Investigation of the Equation of State for GeO₂ Glass at High Pressure by AIMD Simulation

Abstract The equation of state (EOS) for non-crystalline materials (NCM) is critical to Earth and planetary science because much of the Earth is in a liquid state, such as the magma ocean and the liquid iron outer core. While accurate density measurements of NCM at high pressure remain a challenge, it is known that ab initio molecular dynamics (AIMD) simulations can provide not only the atomic structure of NCM under pressure, but also the EOS information between volume and external pressure. So far, a detailed comparison of the AIMD results with the experimental data is scarce. In this article, we report an AIMD study on the EOS of network-forming GeO 2 glass under different pseudopotentials with relatively large simulation boxes. The pressure-induced collapse of the tetrahedral network in GeO 2 glass can be addressed.