Avecilla, FernandoSoro, Lohona KevinKnighton, Richard C.Thor, WaygenPrzybilla, FrédéricJeannin, OlivierEsteban-Gómez, DavidPlatas-Iglesias, CarlosCharbonnière, Loïc J.2024-09-052024-09-052023Soro, L. K., Knighton, R. C., Avecilla, F., Thor, W., Przybilla, F., Jeannin, O., Esteban-Gomez, D., Platas-Iglesias, C., & Charbonnière, L. J. (2023). Solution-State Cooperative Luminescence Upconversion in Molecular Ytterbium Dimers. Advanced Optical Materials, 11(11). https://doi.org/10.1002/ADOM.202202307http://hdl.handle.net/2183/38895[Abstract] Two homometallic ytterbium dimers are prepared and their solution-state photoluminescence and upconversion properties are investigated. Both complexes exhibit two-photon cooperative luminescence upconversion in the visible region (λem ≈ 510 nm) upon excitation into the near-infrared Yb 2F5/2 ← 2F7/2 absorption band at 980 nm. This miniaturization of the cooperative luminescence phenomenon down to just two Yb ions unequivocally proves the mechanistic origins of this process. Time-resolved measurements and excited-state modeling indicate the presence of a slow recombination of two singly excited ions Yb*Yb* into a virtual excited state, which ultimately gives rise to the observed emission at ≈510 nm.engCreative Commons Attribution License CC-BYhttp://creativecommons.org/licenses/by/3.0/es/Cooperative luminescenceLanthanidesPhotoluminescenceUpconversionjournal articleopen access10.1002/ADOM.202202307