Equation of state for shock compressed xenon in the ionization regime: ab initio study

TL;DR

This study uses quantum molecular dynamics and ionization corrections to accurately model the equation of state for shock-compressed xenon, aligning well with experimental data up to 160 GPa.

Contribution

It introduces a combined QMD and Saha equation approach to account for atomic ionization in xenon under shock compression, improving EOS predictions.

Findings

EOS matches experimental Hugoniot data below 160 GPa

Three ionization levels are sufficient for accurate modeling

Ionization significantly influences thermophysical properties at high pressures

Abstract

Quantum molecular dynamic (QMD) simulations have been applied to study the thermophysical properties of liquid xenon under dynamic compressions. The equation of state (EOS) obtained from QMD calculations are corrected according to Saha equation, and contributions from atomic ionization, which are of predominance in determining the EOS at high temperature and pressure, are considered. For the pressures below 160 GPa, the necessity in accounting for the atomic ionization has been demonstrated by the Hugoniot curve, which shows excellent agreement with previous experimental measurements, and three levels of ionization have been proved to be sufficient at this stage.