Understanding the behaviour of materials at high pressures and temperatures is directly linked to our understanding of planetary interiors. In particular, of great interest is the equation of state, the dissociation and metallization pressure of dense liquid hydrogen and mixtures. Since a few decades the link between the uncertainty of the equation of states and the internal structure of Jupiter and other gaseous planets have been investigated. Unfortunately, this kind of systems remains a challenge for Density Functional Theory (DFT) simulations, which are used to construct ab-initio Jupiter models.
We present a new Quantum Monte Carlo (QMC) calculation for hydrogen and hydrogen-helium mixture. We employ a novel accelerated molecular dynamics scheme and are able to perform large scale simulations much longer than the equilibration time. In particular we report the first QMC molecular dynamics simulation with an hydrogen/helium mixture. We employ a 128 particle system with an hydrogen/helium ratio close to the protosolar value.
We compare our equation of state with the ones coming from DFT simulations and our prediction for the metallization pressure at Jupiter’s conditions with experiments. We discuss the implications for Jupiter's internal structure.
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