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Updated: Apr 25, 2026
Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Persistent compensated ferrimagnetism in the molecular framework Cr(pyrazine)3
Frédéric Aribot1, Maja A Dunstan1, Nathan J Yutronkie2
1Department of Chemistry, Technical University of Denmark, Lyngby, Denmark.
Abstract:
Molecular frameworks with ReO3- or perovskite-related topologies have been widely investigated for their structural versatility, yet examples displaying strong electronic and magnetic correlations have not been realized in such systems. Here we report the synthesis of Cr(pyrazine)3, a three-dimensional molecular framework adopting a cubic ReO3-type structure, in which Cr3+ ions are bridged exclusively by pyrazine radical anions. In Cr(pyrazine)3, antiferromagnetic coupling between the Cr3+ and radical sublattices, comparable in magnitude to that found in transition-metal oxides, leads to a nearly perfectly compensated ferrimagnetic ground state with an exceptionally small net magnetic moment. Owing to the symmetry and stoichiometry of the bipartite lattice, magnetic compensation persists over an extended temperature range rather than occurring only at a specific compensation temperature. Long-range magnetic order is observed well above room temperature, placing Cr(pyrazine)3 among the very few materials featuring robust compensated ferrimagnetism under ambient conditions.
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