Ternary Inorganic Electrides with mixed bonding

Abstract

A high-throughput screening based on first-principles calculations was performed to search for new ternary inorganic electrides. From the available materials database, we identified three new thermodynamically stable materials (Li${}_{12}$Mg${}_3$Si${}_4$, NaBa${}_2$O and Ca${}_5$Ga${}_2$N${}_4$) as potential electrides made by main group elements, in addition to the well known mayenite based electride (C12A7:$e^{-}$). Different from those conventional inorganic electrides in which the excess electrons play only the role of anions, the three new materials, resembling the electrides found in simple metals under high pressure, possess mixed ionic and metallic bonding. The interplay between two competing mechanisms, together with the different crystal packing motifs, gives rise to a variety of geometries in anionic electrons, and rich physical phenomena such as ferromagnetism, superconductivity and metal-insulator transition. Our finding here bridges the gap between electrides found at ambient and high pressure conditions.

arXiv comment10 pages, 8 figures

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Cited by in corpus (9)

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• Six-fold Excitations in Electrides
• Predicted superconductivity and superionic state in the electride Li${}_5$N under high pressure
• Stabilization mechanism of clathrate H cages in a room-temperature superconductor LaH${}_{10}$
• Metallization of hydrogen by intercalating ammonium ions in metal fcc lattices at low pressure
• Underlying mechanism of charge transfer in Li-doped MgH${}_{16}$ at high pressure
• First-principles Investigation of Electrides Derived from Sodalites
• Semiconducting Electrides Derived From Sodalite: A First-principles Study
• Origin of enhanced chemical precompression in cerium hydride CeH${}_9$