[Ga(C2H6OS)6](SbBr6): A Highly Luminescent Organic–Inorganic Hybrid Bimetallic Bromide Synthesized via a Cation Hybridization Strategy

In this report, a new organic-inorganic hybrid bimetallic halide with excellent luminescent properties, namely, [Ga(C2H6OS)6](SbBr6), has been synthesized and characterized. This compound crystallizes in the trigonal space group R3̅ with a = b = 13.83069(14) Å, c = 15.7632(3) Å, V = 2611.34(7) Å3, and Z = 3, and features a zero-dimensional structure composed of isolated [Ga(C2H6OS)6]3+ hybrid cation clusters and (SbBr6)3- inorganic anion octahedra. [Ga(C2H6OS)6](SbBr6) crystals exhibit bright yellowish-green photoluminescent broadband emission centered at 540 nm with a full width at half-maximum of 115 nm, a large Stokes shift of 175 nm, and a high photoluminescence quantum yield of 43.1%. Moreover, [Ga(C2H6OS)6](SbBr6) displays impressive radioluminescence performance when excited by X-rays, with a high light yield of 13 500 photons MeV-1 and excellent radiation resistance. Flexible films incorporating [Ga(C2H6OS)6](SbBr6) with polydimethylsiloxane illustrate the X-ray imaging ability with a high spatial resolution of approximately 10 lp mm-1 and a low detection limit of 161.2 nGyair s-1. These preliminary investigations demonstrate the considerable potential of [Ga(C2H6OS)6](SbBr6) for applications in X-ray radiography.