High-Resolution Crystallographic Studies Using Synchrotron Radiation

纽约州立大学布法罗分校的菲利普·科彭斯得到了实验物理化学项目的支持，继续利用X射线结晶学对固体的电子结构进行研究。他的研究主要集中在以下目标：a)确定固体中的电荷密度分布；b)利用同步辐射源的可调性进行共振散射，这将允许同一元素的原子在不同的氧化状态下进行区分；c)研究晶体中分子的激发态；以及d)分析多亚晶格复合固体。将利用超低温单晶技术进行数据收集。这些实验将有助于提供必要的工具来研究一些光化学活性体系中短寿命激发态的结构。电荷分离系统很重要，因为它们直接关系到能量的转换和存储。对于这些研究的其他方面，如果我们想要弄清楚为什么固体以它们的方式堆积，那么从结晶学和理论获得的电荷密度的良好比较是必要的，并且混合价态化合物在许多催化系统、重要的技术材料和生物系统中非常重要。

Philip Coppens of the State University of New York at Buffalo has support from the Experimental Physical Chemistry Program to continue his studies of the electronic structure of solids using X-ray crystallography. His research focuses on the following objectives: a) to determine the charge density distribution in solids; b) to exploit the tunability of synchrotron sources for resonant scattering, which will allow differentiation between atoms of the same element in different oxidation states; c) to study excited states of molecules in crystals; and d) to analyze multi-sublattice composite solids. Very low-temperature single crystal techniques will be exploited for data collection. These experiments will help provide the tools necessary to study the structures of short-lived excited states in a number of photochemically active systems. The charge-separated systems are important because they are directly related to energy conversion and storage. Regarding other aspects of these studies, good comparisons of charge densities obtained from crystallography and from theory are needed if we are ever going to figure out why solids pack the way they do, and mixed valence compounds are very important in many catalytic systems, technologically important materials and biological systems.