High-throughput Exploration of Ternary Electrides

A class of materials that has gained community attention recently is electrides. These rare materials stabilize “free” electrons, loosely bound to a low-dimensional cavity space, which act as anions to chemically stabilize the structure. This characteristic feature makes them highly desirable for applications such as battery anodes, superconductors, and topological electronics. However, very few electrides have been synthesized due to their chemical instability; they often undergo degradation in ambient conditions. Thus, a challenge in this field is to discover electrides with higher stability. In this work ternary electrides of the chemical species A-B-C were targeted; the choice of species and the stoichiometry between them allows a vast space within which to engineer compounds with enhanced stabilities and desirable properties. Properties of interest include magnetic, electronic carrier density, and band topology. A global structure search was performed with first-principles calculations to identify stable and metastable structures for a given composition. Highly parallelized GPU-accelerated DFT codes were used to explore the vast parameter space. Our database will guide experimental synthesis efforts of new ternary electrides with multidimensional functional properties.