abstract
The understanding of intramolecular energy transfer (IET) processes in photoluminescent Eu3+ chelates is of great importance in the design of new efficient emitting devices, sensors, optical thermometers, etc. Even though the theoretical models have been established, some considerations on the participation of the thermally populated excited state (7)F1 are necessary for experiments at room temperature. This work presents theoretical simulations of the transients related to the ligand and lanthanide excited states by employing two IET processes models, with and without the consideration of the (7)F1 thermal population at 298 K for the [Eu(tta)(3)(H2O)(2)] compound. The transients were obtained from a numerical method of the differential rate equations for each excited state, simulating a high-power density as in transient experiments. It is shown that all transients are considerably affected by the introduction of the (7)F1 state and the predicted curves, especially for the ligand S-1 state, can be experimentally measured. Therefore, the proposed model suggests that when considering energy transfer processes involving ligand and Eu3+ states, the thermal population of the (7)F1 state should be taken into account at room temperature.
keywords
CRYSTAL-FIELD PARAMETERS; SPECTROSCOPIC PROPERTIES; OVERLAP MODEL; LANTHANIDE; COMPLEXES; EU3+; EUROPIUM(III); EQUATIONS
subject category
Optics
authors
Blois, L; Neto, ANC; Malta, OL; Brito, HF
our authors
Albano Neto Carneiro Neto
Junior ResearcherProjects
Nanoparticles - based 2D thermal bioimaging technologies - NanoTBTech (NanoTBTech)
acknowledgements
The authors are grateful to the Brazilian funding agencies CNPq and FAPESP for financial support. L. Blois is thankful to FAPESP for the Ph.D. scholarship (Grant 2020/16795-6). H.F. Brito is grateful to CNPq for the research grant (306951/2018-5). A.N. Carneiro Neto is thankful for the financial support from the European Union's Horizon 2020 FET Open program under grant agreement (No. 801305) is also acknowledged. This work was developed within the scope of the project CICECO Aveiro Institute of Materials, UIDB/50011/2020 and UIDP/50011/2020, financed by Portuguese funds through the FCT/MEC and cofinanced by FEDER under the PT2020 Partnership Agreement.