This research program consists of several projects with a common theme, understanding the chemistry, dynamics, structures, and electronic properties of condensed materials under high pressures and, often, extremes of temperature. The research centers on five problem areas: 1. Melting and Other Phase Equilibria of Simple Solids and Solid Mixtures at High Pressures 2. A Search for Nitrogen Metal at Room Temperature 3. Unsaturated Carbon Compounds at Very High Static Pressures 4. Shock-Decomposition Chemistry of Benzene and Electronic Spectra from and behind Shock Fronts 5. X-Ray Diffraction under Extreme Conditions The emphasis is experimental. However, many of the systems they study are relatively simple in the sense that their properties can be modeled by theorists. They attempt to determine how these materials behave at high pressures with sufficient precision to test the accuracy of these models and, thereby, to contribute to improving their understanding of how materials respond to high stresses on the molecular level. //