title: Distinct metallization and atomization transitions in dense liquid hydrogen.
abstract: We perform molecular dynamics simulations driven by accurate quantum Monte Carlo forces on dense liquid hydrogen. There is a recent report of a complete atomization transition between a mixed molecular-atomic liquid and a completely dissociated fluid in an almost unaccessible pressure range [Nat. Commun. 5, 3487 (2014)]. Here, instead, we identify a different transition between the fully molecular liquid and the mixed-atomic fluid at ∼400  GPa, i.e., in a much more interesting pressure range. We provide numerical evidence supporting the metallic behavior of this intermediate phase. Therefore, we predict that the metallization at finite temperature occurs in this partially dissociated molecular fluid, well before the complete atomization of the liquid. At high temperature this first-order transition becomes a crossover, in very good agreement with the experimental observation. Several systematic tests supporting the quality of our large scale calculations are also reported.
authors: International School for Advanced Studies (SISSA), and CRS Democritos, CNR-INFM, -Via Bonomea 265, I-34136 Trieste, Italy.
authors: Guglielmo
authors: G
authors: Mazzola
authors: International School for Advanced Studies (SISSA), and CRS Democritos, CNR-INFM, -Via Bonomea 265, I-34136 Trieste, Italy.
authors: Sandro
authors: S
authors: Sorella