Phase Dependence of Noble-Gas Solubility in Metallic Hydrogen

Determine whether the solubility of noble gases (He, Ne, Ar, Kr, Xe) in metallic hydrogen at giant-planet interior conditions is intrinsically phase dependent between crystalline metallic hydrogen and liquid metallic hydrogen.

Background

Planetary interiors exhibit substantial thermal gradients, so metallic hydrogen may occur in both crystalline and liquid phases depending on depth and temperature. Prior theoretical work largely focused on hydrogen–helium immiscibility and dissolution of core materials, with comparatively scarce, systematic studies of heavier noble gases (Ne, Ar, Kr, Xe) in metallic hydrogen.

Against this backdrop, a key unresolved issue is whether noble-gas solubility depends intrinsically on the phase state of metallic hydrogen under extreme pressure–temperature conditions relevant to giant planets. Addressing this requires a unified thermodynamic framework that treats impurities consistently in both solid and liquid metallic hydrogen.