Single crystal x-ray crystallography is the most powerful analytical method for structure determination of solids. In synthetic inorganic, organic, bioinorganic and organometallic chemistry, single crystal x-ray diffraction is an invaluable tool to characterize molecular structure. The information gained from the knowledge of the molecular composition and structure helps to develop new reactions of potentially general interest in catalysis or synthesis. This award from the Chemistry Shared Instrumentation Program will help the Department of Chemistry at the University of Delaware acquire a Single Crystal X-ray Diffraction System. Among the areas of chemical reserach that will be enhanced by the acquisition are the following: 1. Arsenic and Antimony-Based Clusters of the Early Transition Metal Elements 2. New Metal Complexes of Energetic Ambidentate Ligands 3. Binuclear Transition Metal Complexes 4. Coordination Chemistry of Ambidentate Ligands 5. Preparation of Novel Pyrazolo-fused Heterocycles 6. High-Tc Superconductivity/Structure Relationships in Perovskite-Related Oxides of Nickel