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Updated: Apr 23, 2026
Author Spotlight: Magnetometric Characterization of Intermediates in the Solid-State Electrochemistry of Redox-Active Metal-Organic Frameworks
Published on: June 9, 2023
CW and TR EPR study of photomagnetic properties of heptanuclear Fe(II)-Fe(III) complex
Ekaterina Batueva1,2, Andrey Sukhanov1, Yuri Kandrashkin1
1Zavoisky Physical-Technical Institute, FRC Kazan Scientific Center, Russian Academy of Sciences, Sibirsky Tract, 10/7, 420029 Kazan, Russia.
Abstract:
The photomagnetic behavior of a mixed-valence heptanuclear complex [Fe(II)(CN)6{Fe(III)L}6](SCN)2, where L = dianion N,N'-bis(1-hydroxy-2-benzyliden)-1,7-diamino-4-azaheptane, has been investigated. The structure of the complex was optimized using density functional theory with the def2-SVP basis set and the Tao-Perdew-Staroverov-Scuseria functional. Continuous wave (CW) and time-resolved electron paramagnetic resonance (TR EPR) spectroscopy measurements at low temperatures (20-65 K) reveal a reversible, light-induced change in EPR signal intensity, indicating photoswitching between high-spin and low-spin states. The analysis of the CW and TR EPR spectroscopy results identified two types of effects related to sample magnetization: local sample heating by light and magnetization changes associated with photoinduced high-spin to low-spin transitions. These results demonstrate the potential of this complex as a photoswitchable magnetic material.
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