First Chiral Catalan Solid Based on Molybdenum Halide with Efficient Circularly Polarized Luminescence in the Deep‐Red Region

Abstract The design of novel chiral metal halides with exceptional chiroptical properties has attracted significant research attention due to their potential applications in chiral optoelectronics and spintronics. However, developing the deep‐red circularly polarized luminescence (CPL) emitters is still challenging. In this work, we presented the first chiral molybdenum halide clusters by incorporating chiral methylbenzylammonium ( R / S ‐MBA) for the design of ( R ‐MBA) 2 Mo 6 Cl 14 and ( S ‐MBA) 2 Mo 6 Cl 14 tetrakis hexahedra, which adopt the unique Catalan solid structure. These chiral tetrakis hexahedra exhibit 24 unique 3 c ‐2 e Mo─Mo─Cl bonds, which are scarcely reported. Notably, these ( R ‐MBA) 2 Mo 6 Cl 14 and ( S ‐MBA) 2 Mo 6 Cl 14 tetrakis hexahedra demonstrated pronounced circularly polarized luminescence in the deep‐red region, accompanied by an extended emission lifetime of 114.14 µs at room temperature. Additionally, these chiral molybdenum halide tetrakis hexahedra are optically stable for 3 months. The four‐state spin sublevel model was employed to investigate the emission mechanism and found that the temperature‐dependent exciton dynamics lead to the dual‐band emission of the designed chiral tetrakis hexahedra. Our study expands the family of lead‐free chiral metal halides and develops a novel strategy to design a high‐performance deep‐red CPL emitter.