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Center for Nonlinear Studies |
Hydrogen-rich alloys are proposed to facilitate realization of metallic hydrogen at high pressures due to a chemical precompression undergone by hydrogen in such compounds [1]. However, the effect of structure and chemical composition on the formation and properties of such materials remains purely understood. In this work, I will present synthesis and properties of hydrogen-rich alloys (superhydrides) which become thermodynamically stable at high pressures. I will review a number of our recent studies of structure, optical and vibrational properties of hydride with various compositions (of noble gases, chalcogens, simple molecules, and metals). These materials revealed a wide range of metastability holding a promise for synthesis of materials with unique physical and chemical properties for a variety of applications [2-4]. This investigation has a direct relevance for planetary interiors as the compounds synthesized in this study can exist as alternative planetary ices or mantle/core minerals. In the second part of the talk I will review the most recent investigations attempting to characterize the insulator-metal transition in hydrogen including our recent study of the optical study of hydrogen at high pressures and high temperatures [5]. 1. N. W. Ashcroft, Phys. Rev. Lett. 92, 187002 (2004). 2. A. F. Goncharov, et al., J. Chem. Phys.142, 214308 (2015). 3. A. F. Goncharov, et al., Phys. Rev. B 93, 174105 (2016). 4. V. V. Struzhkin et al., Nat. Commun., 7, 12267 (2016). 5. R. S. McWilliams et al., Phys. Rev. Lett., 116, 255501 (2016)
Host: Fedor Balakirev