A series of experimental studies of simple molecular systems to pressures above 300 GPa (3 megabars) over a broad range of temperatures will be carried out in this project. The research takes advantage of numerous developments in diamond-anvil cell techniques, including advances in analytical methods that utilize synchrotron x-radiation, optical spectroscopy, and transport probes. Hydrogen-dominant simple molecular solids, alloys, and selected elements will be examined to search for metallization and superconductivity. The crystal structures and electronic structures of newly discovered high-pressure phases will be determined using synchrotron x-ray techniques. Newly discovered high-pressure radiation chemistry will be explored. By improving our understanding of fundamental interactions in condensed matter, the project will impact areas of the physical sciences as diverse as nanoscience to the interiors of giant planets. The proposed work will showcase the synergy between fundamental science and new technologies, including addressing future energy problems. The project will advance technology necessary for studying matter under more extreme conditions. The research will seek to enhance capabilities major national facilities, and will train post-doctoral fellows as well as high school students, undergraduates, graduate students, and visiting investigators.
Non-technical This project will explore the nature of matter through experimental studies of simple molecular substances subjected to pressures to above 3 megabars (3 million times atmospheric pressure) over a broad range of temperatures from near absolute zero to many thousands of degrees. The project takes advantage of numerous recent developments in the ability both to subject materials to these extreme conditions and to probe samples under those conditions with synchrotron x-rays, lasers, and new magnetic and electrical methods. Hydrogen-rich molecules will be transformed into new kinds of metals and superconductors, and the nature of metallic hydrogen, a predicted entirely new state of matter with exotic properties, will be explored. The dramatic changes in crystal structure and chemical bonding expected for materials under extreme conditions will be determined using a variety of synchrotron x-ray methods. The results impact materials science, nanoscience, planetary science, and astrophysics. The work will lead to development of new energetic materials, novel superconductors, gas storage materials, and superhard materials. The research will enhance capabilities at major national facilities, and will train high school students, undergraduates, graduate students, postdoctoral associates, and senior scientists. Impacts on both science and society broadly are therefore expected.
The research program improved our understanding of fundamental interactions in condensed matter, and as a consequence, impacted areas of the physical sciences from materials science at the nanoscale to the interiors of giant planets. The work showcased the synergy between fundamental science and new technologies, and led to the development of new energetic materials, superconductors, gas storage materials, and superhard materials. As such these studies of simple molecular materials under extreme conditions are expected to have long-term impacts for addressing future energy problems. The project leveraged recent developments in infrastructure at major central facilities supported by the US government (e.g., synchrotron x-ray and neutron sources). The research enhanced capabilities at those national facilities with the development of new experimental techniques for the broader community and training of new scientists at these facilities. A wide cross-section of participants benefitted from the work, from high school students and undergraduates in our internship programs, to graduate students, postdoctoral associates and visiting investigators. As such, the project took advantage of existing infrastructure to prepare young scientists for careers in academia, national laboratories, and industry. The results and implications of the proposed work were featured in popular articles and lectures. By advancing fundamental science with newly developed techniques, the potential for materials applications, the training of new scientists, and educating the public, the proposed work contributed to both science and society broadly.
