First-principle study of solid neon under high compression

Crystal structure, metallization and equation of state of solid neon at extremely high pressures are studied with first-principle simulations. Density functional (DFT) calculations based on the generalized gradient approximation (GGA) show that solid neon adopts the fcc phase up to pressures of 256 TPa. Solid fcc neon exhibits a direct band gap at low densities and an indirect band gap at high densities. The band gap of solid fcc neon closes at a density of 74.9 g/cm3 and a pressure of 142 TPa, which is about 8% larger than the prediction of linear combination of Gaussian-type orbital (LCGTO) [3]. Further, GW approximation calculations predict that the metallization density and metallization pressure of solid fcc neon are 83.1 g/cm3 and 176 TPa, respectively. Finally, the equation of state of solid neon up to 3800 TPa are calculated and fit functions are presented.