Distinct metallization and atomization transitions in dense liquid hydrogen

Abstract

We perform molecular dynamics simulations driven by accurate Quantum Monte Carlo forces on dense liquid hydrogen. Recently it has been reported a complete atomization transition between a mixed-atomic liquid and a completely dissociated fluid in an almost unaccessible pressure range {[\emph{Nat. Commun.} {\bf 5}, 3487 (2014)]}. Here instead, in a much more interesting pressure range, we identify a different transition between the fully molecular liquid and the mixed-atomic fluid at $\sim$ 400 GPa, with numerical evidence supporting its metallic behavior. Therefore we predict that the metallization at finite temperature occurs in this partially dissociated molecular fluid, well before the complete atomization of the liquid. At high temperature this first-order transition becomes a crossover, in very good agreement with the experimental observation. Several systematic tests supporting the quality of our large scale calculations are also reported.

References in corpus (16)

• Quantum ESPRESSO: a modular and open-source software project for quantum simulations of materials
• An Efficient and Accurate Car-Parrinello-like Approach to Born-Oppenheimer Molecular Dynamics
• A quantum fluid of metallic hydrogen suggested by first-principles calculations
• Nuclear Quantum Effects and Nonlocal Exchange-Correlation Functionals Applied to Liquid Hydrogen at High Pressure
• Stable liquid Hydrogen at high pressure by a novel ab-initio molecular dynamics
• Diffusion Monte Carlo with lattice regularization
• Structure and phase boundaries of compressed liquid hydrogen
• Algorithmic differentiation and the calculation of forces by quantum Monte Carlo
• Spectroscopic Studies of the Vibrational and Electronic Properties of Solid Hydrogen to 285 GPa
• Resonating valence bond wave function with molecular orbitals: Application to first-row molecules
• Fate of density functional theory in high-pressure solid hydrogen
• Unexpectedly high pressure for molecular dissociation in liquid hydrogen by a reliable electronic simulation
• Unconventional metal-insulator transition in two dimensions
• Molecular properties by Quantum Monte Carlo: an investigation on the role of the wave function ansatz and the basis set in the water molecule
• Finite temperature electronic simulations beyond the Born-Oppenheimer approximation
• Free energy methods in Coupled Electron Ion Monte Carlo

Cited by in corpus (21)

• The Uniform Electron Gas at Warm Dense Matter Conditions
• A First-order Phase Transition to Metallic Hydrogen
• Theory of Finite Size Effects for Electronic Quantum Monte Carlo Calculations of Liquids and Solids
• Phase diagram of hydrogen and a hydrogen-helium mixture at planetary conditions by Quantum Monte Carlo simulations
• First principles simulations of dense hydrogen
• Boosting the accuracy and speed of quantum Monte Carlo: size-consistency and time-step
• Ab-initio molecular dynamics simulation of liquid water by Quantum Monte Carlo
• TurboRVB: a many-body toolkit for {\it ab initio} electronic simulations by quantum Monte Carlo
• Evidence for Stable Square Ice from Quantum Monte Carlo
• Benchmarking Hydrogen-Helium Mixtures with QMC: Energetics, Pressures, and Forces
• Toward Accurate Adsorption Energetics on Clay Surfaces
• Thermodynamic anomalies and three distinct liquid-liquid transitions in warm dense liquid hydrogen
• Hydration of NH${}_4^{+}$ in Water: Bifurcated Hydrogen Bonding Structures and Fast Rotational Dynamics
• Accelerated ab-initio Molecular Dynamics: probing the weak dispersive forces in dense liquid hydrogen
• Predicted reentrant melting of dense hydrogen at ultra-high pressures
• Geminal embedding scheme for optimal atomic basis set construction in correlated calculations
• Isotope quantum effects in the metallization transition in liquid hydrogen
• Non-adiabatic effects and exciton-like states during insulator-to-metal transition in warm dense hydrogen
• Electron localization properties in high pressure hydrogen at the liquid-liquid phase transition by Coupled Electron-Ion Monte Carlo
• Metal-Insulator Transition of Solid Hydrogen by the Antisymmetric Shadow Wave Function
• Insulator-metal transition in liquid hydrogen and deuterium