Effects of thermal exchange–correlation functional on thermodynamic quantities of warm dense beryllium

We report thermodynamic properties, including equation of state, principal Hugoniot, heat capacity, and Grüneisen parameter, for beryllium under density–temperature conditions of ρ = 3.0–9.0 g/cm3 and T = 5–10 000 eV, using an extended first-principles molecular dynamics method together with finite-temperature exchange–correlation functionals. Compared with zero-temperature exchange–correlation models, our results exhibit appreciable differences of about 3% in modeling the equation of state. Thermal excitations of K-shell electrons, delocalization of wave functions, and the merging of energy bands for beryllium along the Hugoniot curve are also presented. In addition to the application of these thermodynamic data to inertial confinement fusion and high-energy-density physics, our results may also serve as useful benchmarks for investigating thermal exchange–correlation effects on thermodynamic properties of warm dense matter, and further help to elucidate the mechanisms of inner-shell electron excitation.