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Updated: Jul 13, 2025
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Published on: April 14, 2020
Symmetry and Rigidity for Boosting Erbium-Based Molecular Light-Upconversion in Solution
Soroush Naseri1, Inès Taarit1, Hélène Bolvin2
1Department of Inorganic and Analytical Chemistry, University of Geneva, 30 quai E. Ansermet, 1211, Geneva 4, Switzerland.
Abstract:
Previously limited to highly symmetrical homoleptic triple-helical complexes [Er(Lk)3 ]3+ , where Lk are polyaromatic tridentate ligands, single-center molecular-based upconversion using linear optics and exploiting the excited-state absorption mechanism (ESA) greatly benefits from the design of stable and low-symmetrical [LkEr(hfa)3 ] heteroleptic adducts (hfa- =hexafluoroacetylacetonate anion). Depending on (i) the extended π-electron delocalization, (ii) the flexibility and (iii) the heavy atom effect brought by the bound ligand Lk, the near-infrared (801 nm) to visible green (542 nm) upconversion quantum yield measured for [LkEr(hfa)3 ] in solution at room temperature can be boosted by up to three orders of magnitude.
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