Most polymetallic hybrid metal halides are assumed to show a homogenous distribution of the metal ions in the bulk. Herein, we demonstrate a core-shell model for the hybrid lead halide [(C6H18N3)2·Pb2Br10] (C6H18N3 = 2-(piperazin-1-yl)ethan-1-aminium) coated with a manganese bromide layer. This model can explain the different photoemission of this composite material, and provides new insights on the investigation of polymetallic low-dimensional organic metal halides.