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Updated: Sep 17, 2025
Accessing Valuable Ligand Supports for Transition Metals: A Modified, Intermediate Scale Preparation of 1,2,3,4,5-Pentamethylcyclopentadiene
Published on: March 20, 2017
Strong Magnetic Coupling and Single-Molecule Magnet Behavior in Tetrazinyl Radical-Bridged Metallocenes
Neha Bajaj1, Niki Mavragani1, Alexandros A Kitos1
1Department of Chemistry and Biomolecular Sciences, University of Ottawa, 10 Marie Curie, Ottawa, Ontario, K1N 6N5, Canada.
None:
Exchange coupling is essential in defining the magnetic behavior of polymetallic lanthanide-based (LnIII) single-molecule magnets (SMMs), where, thanks to the unpaired electron(s), radical ligands show promise as magnetic bridges between the paramagnetic metal centers. Combining high-performance lanthanide metallocene [Cp*₂Ln]+ (Cp* = pentamethylcyclopentadienyl) units with the 3,6-bis(2-pyrimidyl)-1,2,4,5-tetrazine radical ligand (bmtz•-) yielded two new radical-bridged dinuclear lanthanide metallocenes, [(Cp*₂Ln)₂(bmtz•-)](BPh4)·Solvent (Ln = Gd (1), Solvent = THF; Dy (2), Solvent = toluene). The strong magnetic exchange coupling of JGd-rad = -12.6 cm-1 observed in 1, was probed via SQUID magnetometry as well as computational studies. This, combined with the highly anisotropic DyIII ions in 2, leads to zero-field SMM behavior and slow magnetic relaxation through thermally activated processes.
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