Uncertainty-Aware Equation of State Development for Nickel

An uncertainty-aware multiphase equation of state (EOS) model for nickel has been developed. The current EOS is built using an integrated training dataset that includes the latest high-compression Z-shot data, recent warm-dense matter regime DFT-MD calculations, and a wide range of literature data. High-accuracy diamond-anvil cell x-ray diffraction experiments performed at the Japan Synchrotron Radiation Research Institute are used to constrain the EOS model at pressures above 300 GPa. The EOS electrical response is constrained by both liquid/solid isobaric electrical conductivity data within a Lee-More-Desjarlais model. The critical vapor region is bounded using experimental vaporization measurements as well as a suite of low-density (1-5 g/cc) DFT-MD calculations. The EOS liquid regime and melt-boundaries are trained on liquid Hugoniot, melt, and speed-of sound measurements.