Prediction of a Mobile Solid State in Dense Hydrogen under High Pressures

Abstract

Solid rigidity and liquid-scale mobility are thought incompatible in elemental substances. One cannot have an elemental solid that is long-range positionally ordered wherein the atoms flow like in a liquid simultaneously. The only exception might be the hypothetical supersolid state of 4He. In this work, we demonstrate that such exotic state could exist even in the classical regime. Using ab initio molecular dynamics (AIMD) and ab initio path integral molecular dynamics (AI-PIMD), a novel state of dense hydrogen which simultaneously has both long-range spatial ordering and liquid-scale atomic mobility is discovered at 1~1.5 TPa (1 TPa=10000000 atmospheric pressures). The features distinct from a normal solid and liquid are carefully characterized, with the stability and melting behavior are investigated. Extensive AI-PIMD simulations further revealed that this state might be (meta-)stable even at ultra-low temperatures, suggesting an emerging candidate for an alternative type of supersolid state in dense metallic hydrogen.

arXiv comment26 pages, 9 figures

References in corpus (14)

• A superconductor to superfluid phase transition in liquid metallic hydrogen
• Nuclear Quantum Effects and Nonlocal Exchange-Correlation Functionals Applied to Liquid Hydrogen at High Pressure
• Quantum simulation of low-temperature metallic liquid hydrogen
• Towards a Predictive First-Principles Description of Solid Molecular Hydrogen with Density-Functional Theory
• Equation of state of metallic hydrogen from Coupled Electron-Ion Monte Carlo simulations
• Rubidium Polyhydrides Under Pressure: Emergence of the Linear H3- Anion
• Proton Transfer in Phase IV of Solid Hydrogen and Deuterium
• High-pressure behavior of dense hydrogen up to 3.5 TPa from density functional theory calculations
• A liquid-solid critical point in a simple monatomic system
• Lattice stability and high pressure melting mechanism of dense hydrogen up to 1.5 TPa
• Predicted reentrant melting of dense hydrogen at ultra-high pressures
• Appraisal of the realistic accuracy of Molecular dynamics of high pressure hydrogen
• Theory of high pressure hydrogen, made simple
• Accelerating ab initio path integral molecular dynamics with multilevel sampling of potential surface

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• Full Temperature-Dependent Potential and Anharmonicity in Metallic Hydrogen: Colossal NQE and the Consequences
• Dynamic phase transition theory
• Appraising the absolute limits of nanotubes and nanospheres to preserve high-pressure materials