No "Evidence for a new phase of dense hydrogen above 325 GPa"

TL;DR

This paper critically examines recent claims of a phase transition to metallic hydrogen above 325 GPa, concluding that the evidence does not support the existence of a new dense hydrogen phase at that pressure.

Contribution

The authors provide a detailed analysis challenging prior experimental claims, clarifying that there is no evidence for a new phase of dense hydrogen above 325 GPa.

Findings

No evidence for phase transition at 325 GPa

Previous data misinterpreted as a phase change

Supports the need for further investigation

Abstract

In recent years there has been intense experimental activity to observe solid metallic hydrogen. Wigner and Huntington predicted that under extreme pressures insulating molecular hydrogen would dissociate and transition to atomic metallic hydrogen. Recently Dalladay-Simpson, Howie, and Gregoryanz reported a phase transition to an insulating phase in molecular hydrogen at a pressure of 325 GPa and 300 K. Because of its scientific importance we have scrutinized their experimental evidence to determine if their claim is justified. Based on our analysis, we conclude that they have misinterpreted their data: there is no evidence for a phase transition at 325 GPa.