Chiral Ruthenium Halide Semiconductor with Strong Antiferromagnetic Coupling

Chiral hybrid organic-inorganic metal halides have attracted wide attention owing to their superior chiroptoelectronic and chirospintronic properties. Here, a new class of chiral lead-free metal halides, (R/S-MBA)3Ru2Br9 (MBA = methylbenzylammonium), with unique magnetic properties is reported. (R/S-MBA)3Ru2Br9 is composed of a surface-shared octahedron dimer separated by chiral cations and crystallizes into the Sohncke space group of P212121. The crystal structures, chiroptical, magnetic properties, and magnetic circular dichroism of (R/S-MBA)3Ru2Br9 are systematically investigated. Owing to the strong antiferromagnetic coupling between the Ru atom through bromine bridge in the [Ru2Br9]3- dimer and the weak ferromagnetic coupling between the neighboring [Ru2Br9]3- dimer, (R/S-MBA)3Ru2Br9 exhibits antiferromagnetic property with Neel temperature at 7 K. Considering the unique magnetic property of ruthenium, together with the rapid progress of antiferromagnetic spintronics and optospintronics recently, this work provides a novel multifunctional lead-free chiral magnetic candidate toward chiral optoelectronics and antiferromagnetic spintronics. A new type of chiral lead-free metal halide (R/S-MBA)3Ru2Br9 (MBA = methylbenzylammonium) is reportede, and the chirality of chiral cations is successfully transferred to the inorganic skeleton. These ruthenium-based chiral perovskites exhibit strong antiferromagnetic property, which is mainly due to the strong antiferromagnetic coupling between the adjacent Ru atom in the [Ru2Br9]3- dimer.image