Novel, one bay-substituted perylene bisanhydride (6) and two bay-substituted perylene bisimides (7, 10) have been successfully synthesized with a large and swallow tail type, 2-decyl-1-tetradecanoyl substituents at the bay area (1 and 7 positions). The non-bay-substituted perylene bisimides with the same N-substituents were prepared as model compounds (3, 9) for comparison. Absorption and fluorescence, electrochemical, spectro-electrochemical, morphological properties of the compounds were investigated, and then, density functional theory (DFT) simulations were conducted. The compounds 6, 7 and 10 have shown J-aggregated featureless, very broad absorbance through the UV-vis-NIR region with a strong fluorescence quenching attributed to efficient intramolecular electron transfer from electron donor 2-decyl-1-tetradecanoyl substituent to PDI acceptor and scaffolds allow pi-pi intermolecular interactions, induced molecular aggregation. The absolute positions of LUMO and HOMO values for 3, 9, 6, 7 and 10 in solutions were - 3.91/ - 6.09 eV, - 3.93/ - 6.08 eV, -4.02/ - 5.90 eV, - 4.02/- 5.91 eV and - 4.02/ - 5.97 eV, respectively. The onset reduction potential of compounds 6, 7 and 10 are lower than those of compounds 3 and 9. Similarly, the onset oxidation potential values of the compounds 6, 7 and 10 are smaller than those of the non-bay-substituted perylene dyes 3 and 9. The synthesized compounds (3 with 7; 9 with 10) can be exploited as an off-on fluorescence probes for photonic applications.