Related papers: Distinct metallization and atomization transitions…
We present results and discuss methods for computing the melting temperature of dense molecular hydrogen using a machine learned model trained on quantum Monte Carlo data. In this newly trained model, we emphasize the importance of accurate…
We simulate high-pressure hydrogen in its liquid phase close to molecular dissociation using a machine-learned interatomic potential. The model is trained with density functional theory (DFT) forces and energies, with the…
Experiments and computer simulations have shown that the melt-ing temperature of solid hydrogen drops with pressure above about 65 GPa, suggesting that a liquid state might exist at low temperatures. It has also been suggested that this low…
The molecular-to-atomic liquid-liquid transition (LLT) in high-pressure hydrogen is a fundamental topic touching domains from planetary science to materials modeling. Yet, the nature of the LLT is still under debate. To resolve it,…
For a long time, there have been huge discrepancies between different models and experiments concerning the liquid-liquid phase transition (LLPT) in dense hydrogen. In this work, we present the results of extensive calculations of the LLPT…
Metallic hydrogen is expected to exhibit remarkable physics. Of particular interest in this work is the possibility of high-temperature superconductivity. Comparing calculations of the superconducting critical temperatures of the solid…
Non-monotonous changes in velocity autocorrelations across the transformation from molecular to atomic fluid in hydrogen under pressure are studied by ab initio molecular dynamics simulations at the temperature 2500 K. We report diffusion…
We present an accurate study of the static-nucleus electronic energy band gap of solid molecular hydrogen at high pressure. The excitonic and quasiparticle gaps of the $C2/c$, $Pc$, $Pbcn$, and $P6_3/m$ structures at pressures of 250, 300,…
Temperature-driven polyamorphism has been reported in various supercooled liquids and glasses. The dynamical and structural routes followed by the system during such crossovers are however not universal and appear to be related to intrinsic…
We survey the phase diagram of high-pressure molecular hydrogen with path integral molecular dynamics using a machine-learned interatomic potential trained with Quantum Monte Carlo forces and energies. Besides the HCP and C2/c-24 phases, we…
We introduce a novel method that combines the accuracy of Quantum Monte Carlo simulations with ab-initio Molecular Dynamics, in the spirit of Car-Parrinello. This method is then used for investigating the structure of a two-dimensional…
The molecular phase of hydrogen converts to the atomic metallic phase at high pressures estimated usually as 300 - 500 GPa. We analyze the decay of metallic phase as the pressure is relieved below the transition one. The metallic state is…
Hydrogen has been the essential element in the development of atomic and molecular physics1). Moving to the properties of dense hydrogen has appeared a good deal more complex than originally thought by Wigner and Hungtinton in their seminal…
Ab initio molecular dynamic method within the framework of density functional theory is applied to analyze the structural and electronic properties of crystalline molecular hydrogen at temperature 100\,K. Pressure, pair correlation function…
We use numerical simulation to examine the possibility of a reversible liquid-liquid transition in supercooled water and related systems. In particular, for two atomistic models of water, we have computed free energies as functions of…
We investigate the dissociation and ionization equilibria of deuterium fluid over a wide range of temperatures and densities. The partition functions for molecular and atomic species are evaluated, in a statistical-mechanically consistent…
We calculate the melting line of atomic hydrogen and deuterium up to 900 GPa with path-integral Monte Carlo using a machine-learned interatomic potential. We improve upon previous simulations of melting by treating the electrons with…
Molecular hydrogen was pressurized in a diamond anvil cell at temperatures between 5 and 83 K. At a sufficiently high pressure, estimated to be between 477 to 491 GPa, hydrogen became metallic, determined by its reflectance in the near…
We present a new Monte Carlo method which couples Path Integral for finite temperature protons with Quantum Monte Carlo for ground state electrons, and we apply it to metallic hydrogen for pressures beyond molecular dissociation. We report…
We present a study of hydrogen at pressures higher than molecular dissociation using the Coupled Electron-Ion Monte Carlo method. These calculations use the accurate Reptation Quantum Monte Carlo method to estimate the electronic energy and…