Interplay of anionic quasi-atom and interstitial point defects in electrides: abnormal interstice occupation and colossal charge state of point defects in dense FCC-lithium

Abstract

Electrides are an emerging class of materials with highly-localized electrons in the interstices of a crystal that behave as anions. The presence of these unusual interstitial quasi-atom (ISQ) electrons leads to interesting physical and chemical properties, and wide potential applications for this new class of materials. Crystal defects often have a crucial influence on the properties of materials. Introducing impurities has been proved to be an effective approach to improve the properties of a material and to expand its applications. However, the interactions between the anionic ISQs and the crystal defects in electrides are as yet unknown. Here, dense FCC-Li was employed as an archetype to explore the interplay between anionic ISQs and interstitial impurity atoms in this electride. This work reveals a strong coupling among the interstitial impurity atoms, the ISQs, and the matrix Li atoms near to the defects. This complex interplay and interaction mainly manifest as the unexpected tetrahedral interstitial occupation of impurity atoms and the enhancement of electron localization in the interstices. Moreover, the Be impurity occupying the octahedral interstice shows the highest negative charge state (Be8-) discovered thus far. These results demonstrate the rich chemistry and physics of this emerging material, and provide a new basis for enriching their variants for a wide range of applications.

arXiv comment23 pages, 13 figures

References in corpus (6)

• Accurate and efficient algorithm for Bader charge integration
• Transparent dense sodium
• Superconductivity in Li6P electride
• High-Throughput Identification of Electrides from all Known Inorganic Materials
• Discovering Inorganic Electrides from an Automated Computational Screening
• Predicted novel insulating electride compound between alkali metals lithium and sodium under high pressure

Cited by in corpus (9)

• Predicted superconductivity and superionic state in the electride Li${}_5$N under high pressure
• Prediction of anomalous LA-TA splitting in electrides
• Simultaneous Superconducting and Topological Properties in Mg-Li Electrides at High Pressures
• Universal Metallic Surface States in Electride
• He-Mg compounds and helium-driven nonmetal transition in metallic magnesium
• Rational regulation strategies of interstitial localized electrons in electride: A density functional theory study
• Distinctive Electronic Characteristics and Ultra-high Thermoelectric Power Factor in Be-Fe Intermetallics
• Hyperbolic Dispersion and Low-Frequency Plasmons in Electrides
• Pressure induced Structure Change and Anomalies in Thermodynamic Quantities and Transport Properties in Liquid Lithium Hydride