学的R. Stephen Berry在理论和计算化学项目的支持下开展了将计算和分析理论相结合的研究，以解决在微观水平上理解日益复杂的系统的动力学问题。研究分为以下几个方面：(1)原子中电子的相关性，(2)小簇和非刚性分子的结构和动力学，(3)混沌或规则动力学与此类系统的动力学之间的关系，(4)小系统的相和相变化，以及这些与体系统中不同顺序的相变之间的关系，(5)多维势面的拓扑结构以及这些拓扑结构如何决定物质的玻璃形成或寻结构特性，(6)将上述主题的概念和结果应用于蛋白质的动力学、折叠和弛豫。该项目的总体目标是增强对由数万到数十万个原子组成的系统的理解和应用。本研究的目标包括开发团簇、纳米级粒子和蛋白质或蛋白质集合如何经历变化的图片，例如熔化和结构变化，磁性到非磁性的转变，或与非常可控的退火相关的重组，可以优化所需形态的产量。团簇是一种特殊形式的物质，它位于孤立的原子和分子之间，一端是固体物质，另一端是固体物质。团簇的性质很重要，因为它们跨越了这两个限制，并且可以使我们理解物质为什么以及如何组织成高度选择性的结构，如晶体材料或正确折叠的蛋白质。这项研究的结果有望加深对物质普通特性的理解，并影响材料科学和生物学等学科的应用。

R. Stephen Berry of the University of Chicago is supported by the Theoretical and Computational Chemistry Program to carry out research that combines computation and analytic theory to address understanding the dynamics of increasingly complex systems at the microscopic level. The research falls into the following areas: (1) correlation of electrons in atoms, (2) structures and dynamics of small clusters and nonrigid molecules, (3) the relation between chaotic or regular dynamics and the kinetics of such systems, (4) the phase and phase changes of small systems, and how these are related to the phase transitions of different orders in bulk systems, (5) the topographies of many-dimensional potential surfaces and how these topographies determine the glass-forming or structure-seeking character of the substance, and (6) the application of the concepts and results of the preceding topics to the dynamics, folding, and relaxation of proteins. The overall objective of this project is to enhance the understanding of and application to systems comprised of tens to hundreds of thousands of atoms. The goals of this study include developing a picture of how clusters, nanoscale particles, and proteins or collections of proteins undergo changes, such as melting and structural changes, magnetic-to-nonmagnetic transitions, or reorganization associated with very controlled annealing that can optimize the yield of a desired morphology. Clusters are special forms of matter that lie between isolated atoms and molecules at one extreme and solid materials at the other extreme. Properties of clusters are important because they bridge these two limits, and can enable understanding of why and how substances organize into highly selective structures such as crystalline materials or properly-folded proteins. The outcomes of this research are anticipated to deepen the understanding of commonplace properties of matter, and impact applications in disciplines such as materials science and biology.