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Updated: Apr 20, 2026
Author Spotlight: Magnetometric Characterization of Intermediates in the Solid-State Electrochemistry of Redox-Active Metal-Organic Frameworks
Published on: June 9, 2023
Photomagnetic response in highly conductive iron(II) spin-crossover complexes with TCNQ radicals
Hoa Phan1, Shermane M Benjamin, Eden Steven
1Department of Chemistry & Biochemistry, Florida State University, 95 Chieftan Way, Tallahassee, FL 32306 (USA) http://www.chem.fsu.edu/∼shatruk/
Abstract:
Co-crystallization of a cationic Fe(II) complex with a partially charged TCNQ(.δ-) (7,7',8,8'-tetracyanoquinodimethane) radical anion has afforded molecular materials that behave as narrow band-gap semiconductors, [Fe(tpma)(xbim)](X)(TCNQ)(1.5)⋅DMF (X=ClO4(-) or BF4(-); tpma=tris(2-pyridylmethyl)amine, xbim=1,1'-(α,α'-o-xylyl)-2,2'-bisimidazole). Remarkably, these complexes also exhibit temperature-and light-driven spin crossover at the Fe(II) center, and are thus the first structurally defined magnetically bistable semiconductors assembled with the TCNQ(.δ-) radical anion. Transport measurements reveal the conductivity of 0.2 S cm(-1) at 300 K, with the low activation energy of 0.11 eV.
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