Synthesis and soft crystal structure-induced broad emission of (NHCHNH)InBr·2HO.

We report a simple synthesis of a new lead-free zero-dimensional (0D) hybrid halide compound, (5P1)InBr·2HO [(5P1) = NHCHNH], which hosts isolated and distorted octahedra of [InBr(HO)], surrounded by bulky asymmetric organic cations [(5P1)] and HO molecules. The hybrid crystals exhibit broad self trapped excitonic (STE) emission due to strong anharmonic soft structure.