P-V-T Equation of State for Periclase

TL;DR

This paper compiles extensive experimental data to develop a comprehensive P-V-T equation of state for periclase (MgO), fitting multiple models to cover a wide pressure and temperature range with consistent parameters.

Contribution

It presents the first complete P-V-T description of MgO by integrating all previous experimental data and fitting multiple EoS models for the first time.

Findings

All three EoS models are consistent across the data range.

The RMS misfit for pressure is below 0.4 GPa for all models.

The Garai EoS has the lowest RMS misfit for volume and temperature.

Abstract

Collecting the complete data set of previous experiments on periclase, covering a pressure and temperature range of 0-141.8 GPa and 100-3031 K respectively, the first comprehensive P-V-T description of MgO is presented comprising all previous experiments. The P-V-T EoS of Birch-Murnaghan, Rydberg-Vinet and Garai are determined by unrestricted fitting. The three EoSs are consistent and a unique set of parameters is able to cover the entire pressure and temperature range. The RMS misfits for the pressure are 0.371 GPa, 0.381 GPa and 0.396 GPa for the Garai, Birch-Murnaghan and Rydberg-Vinet EoSs. The RMS misfits for the volume and the temperature are 0.018 cm3 and 60.3 K for the EoS of Garai.