# Two-Dimensional Hydrogen Structure at Ultra-High Pressure

## TL;DR

This paper presents a new computational method combining Quantum Monte Carlo and ab-initio Molecular Dynamics to study the structure of two-dimensional hydrogen at ultra-high pressures, revealing metallization at specific conditions.

## Contribution

A novel simulation approach is developed for accurately modeling 2D hydrogen structures under extreme pressures.

## Key findings

- Metallization occurs at r_s ≈ 1.1
- Transition from molecular to atomic phase at high pressure
- Estimated pressure for metallization is 1000 GPa

## Abstract

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 layer of hydrogen at $T=0~\text{K}$ and high densities. We find that metallization is to be expected at $r_s \approx 1.1$, with an estimated pressure of $1.0\cdot10^3~a_0~\text{GPa}$, changing from a graphene molecular lattice to an atomic phase.