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Updated: Dec 14, 2025
Hyperspectral Imaging as a Tool to Study Optical Anisotropy in Lanthanide-Based Molecular Single Crystals
Published on: April 14, 2020
Stark Sublevel-Based Thermometry with Tb(III) and Dy(III) Complexes Cosensitized via the 2-Amidinopyridine Ligand
Alexandros A Kitos1, Diogo A Gálico1, Raúl Castañeda1
1Department of Chemistry and Biomolecular Sciences, University of Ottawa, 10 Marie Curie, Ottawa, Ontario K1N 6N5, Canada.
Abstract:
Amidine-based ligand frameworks were employed to isolate a series of mononuclear lanthanide complexes. The employed N-2-pyridylimidoyl-2-pyridylamidine (Py2ImAm) undergoes metal-assisted hydrolysis yielding the ligand 2-amidinopyridine (PyAm), which coordinates to the lanthanide ions affording [Ln(acac)3(PyAm)], where Ln = Eu(III) (1), Gd(III) (2), Tb(III) (3), Dy(III) (4) along with the Y(III) analogue (5). The Eu(III), Tb(III), and Dy(III) congeners exhibit characteristic emissions of red, green, and yellow light, respectively, with emission quantum yields of 3, 65, and 8%, respectively. Due to changes in the thermal population of the Stark sublevels, the Tb(III) and Dy(III) complexes can be used as efficient optical thermometers with maximum relative sensitivities of 1.57 and 2.03% K-1 for 3 and 4, respectively. These results demonstrate the viability of PyAm as an antenna for the sensitization of lanthanide ions.
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