2015/03/13 by Jeremy McMinis, Raymond C. Clay, Donghwa Lee +1 · 1 citation
Earth and Planetary Sciences · Physics and Astronomy · Materials Science · #High-pressure geophysics and materials #Advanced Chemical Physics Studies #Diamond and Carbon-based Materials Research
paper · doi:10.1103/physrevlett.114.105305
openalex publication_date 2015/03/13 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
The metallization of high-pressure hydrogen, together with the associated molecular to atomic transition, is one of the most important problems in the field of high-pressure physics. It is also currently a matter of intense debate due to the existence of conflicting experimental reports on the observation of metallic hydrogen on a diamond-anvil cell. Theoretical calculations have typically relied on a mean-field description of electronic correlation through density functional theory, a theory with well-known limitations in the description of metal-insulator transitions. In fact, the predictions of the pressure-driven dissociation of molecules in high-pressure hydrogen by density functional theory is strongly affected by the chosen exchange-correlation functional. In this Letter, we use quantum Monte Carlo calculations to study the molecular to atomic transition in hydrogen. We obtain a transition pressure of 447(3) GPa, in excellent agreement with the best experimental estimate of the transition 450 GPa based on an extrapolation to zero band gap from experimental measurements. Additionally, we find that C2/c is stable almost up to the molecular to atomic transition, in contrast to previous density functional theory (DFT) and DFT+quantum Monte Carlo studies which predict large stability regimes for intermediary molecular phases.