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Updated: Aug 24, 2026
Magnetometric Characterization of Intermediates in the Solid-State Electrochemistry of Redox-Active Metal-Organic Frameworks
Published on: June 9, 2023
Exchange coupling of paramagnetic ions in a polyoxometalate matrix: density functional study of diiron(III)
Ekaterina M Zueva1, Henry Chermette, Serguei A Borshch
1Laboratoire de Chimie, UMR 5182 CNRS--Ecole Normale Supérieure de Lyon, 46 allée d'Italie, 69364 Lyon 07, France.
Abstract:
The quantum chemical (density functional) analysis of the antiferromagnetic interactions between the two iron centers incorporated into the gamma-silicotungstate is performed. The influence of the polyoxometalate framework on the exchange coupling within the diiron core unit is studied. The dependence of the strength of antiferromagnetic exchange on the protonation of the core bridges is considered. It is shown that the magnetic coupling is very sensitive to the distortions in core geometry. Variations in the core structure induced by the environment (such as the polyoxometalate framework) change the significance of superexchange pathways and give rise to new superexchange mechanisms. This effect is especially pronounced in the case of the hydroxo-bridged diiron core.
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