Ab initio study of shock compressed oxygen

TL;DR

This study uses quantum molecular dynamics to investigate shock compressed oxygen, revealing molecular dissociation, electronic structure changes, and a nonmetal-metal transition consistent with experimental data.

Contribution

It introduces ab initio simulations to analyze shock compressed oxygen, including electronic and optical property changes under high pressure.

Findings

Hugoniot points match experimental data

Molecular dissociation occurs at high pressure

Nonmetal-metal transition around 30-50 GPa

Abstract

Quantum molecular dynamic simulations are introduced to study the shock compressed oxygen. The principal Hugoniot points derived from the equation of state agree well with the available experimental data. With the increase of pressure, molecular dissociation is observed. Electron spin polarization determines the electronic structure of the system under low pressure, while it is suppressed around 30 $\sim$ 50 GPa. Particularly, nonmetal-metal transition is taken into account, which also occurs at about 30 $\sim$ 50 GPa. In addition, the optical properties of shock compressed oxygen are also discussed.