A stable compound of helium and sodium at high pressure
arXiv:1309.3827 · doi:10.1038/nchem.2716
Abstract
Helium is generally understood to be chemically inert and this is due to its extremely stable closed-shell electronic configuration, zero electron affinity and an unsurpassed ionization potential. It is not known to form thermodynamically stable compounds, except a few inclusion compounds. Here, using the ab initio evolutionary algorithm USPEX and subsequent high-pressure synthesis in a diamond anvil cell, we report the discovery of a thermodynamically stable compound of helium and sodium, Na2He, which has a fluorite-type structure and is stable at pressures >113 GPa. We show that the presence of He atoms causes strong electron localization and makes this material insulating. This phase is an electride, with electron pairs localized in interstices, forming eight-centre two-electron bonds within empty Na8 cubes. We also predict the existence of Na2HeO with a similar structure at pressures above 15 GPa.
References in corpus (4)
Cited by in corpus (37)
- High-Temperature Superconductivity in Alkaline and Rare Earth Polyhydrides at High Pressure: A Theoretical Perspective
- Actinium hydrides , , as high-temperature conventional superconductors
- Electronegativity and chemical hardness of the elements under pressure
- Discovering Inorganic Electrides from an Automated Computational Screening
- Novel Strongly Correlated Europium Superhydrides
- Synthesis of Xenon and Iron/Nickel intermetallic compounds at Earth's core thermodynamic conditions
- Novel high-pressure calcium carbonates
- Helium-iron compounds at terapascal pressures
- Exploring the role of electronic structure on photo-catalytic behavior of carbon-nitride polymorphs
- Magnetic borophenes from evolutionary search
- Materials under high pressure: A chemical perspective
- On the Electride Nature of Na-hP4
- Helium Induced Nitrogen Salt at High Pressure
- Computational Design of Flexible Electrides with Non-trivial Band Topology
- Prediction of pressure-induced stabilization of noble-gas-atom compounds with alkali oxides and alkali sulfides
- Pressure-dependent mechanical and thermodynamic properties of newly discovered cubic Na2He
- On the accuracy of the HSE hybrid functional to describe many-electron interactions and charge localization in semiconductors
- Old puzzle of incommensurate crystal structure of calaverite AuTe and predicted stability of novel AuTe compound
- Helium-bearing superconductor at high pressure
- Novel magnesium borides and their superconductivity
- Material design of indium based compounds: possible candidates for charge, valence, and bond disproportionation and superconductivity
- Study for material analogs of FeSb: material design for thermoelectric materials
- Partially Diffusive Helium-Silica Compound in the Deep Interiors of Giant Planets
- Unusual phase transition of layer-stacked borophene under pressure
- Novel chemistry of lithium oxides and superconducting low-pressure LiO4
- Quantum effects on plasma screening for thermonuclear reactions in laser-generated plasmas
- Prediction of the Reactivity of Argon with Xenon under High Pressure
- Phonon transport in at high pressure from a first-principles study
- Generating and grading 34 Optimized Norm-Conserving Vanderbilt Pseudopotentials for Actinides and Super Heavy Elements in the PseudoDojo
- Structural evolution of amorphous polymeric nitrogen from \textit{ab initio} molecular dynamics simulations and evolutionary search
- Helium-hydrogen immiscibility at high pressures
- Crystal Chemistry at High Pressure
- He-Mg compounds and helium-driven nonmetal transition in metallic magnesium
- Theoretical Study on the Structural and Thermodynamic Properties of U-He compounds under High Pressure
- High-pressure hybrid materials that can store hydrogen in table salt
- Unexpected Xe cations and superconductivity in Y-Xe compounds under pressure
- On stable H-C-N-O compounds at high pressure