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Unexpectedly high pressure for molecular dissociation in liquid hydrogen by electronic simulation.

ABSTRACT: The study of the high pressure phase diagram of hydrogen has continued with renewed effort for about one century as it remains a fundamental challenge for experimental and theoretical techniques. Here we employ an efficient molecular dynamics based on the quantum Monte Carlo method, which can describe accurately the electronic correlation and treat a large number of hydrogen atoms, allowing a realistic and reliable prediction of thermodynamic properties. We find that the molecular liquid phase is unexpectedly stable, and the transition towards a fully atomic liquid phase occurs at much higher pressure than previously believed. The old standing problem of low-temperature atomization is, therefore, still far from experimental reach.

SUBMITTER: Mazzola G

PROVIDER: S-EPMC3973041 | biostudies-literature | 2014 Mar

REPOSITORIES: biostudies-literature

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Unexpectedly high pressure for molecular dissociation in liquid hydrogen by electronic simulation.

Mazzola Guglielmo G Yunoki Seiji S Sorella Sandro S

Nature communications 20140319

The study of the high pressure phase diagram of hydrogen has continued with renewed effort for about one century as it remains a fundamental challenge for experimental and theoretical techniques. Here we employ an efficient molecular dynamics based on the quantum Monte Carlo method, which can describe accurately the electronic correlation and treat a large number of hydrogen atoms, allowing a realistic and reliable prediction of thermodynamic properties. We find that the molecular liquid phase i ...[more]

PMID: 24647280

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