Eu DBM 3Phen europium tris dibenzoylmethanate phenanthroline is a luminescent complex that exhibits strong photoluminescence properties due to the presence of the europium Eu ion. The photochemical properties of this complex are mainly determined by the electronic transitions between the energy levels of the Eu ion and the ligands DBM and Phen .In solution, Eu DBM 3Phen exhibits strong red luminescence under UV light excitation. This is due to the efficient energy transfer from the excited state of the ligands to the emissive levels of the Eu ion. The photoluminescence properties of Eu DBM 3Phen can be characterized by its excitation and emission spectra, quantum yield, and luminescence lifetime.The presence of oxygen in the solution can affect the photoluminescence behavior of Eu DBM 3Phen. Oxygen is a well-known quencher of luminescence due to its triplet ground state, which can interact with the excited states of the luminescent species, leading to non-radiative deactivation and a decrease in luminescence intensity.In the case of Eu DBM 3Phen, the presence of oxygen can lead to a decrease in the luminescence intensity and quantum yield, as well as a shortening of the luminescence lifetime. This is because oxygen can interact with the excited states of the ligands and the Eu ion, promoting non-radiative deactivation pathways and reducing the efficiency of the energy transfer process.To minimize the quenching effect of oxygen on the photoluminescence of Eu DBM 3Phen, the complex can be studied in an oxygen-free environment or in a solid matrix, which can limit the diffusion of oxygen molecules and their interaction with the luminescent species.