DFT calculations were performed in Gaussian 16; on the Dutch national e-infrastructure with the support of SURF Cooperative (lisa.surfsara.nl). Avogadro and Gabetid were used for the molecular editing and the MOs visualization. Density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations were performed to investigate the ground-state and the excited-state properties of five representative AL(DIPY)3 complexes. Hybrid B3LYP functional was used and a LANL2DZ basis set to optimize the ground state (S0) geometry. The same methods were applied and TD-DFT calculations were performed to calculate the excited singlet (S1) and triplet (T1) states and visualize the respective molecular orbitals (MOs). The S1 ( 1 E00) and T1 ( 3 E00) energies, the difference between the first singlet excited and triplet energy state (ΔES-T) are shown in Table along with the energy difference between [HOMO -LUMO], [(HOMO-1) -LUMO], [(HOMO-1) -(LUMO+1)] and [HOMO -(LUMO+1)].