Related papers: Metastable Ultracondensed Solid Hydrogenous Materi…
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…
In the last five years a large number of new high-temperature superconductors have been predicted and experimentally discovered among hydrogen-rich crystals, at pressures which are way too high to meet any practical application. In this…
The study of the high pressure phase diagram of hydrogen has continued with renewed effort for about one century as it remains a fundamental challenge for experimental and theoretical techniques. Here we employ an efficient molecular…
Two hydrogen-rich materials, H$_3$S and LaH$_{10}$, synthesized at megabar pressures, have revolutionized the field of condensed matter physics providing the first glimpse to the solution of the hundred-year-old problem of room temperature…
In this chapter, the physisorption of hydrogen molecules in porous materials as possible hydrogen storage systems has been reviewed. Owing to the weak interaction between H2 molecules and the adsorbent, high storage capacities are typically…
Superconductors have the potential to revolutionize technology due to their ability to have zero electrical resistance. However, superconductor materials require either low temperatures or high pressures to function in a superconductive…
Behaviours of hydrogen, such as fluidity and metallicity, are crucial for our understanding of planetary interiors and the emerging field of high-temperature superconducting hydrides. These behaviours were discovered in complex phase…
Evolutionary structure searches are used to predict stable phases with unique stoichiometries in the hydrogen-rich region of the magnesium/hydrogen phase diagram under pressure. MgH$_4$, MgH$_{12}$ and MgH$_{16}$ are found to be…
Knowledge of the behavior of hydrogen in metal hydrides is the key for understanding their electronic properties. So far, no experimental methods exist to access these properties beyond 100 GPa, where high-Tc superconductivity emerges.…
Reaching pressures in the 100 GPa range enables the synthesis of hydrogen-rich compounds, with nontraditional H stoichiometries and H sublattices, called superhydrides. Record-breaking superconductivity temperature in some superhydrides…
We develop a statistical physics theory for solid-solid phase transitions in which a metamaterial undergoes longitudinal contraction in response to increase in external tension. Such transitions, which are forbidden in thermodynamic…
We examine the molecular-atomic transition in liquid hydrogen as it relates to metallization. Pair potentials are obtained from first principles molecular dynamics and compared with potentials derived from quadratic response. The results…
Using density functional theory molecular dynamics simulations, we predict shock Hugoniot curves of precompressed methane up to 75000 K for initial densities ranging from 0.35 to 0.70 g/cc. At 4000 K, we observe the transformation into a…
The resistivity of a superconductor in its normal state plays a critical role in determining its superconducting ground state. However, measuring the resistivity of a material under high pressure has long presented a significant technical…
In recent years, the resistance signature of the high temperature superconductivity above 250 K in highly compressed hydrides (more than 100 GPa) has garnered significant attention within the condensed matter physics community. This has…
Optical properties of compressed fluid hydrogen in the region where dissociation and metallization is observed are computed by ab-initio methods and compared to recent experimental results. We confirm that above 3000 K both processes are…
The extreme pressures required to stabilize the recently discovered superhydrides represent a major obstacle to their practical application. In this paper, we propose a novel route to attain high-temperature superconductivity in hydrides at…
The highest critical temperature of superconductivity Tc has been achieved in cuprates: 133 K at ambient pressure and 164 K at high pressures. As the nature of superconductivity in these materials is still not disclosed, the prospects for a…
The extended Hubbard Hamiltonian on a bcc lattice is studied at half-filling and for a finite hopping between next-nearest-neighbours, in mean-field approximation. An ionic insulating broken-symmetry phase is predicted for any hydrogenoid…
Recently, superhydrides have been computationally identified and subsequently synthesized with a variety of metals at very high pressures. In this work, we evaluate the possibility of synthesizing superhydrides by uniquely combining…