9412187 Nicol The objective of this proposed work is to measure properties of materials at moderately high pressures to tens of gigapascals (GPa) with sufficient precision to test the accuracy of theoretical models and translate the understanding into new materials. Specific areas of research outlined in the proposal include: (1) characterizing the photochemistry, chemistry and phase diagram of sulfur to approximately 20 GPa; (2) developing x-ray diffraction techniques at the Stanford Synchrotron Radiation Laboratory (SSRL) for high temperature-high pressure techniques; (3) determining crystal structures and sound speeds to 20 GPa and 1000 degrees kelvin for the same oriented oxide crystal and structures for oxygen, sulfur, and nitroanilines; (4) defining intra-and inter-molecular perturbations on the structures and stabilities of nitroanilines and nitroaromatics related to energetic materials and (5) determining the conditions, mechanisms and products of reactions which limit the stabilities of unsaturated carbon compounds in the 5-15 GPa range. %%% The goal of this proposed study is to explore the high-pressure synthesis of novel materials. These fundamental chemistry and physics studies under high pressure, to include vibrational dynamics, energetics and structures of condensed-phase systems, will lead to materials developments in areas of technological interest such as energetic materials, polymers, and molecular materials such as diamond and fullerenes.
