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Updated: Sep 19, 2025
Author Spotlight: Magnetometric Characterization of Intermediates in the Solid-State Electrochemistry of Redox-Active Metal-Organic Frameworks
Published on: June 9, 2023
Elucidating the Correlation Between the Redox Potential, Spin State, and Crystal Structure in a Series of Ferrous
Livia Getzner1, Yasmine Remili1, Zakaria Ziani1
1LCC, CNRS and Université de Toulouse, UPS, INP, Toulouse, France.
Abstract:
Accurately predicting the spin crossover (SCO) temperature (T1/2) in spin crossover compounds remains a significant challenge due to their extreme sensitivity to minor variations in ligand and crystal structure. In this study, we uncover a critical link between the redox potential of ligands and SCO behavior within Hofmann-type clathrates {Fe(R-pbpy⁺)₂[μ₂-M(CN)₄]₂} (R = electron-donating or electron-withdrawing groups, M = Pd or Pt). Through precise tuning of the ligands' electronic properties, we establish a correlation between redox potential, space group, and SCO temperature, explained by an adaptation of Marcus theory of electron transfer. These findings not only provide a deeper understanding of the factors governing SCO behavior but also present a promising strategy for the rational design of SCO materials with tailored properties.
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