A note on the metallization of compressed liquid hydrogen

TL;DR

This paper investigates the transition of liquid hydrogen from molecular to atomic form and its implications for metallization, using first-principles simulations to inform phase diagrams and experimental strategies.

Contribution

It introduces a new analysis of covalent bonding under extreme conditions and proposes experimental methods to achieve hydrogen metallization at lower pressures.

Findings

Insights into covalent bonding in high-pressure hydrogen

A schematic phase diagram for dissociation and metallization

Proposals for experimental approaches to reduce metallization pressure

Abstract

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 provide insight into the nature of covalent bonding under extreme conditions. Based on this analysis, we construct a schematic dissociation-metallization phase diagram and suggest experimental approaches that should significantly reduce the pressures necessary for the realization of the elusive metallic phase of hydrogen.