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Updated: Jun 2, 2026
Stable Aqueous Suspensions of Manganese Ferrite Clusters with Tunable Nanoscale Dimension and Composition
Published on: February 5, 2022
Manganese clusters derived from a 2,6-diacetylpyridine dioximato ligand: structure and magnetic study
Albert Escuer1, Beatriz Cordero, Mercé Font-Bardia
1Departament de Química Inorgànica and Institut de Nanociència i Nanotecnologia de la Universitat de Barcelona (IN²UB), Martí i Franqués 1-11, 08028 Barcelona, Spain. albert.escuer@qi.ub.es
Abstract:
Reactions of 2,6-diacetylpyridine dioxime (dapdoH₂) with Mn(NO₃)₂ or Mn(SO₃CF₃)₂ under a variety of conditions or co-ligands yield compounds with the formula [Mn₆O₂(OMe)₂(dapdo)₂(dapdoH)₄](X)₂ in which X = NO₃⁻ (1) or SO₃CF₃⁻ (2), [Mn₈O₂(dapdo)₆(NO₃)₂]·H₂O (3) and [Mn(dapdoH₂)(N₃)₂](n) (4). Compounds 1, 3 and 4 were structurally characterized and equivalent structures for 1 and 2 were inferred from spectroscopic and analytical results. Compounds 1 and 2 consist of hexanuclear Mn₂(II)Mn₄(III) complexes whereas 3 consists of an octanuclear Mn₆(II)Mn₂(III) cluster in which the manganese atoms exhibit a rare bicapped elongated octahedral topology. Compound 4 consists of a 1D system bridged by double end-on azido ligands. Variable temperature magnetic studies were performed between 2-300 K, confirming the ground state S = 5 for 1 and 2, S = 0 for 3 and ferromagnetic response for 4.
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