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Updated: Apr 7, 2026
Hyperspectral Imaging as a Tool to Study Optical Anisotropy in Lanthanide-Based Molecular Single Crystals
Published on: April 14, 2020
Structural features and near infra-red (NIR) luminescence of isomeric Yb(III) bipyridyl-N,N'-dioxide coordination
Gail M Sequeira1, Wayne Y Tan, Evan G Moore
1School of Chemistry and Molecular Biosciences, The University of Queensland, Brisbane, QLD 4072, Australia. egmoore@uq.edu.au.
Abstract:
The synthesis and structural characterization of a series of lanthanide complexes formed from YbX3 salts (X = NO3(-) or CF3SO3(-)) and the isomeric 4,4'-bipyridine-N,N'-dioxide (4,4'-bpdo) or 3,3'-bipyridine-N,N'-dioxide (3,3'-bpdo) ligands has been undertaken by X-ray crystallography. Depending on the choice of anion, the complexes isolated with L = 4,4'-bpdo yield either an extended 1D linear chain {[Yb(L)(NO3)3(CH3OH)]}∞ or a coordination polymer network {[Yb(L)4](CF3SO3)3}∞ which are isostructural with previously reported compounds using other Ln(iii) metals. The isomeric 3,3'-bpdo ligand yields a similar extended 1D linear chain {[Yb(L)(NO3)3(CH3OH)]}∞ when NO3(-) is used as the anion. However, when substituted by the typically non-coordinating CF3SO3(-) anion, inner sphere coordination yields a coordination polymer {[Yb(L)3(CF3SO3)](CF3SO3)2}∞ with a (2(2)·4(8)·6(5)) network topology. In an effort to rationalize the observed difference in coordinating behavior, DFT calculations of the isomeric bipyridyl-N,N'-dioxide ligands have been undertaken, but revealed no significant differences in the charge distribution of the coordinating N-oxide groups. Lastly, sensitized Yb(iii) emission in the Near Infra-Red (NIR) region operating via the well-known antennae effect has been observed and compared for two of the coordination polymers.
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