Discovering Inorganic Electrides from an Automated Computational Screening

Abstract: Electrides, with their excess electrons distributed in crystal cavities playing the role of anions, exhibit a variety of unique properties which make these materials desirable for many applications in catalysis, nonlinear optics and electron emission. While the first electride was discovered almost four decades ago, only few electride materials are known today, which limits our fundamental understanding as well as the practical use of these exotic materials. In this work, we propose an automated computational screening scheme to search for interstitial electrons and quantify their distributions inside the crystal cavities and energy space. Applying this scheme to all candidate materials in the Inorganic Crystal Structure Database (ICSD), we report the identification of 167 potential electride materials. This work significantly increases the current library of electride materials, which enables an in-depth investigation of their chemistry-structure-property relations and opens new avenues for future electride design.