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Updated: Sep 15, 2025
Hyperspectral Imaging as a Tool to Study Optical Anisotropy in Lanthanide-Based Molecular Single Crystals
Published on: April 14, 2020
Exchange Bias in a Dinuclear Erbium Single-Molecule Magnet Bridged by a Helicene Ligand
Gabriela Handzlik1, Mikołaj Żychowicz1, Katarzyna Rzepka1
1Faculty of Chemistry, Jagiellonian University, Gronostajowa 2, 30-387 Kraków, Poland.
Abstract:
We report the synthesis and magneto-structural characterization of a dimeric Er-based single-molecule magnet (Er2) containing two [6]helicene-1,2-diol dianions as bridging ligands. Diamagnetic dilution with yttrium cations at the synthesis stage leads to a composition that can be approximated as ErY@Y2. This enables a direct comparison of the slow magnetic relaxation of these closely related single-molecule magnets (SMMs): dimeric Er2 with erbium-erbium magnetic interactions and ErY@Y2 where these interactions are absent and yet the coordination sphere of the lanthanide remains identical to that in the dimer. The antiferromagnetic Er-Er interactions in Er2 result in exchange bias accelerating the magnetic relaxation around the crossing magnetic field, while their absence in ErY@Y2 enables longer relaxation times and leads to a less complex magnetic behavior.
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