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Strong magnetic exchange coupling in a tetraazanaphthalene radical-bridged dinuclear dysprosium complex enables magnetic memory with a coercive field of 1.373 T, more than twice that of any other organic radical-bridged single-molecule magnet (SMM). 

The first 1,4,5,8-tetraazanaphthalene radicals were isolated and analysed through crystallography, EPR spectroscopy, DFT computations. The radicals exhibit electrical conductivity at room temperature, placing them among elemental semiconductors. 

Unprecedented organometallic lanthanide chain compounds containing 4,4′-bipyridine bridges were isolated, and in-depth studiedviasingle-crystal X-ray diffraction, magnetometry, spectroscopy, DFT andab initiocomputations. 

Abstract Herein, the first report on the isolated and unambiguously proven benzene radical trianion is presented. This unprecedented radical oxidation state of benzene is stabilized through two trivalent rare earth (RE) metal cations each supported by a bis(guanidinate) scaffold. Specifically, the one‐electron chemical reduction of the neutral inverse‐sandwich yttrium complex [[{(Me₃Si)₂NC(NⁱPr)₂}₂Y]₂(μ–ƞ⁶:ƞ⁶–C₆H₆)]1, containing a benzene dianion, with potassium graphite (KC₈) in the presence of [2.2.2]‐cryptand yielded the title complex [K([2.2.2]‐cryptand)][[{(Me₃Si)₂NC(NⁱPr)₂}₂Y]₂(μ–ƞ⁶:ƞ⁶–C₆H₆^•)]2, featuring a benzene radical trianion. Analyses through single‐crystal X‐ray diffraction, EPR and UV–vis spectroscopy, elucidated its molecular structure and revealed strong [Y^III–(C₆H₆)^3–•–Y^III] metal–radical interactions. Although the Y centers remain in the +3 oxidation state, the spin density of the unpaired electron resides primarily on the benzene trianion moiety and extends toward the Y^IIIions. Density functional theory (DFT) calculations on2corroborate this assignment and further suggest weak aromaticity for the benzene radical trianion. 

Abstract Anionic ancillary ligands play a critical role in the construction of rare earth (RE) metal complexes due to the large influence on the stability of the molecule and engendering emergent electronic properties that are of interest in a plethora of applications. Supporting ligands comprising oxygen donor atoms are highly pursued in RE chemistry owing to the high oxophilicity innate to these ions. The scarcely employed bis(acyl)phosphide (BAP) ligands feature oxygen coordination sites and contain a phosphide backbone rendering it attractive for RE‐coordination chemistry. Here, we integrate bis(mesitoyl)phosphide (^mesBAP) as an ancillary ligand into RE^IIIchemistry to generate the first dinuclear trivalent RE complexes containing BAP ligands; [{^mesBAP}₂RE(THF)(μ‐Cl)]₂(RE=Y, (1), Gd (2), and Dy (3); THF=tetrahydrofuran). Each RE center is ligated to two monoanionic^mesBAP ligands, one THF molecule and one chloride ion. All three molecules were characterized through single‐crystal X‐ray diffraction,³¹P NMR, IR and UV‐Vis spectroscopy.³¹P,¹H and¹³C NMR on the diamagnetic yttrium congener1confirm asymmetric ligand coordination. DFT calculations conducted on2provided insight into the electronic structure. The magnetic properties of2and3were investigated via SQUID magnetometry. The Gd^IIIions exhibit weak antiferromagnetic coupling, corroborated by DFT results.