Density functional theory (DFT) calculations demonstrate the correlation between the broad emission with the self-trapping of excitons inside the inorganic scaffold for the majority of 2D perovskites, while emission within the 0D perovskitoids (1,3-XDA)2PbCl6 origins from the organic spacers itself. Sharp band-to-band emission is only observable for the ( Single crystals of the four lead-chloride compounds with 1,3-PDA, 1,4-PDA, 1,3-XDA and 1,4-XDA have been grown (see Experimental Section in Supporting Information, SI) and characterized by single-crystal x-ray diffraction (chemical structures reports in Figure of Supporting Information, SI). The resulting crystal structures and chemical formulas are reported in Table . Note that 1,3-PDA and 1,4-PDA have been previously used in preparing chloride perovskites reporting only the crystal structure without any further characterization of optical or electronic properties. According to Table , the prepared compounds show different structure types, as depicted in Figure .