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Updated: Sep 26, 2026

Magnetometric Characterization of Intermediates in the Solid-State Electrochemistry of Redox-Active Metal-Organic Frameworks
Published on: June 9, 2023
Chemical control of magnetism: oxidation-induced ferromagnetic spin coupling in the chromium dimer evidenced by
Kensuke Tono1, Akira Terasaki, Toshiaki Ohta
1Department of Chemistry, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
Abstract:
The photoelectron spectrum of the dichromium oxide cluster anion, Cr2O-, and the analysis by the density-functional theory revealed that the spins of the two Cr atoms in Cr2O- are ferromagnetically coupled, and that its total spin magnetic moment is as large as 9 mu(B). This ferromagnetic spin coupling is induced by oxidation; the mixing of Cr 3d with O 2p orbitals plays an important role in a spin coupling between the localized electrons at the two Cr sites bridged by the O atom. The present finding is in marked contrast to the pure chromium dimer, which is known to be antiferromagnetic due to the strong sextuple Cr-Cr bond.
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