Semimetal He-rich compounds at terapascal pressures
Phys. Rev. B 114, 034114 – Published 27 July, 2026
DOI: https://doi.org/10.1103/fb4n-y594
Abstract
Helium, which is on par with neon, is one of the most inert elements and most difficult elements for metallization in the periodic table. It requires more than 30 TPa to transit to an indirect metal. Here, via an ab initio evolutionary algorithm, we predict a semimetal helium–oxygen compound, , which stabilizes at 5.74 TPa with topological nodal lines in its band structure. Further analysis revealed definite chemical bonding between the He and O atoms. Since helium and oxygen exist widely in the white dwarfs, is quite important for understanding and modeling celestial bodies.
