From Atoms to Clusters and Proteins

芝加哥大学的R.Stephen Berry得到理论和计算化学项目的支持，开展将计算和分析理论相结合的研究，以解决在微观层面上理解日益复杂的系统的动力学问题。这方面的研究包括：(1)原子中电子的关联，(2)小团簇和非刚性分子的结构和动力学，(3)混沌或规则动力学与这类系统的动力学之间的关系，(4)小系统的相变和相变，以及它们与大块系统中不同级次的相变的关系，(5)多维势表面的形貌以及这些形貌如何决定物质的玻璃形成或结构寻找特性，以及(6)将前面主题的概念和结果应用于动力学、折叠、和蛋白质的松弛。该项目的总体目标是加强对由数万至数十万个原子组成的系统的理解和应用。这项研究的目标包括绘制一张关于簇、纳米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、磁到非磁的转变，或与非常受控的退火相关的重组，以优化所需的形态的产量。团簇是一种特殊形式的物质，位于孤立的原子和分子之间，位于另一端的固体物质之间。团簇的性质很重要，因为它们弥合了这两个限制，并可以使人们了解为什么以及如何将物质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常见性质的理解，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.