The First Chiral Catalan Solid based on Molybdenum Halide with Efficient Circularly Polarized Luminescence in the Deep-red Region

Angew Chem Int Ed Engl. 2025 Jun 23:e202502029. doi: 10.1002/anie.202502029. Online ahead of print.

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, (R-MBA)2Mo6Cl14 and (S-MBA)2Mo6Cl14 tetrakis hexahedra, which adopt the unique Catalan solid structure. These tetrakis hexahedra exhibit 24 unique 3c-2e Mo-Mo-Cl bonding, which is scarcely reported. Most importantly, these (R-MBA)2Mo6Cl14 and (S-MBA)2Mo6Cl14 tetrakis hexahedra exhibit strong circularly polarized luminescence in the deep-red region, accompanied by a longer emission lifetime of 114.14 μs at room temperature. Additionally, these chiral molybdenum halide tetrakis hexahedra are optically stable for three 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 tetrakis hexahedra. Our study expands the family of lead-free chiral metal halides and develops a novel strategy to design the high-performance deep-red CPL emitter.

Keywords: chiral metal halide, Catalan solid, tetrakis hexahedra, deep-red emission, circularly polarized luminescence.