Dynamics of Nanostructures: Clusters, Polymers, and Surfaces

该项目将探索两个主要主题：1)应用新的衍射技术，以原子尺度的空间分辨率检查固体表面和材料；2)实时研究凝聚相中的溶剂化。这些研究活动的智力价值源于新的实验技术和理论方法的发展，这两者的目的都是为了定义动力学在功能中的作用的概念。这项研究将开发和使用的技术包括飞秒光谱学、质谱学、电子衍射(结晶学)和分子生物学。目标包括解决和研究结构与功能以及从介观到凝聚相极限的转变所涉及的动力学的重要特征。微观溶剂化、分子识别、表面识别和反应性的研究提供了一个独特的机会，在基础水平上测试大小、密度和距离受控条件下的分子相互作用，并以原子尺度的分辨率进行测试。这些研究涵盖基本的和复杂的分子系统。在这个提议中，目标是在原子运动的尺度上检查物质和生命分子的动力学性质。只有在飞秒(十亿分之一秒)的时间分辨率下，我们才能观察到这样的运动。揭示原子和分子的行为对于我们理解物质的性质和生命分子如何发挥作用是基本的，并反过来对于我们对未来材料和分子行为的潜在控制，例如通过基因识别药物。这个项目的更广泛的影响将显著影响三个主要领域：第一，对其他领域的影响，特别是材料科学、纳米科学和生物科学；第二，开发新技术以促进新技术的发展，反之亦然；对于这一特定项目，在超快成像和光学方面--其中一项进步是，超快电子结晶学的发展因其独特性而成为一项国家资源；第三，非常重视推进教育目标。多年来，加州理工学院的这群人已经有200多名研究生、博士后研究员和访问助理，其中大多数人现在处于学术、工业和教育的领先地位。该项目将确保在为工业、大学和国家实验室的职位培养未来的科学技术领导者方面产生重大影响。该项目由化学部和材料研究部共同资助。

This project will explore two main themes: 1) the application of novel diffraction techniques to examine, with atomic-scale spatial resolution, solid surfaces and materials; 2) a real-time study of solvation in the condensed phase. The intellectual merit of these research activities stem from the development of novel experimental techniques and theoretical methods, both of which are aimed at defining concepts for the role of dynamics in functions. Techniques to be developed and used in this research include femtosecond spectroscopy, mass spectrometry, electron diffraction (crystallography), and molecular biology. The objectives include resolving and studying important features of the dynamics involved in the correlation of structure to function and to the transition from the mesoscopic to the condensed-phase limit. Studies of microscopic solvation, molecular recognition, and surface recognition and reactivity offer a unique opportunity to test, on a fundamental level, molecular interactions under controlled conditions of size, density, and distance, and with atomic-scale resolution. These studies cover elementary and complex molecular systems.In this proposal, the goal is to examine the dynamical nature of matter and life molecules at the atomic scale of motion. Only with femtosecond (a millionth of a billionth of a second) time resolution can we observe such motion. The uncovering of the behavior of atoms and molecules is fundamental to our understanding of the properties of matter and to how life molecules do their function, and in turn, for our potential control of future materials and molecular behavior in, e.g., drug recognition by genes.The broader impacts of this project will significantly influence three major areas: First, the impact on other fields, in particular materials science, nanoscience, and bioscience; Second, the development of novel techniques for the advancement of new technologies, and vice versa, for this particular project, in ultrafast imaging and optics - one of these advancements, the development of ultrafast electron crystallography (UEC) constitutes, for its uniqueness, a national resource; thirdly, there is a significant emphasis on advancing educational objectives. This group at Caltech has had over the years more than 200 graduate students, post-doctoral fellows, and visiting associates, the majority of whom are now in leading academic, industrial, and educational positions. This project will assure a significant impact in preparing future leaders in science and technology for positions in industry, university, and national laboratories. This project is co-funded by the Chemistry Division and the Division of Materials Research.