Manganese incorporation for cesium zinc chloride crystals and the resultant structural, and optical characteristics

Here, we have successfully synthesized manganese (Mn) doped cesium zinc chloride (Cs 2 ZnCl 4 ) crystals for the first time by a simple solvothermal method, which alters the optical properties due to the structural transformation. When Mn 2+ feeding ratio x is lower than 0.4, tetrahedral structure of Cs 2 ZnCl 4 crystals is dominant with green emission of Mn 2+ doping, but both tetrahedral and octahedral structure show green–red emission when Mn 2+ feeding ratio exceeds 0.4. Combining experimental analysis and density functional theory (DFT) calculations, different energy transfer pathways and photoluminescence (PL) emission are revealed. When the host lattice crystal field surroundings of tetrahedral coordination, due to the incorporation of Mn 2+ , the exciton relaxes to 4 T 1 and then transitions to 6 A 1 . However, when the host lattice crystal field surroundings have a strong ligand field strength, the excitons are more advantageously confined to the octahedron. Our work provides deeper insights into the structural transformation of zero-dimensional all-inorganic metal halide due to the Mn 2+ incorporation from doping to substitution of B site.