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arXiv · 1905.09541

Dynamical continuum simulation of condensed matter from first-principles

Oliver Strickson·Nikos Nikiforakis·Emilio Artacho
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Abstract

Macroscale continuum mechanics simulations rely on material properties stemming from the microscale, which are normally described using phenomenological equations of state (EOS). A method is proposed for the automatic generation of first-principles unconstrained EOSs using a Gaussian process on a set of ab initio molecular dynamics simulations, thereby closing the continuum equations. We illustrate it on a hyperelasticity simulation of bulk silicon using density-functional theory (DFT), following the dynamics of shock waves after a cylindrical region is instantaneously heated.

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Oliver Strickson, Nikos Nikiforakis, Emilio Artacho. 2019-05-23. Dynamical continuum simulation of condensed matter from first-principles. https://doi.org/10.1103/physrevresearch.1.033199

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