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arXiv 1005.19852010-05-12cond-mat.mtrl-sciphysics.chem-phphysics.plasm-ph

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

Cong Wang, Yun-Jun Gu, Qi-Feng Chen, Xian-Tu He, Ping Zhang

备注：: 5 figures

英文摘要：

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.

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