Orthorhombic ABC Semiconductors as Antiferroelectrics

We use a first-principles rational-design approach to identify a previously unrecognized class of antiferroelectric materials in the 𝑃⁢𝑛⁢𝑚⁢𝑎 MgSrSi structure type. The MgSrSi structure type can be described in terms of antipolar distortions of the nonpolar 𝑃⁢6₃/𝑚⁢𝑚⁢𝑐 ZrBeSi structure type, and we find many members of this structure type are close in energy to the related polar 𝑃⁢6₃⁢𝑚⁢𝑐 LiGaGe structure type, which includes many members we predict to be ferroelectric. We highlight known 𝐴⁢𝐵⁢𝐶 combinations in which this energy difference is comparable to the antiferroelectric-ferroelectric switching barrier of PbZrO₃. We calculate structural parameters and relative energies for all three structure types, both for reported and as-yet hypothetical representatives of this class. Our results provide guidance for the experimental realization and further investigation of high-performance materials suitable for practical applications.