Document Type
Article
Publication Date
9-2-2021
Publication Title
National Science Review
Volume
9
Issue
7
First page number:
1
Last page number:
8
Abstract
Hydrogen and helium are known to play crucial roles in geological and astrophysical environments; however, they are inert toward each other across wide pressure-temperature (P-T) conditions. Given their prominent presence and influence on the formation and evolution of celestial bodies, it is of fundamental interest to explore the nature of interactions between hydrogen and helium. Using an advanced crystal structure search method, we have identified a quaternary compound FeO2H2He stabilized in a wide range of P-T conditions. Ab initio molecular dynamics simulations further reveal a novel superionic state of FeO2H2He hosting liquid-like diffusive hydrogen in the FeO2He sublattice, creating a conducive environment for H-He chemical association, at P-T conditions corresponding to the Earth's lowest mantle regions. To our surprise, this chemically facilitated coalescence of otherwise immiscible molecular species highlights a promising avenue for exploring this long-sought but hitherto unattainable state of matter. This finding raises strong prospects for exotic H-He mixtures inside Earth and possibly also in other astronomical bodies.
Keywords
high pressure; crystal structure; molecular dynamics; hydrogen-helium chemistry
Disciplines
Astrophysics and Astronomy | Physics
File Format
File Size
497 KB
Language
English
Rights
IN COPYRIGHT. For more information about this rights statement, please visit http://rightsstatements.org/vocab/InC/1.0/
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.
Repository Citation
Zhang, J.,
Liu, H.,
Ma, Y.,
Chen, C.
(2021).
Direct H-He Chemical Association in Superionic FeO2H2He at Deep-Earth Conditions.
National Science Review, 9(7),
1-8.
http://dx.doi.org/10.1093/nsr/nwab168
