High-throughput First-principles Screening of the Layered Magnetic Double-Perovskites Cs₄MSb₂X₁₂

Compared to the three-dimensional halide perovskites, the layered perovskites can exhibit better air-stability and more flexible optoelectronic properties. Among them, Cs₄CuSb₂Cl₁₂ attracted our attention due to its supreme properties such as suitable bandgap, high conductivity, high photo- and thermal-stability in photovoltaic devices. We investigated a series of <111> layered double-perovskites which can be derived from Cs₄CuSb₂Cl₁₂ through the elemental substitution. High-throughput first-principles calculations identified three stable layered double-perovskites Cs₄MnSb₂Cl₁₂, Cs₄CuSb₂Cl₁₂ and Cs₄ScSb₂Br₁₂. The ground state structure of Cs₄MnSb₂Cl₁₂ has the R-3m symmetry and exhibits antiferromagnetic(AFM) ordering, while the Cs₄CuSb₂Cl₁₂ and Cs₄ScSb₂Br₁₂ favor the C2/m symmetry and show AFM ordering. Our calculated results are consistent with the experimental observations, i.e., the ground state structures of Cs₄MnSb₂Cl₁₂ and Cs₄CuSb₂Cl₁₂ have R-3m and C2/m symmetry and they both exhibit AFM behavior, showing that our high-throughput calculation is valid for searching the thermodynamically stable <111> layered magnetic double-perovskites. A new layered double-perovskite Cs₄ScSb₂Br₁₂ is predicted for the first time and it may be synthesized experimentally in the future.