High-Resolution Crystallographic Studies Using Synchrotron Radiation

纽约州立大学布法罗分校的Philip Coppens得到了实验物理化学项目的支持，继续使用x射线晶体学研究固体的电子结构。他的研究主要集中在以下几个方面：a)确定固体中的电荷密度分布；B)利用同步加速器源共振散射的可调性，这将允许在不同氧化态的同一元素的原子之间的区分；C)研究晶体中分子的激发态；d)分析多亚点阵复合固体。极低温单晶技术将被用于数据收集。这些实验将有助于为研究许多光化学活性体系中的短寿命激发态结构提供必要的工具。电荷分离系统很重要，因为它们与能量转换和存储直接相关。关于这些研究的其他方面，如果我们想要弄清楚为什么固体会以这样的方式堆积，那么从晶体学和理论中得到的电荷密度需要进行很好的比较，混合价化合物在许多催化系统、技术上重要的材料和生物系统中都是非常重要的。

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.