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arXiv · 0802.1316

Stable liquid Hydrogen at high pressure by a novel ab-initio molecular dynamics

Claudio Attaccalite·Sandro Sorella
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Abstract

We introduce an efficient scheme for the molecular dynamics of electronic systems by means of quantum Monte Carlo. The evaluation of the (Born-Oppenheimer) forces acting on the ionic positions is achieved by two main ingredients: i) the forces are computed with finite and small variance, which allows the simulation of a large number of atoms, ii) the statistical noise corresponding to the forces is used to drive the dynamics at finite temperature by means of an appropriate Langevin dynamics. A first application to the high-density phase of Hydrogen is given, supporting the stability of the liquid phase at \simeq 300GPa and \simeq 400K.

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Claudio Attaccalite, Sandro Sorella. 2008-02-10. Stable liquid Hydrogen at high pressure by a novel ab-initio molecular dynamics. https://doi.org/10.1103/physrevlett.100.114501

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