English

Origin of superionic state in Earth's inner core

Geophysics 2026-05-28 v1 Earth and Planetary Astrophysics Materials Science Chemical Physics

Abstract

Earth's inner core (IC) serves as a reservoir for volatile elements, which significantly affects its behavior and properties. Recent studies suggest that superionicity can be observed in ice and iron hydrides under high-pressure and temperature conditions, providing an alternative understanding of the planet's interior. In this study, we demonstrated that electride formation drives the superionic state in iron hydride under IC pressure conditions. The electride stabilizes the iron lattice and provides a pathway for volatile diffusion. The coupling between lattice stability and superionicity is triggered near 100 GPa and enhanced at higher pressures. The electride-driven superionicity can also be generalized for volatiles in other rocky planetary cores. These findings provide new insights into the mechanisms of core formation and evolution of rocky planets.

Keywords

Cite

@article{arxiv.2306.07534,
  title  = {Origin of superionic state in Earth's inner core},
  author = {Ina Park and Yu He and Ho-kwang Mao and Ji Hoon Shim and Duck Young Kim},
  journal= {arXiv preprint arXiv:2306.07534},
  year   = {2026}
}

Comments

26 pages, 4 main figures and 6 supplementary figures

R2 v1 2026-06-28T11:03:35.552Z