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Updated: Apr 30, 2026

Author Spotlight: Magnetometric Characterization of Intermediates in the Solid-State Electrochemistry of Redox-Active Metal-Organic Frameworks
Published on: June 9, 2023
Magnetic coupling between metal spins through the 7,7,8,8-tetracyanoquinodimethane (TCNQ) dianion
Mohamed R Saber1, Andrey V Prosvirin, Brendan F Abrahams
1Department of Chemistry, Texas A&M University, College Station, TX 77842-3012 (USA); Department of Chemistry, Fayoum University, Fayoum, 63514 (Egypt).
Abstract:
A family of magnetic metal-organic frameworks, (Ph3PMe)2[M2(TCNQ)3] {M=Fe(2+), Co(2+), Ni(2+) and Zn(2+)} have been prepared and structurally characterized. The honeycomb-like "layers" consist of M(II) ions doubly bridged with dinitrilomethane moieties of two 7,7,8,8-tetracyanoquinodimethane (TCNQ) dianions which are further connected through phenyl rings to form a 3D dianionic framework [M2TCNQ3](2-) with Ph3PMe(+) cations filling cavities that run along the c axis. Studies of the magnetic coupling through the TCNQ dianion in these structures revealed that it can promote long-range magnetic ordering despite the long coupling pathway.
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