Discovery of Electrides in Electron‐Rich Non‐Electride Materials via Energy Modification of Interstitial Electrons

With the discovery of electrides, many electron‐rich materials are reported to be non‐electrides due to the lack of electride characteristics. Up to date, only a few studies have been done to alter the electronic structures of these materials. In this work, through atom replacement, the energy of interstitial electrons in a non‐electride Hf₅Si₃ is successfully modified and a hitherto unknown electride Ca₃Hf₂Si₃ is obtained. It is revealed that the formation of the electride has a strong link to the neighboring cations of interstitial electrons. Moreover, an essential principle for the electride formation in the multi‐cations materials is proposed, and 34 dynamically stable ternary electrides are obtained through the proper atom replacement in 29 binary non‐electrides materials. The general realization of electrides in the electron‐rich non‐electrides can greatly expand the research scope of electrides.