3 nm-wide Cyanometallate Fe-Co Tape Exhibiting Single-Chain Magnet Behavior.

Treatment of Co(OTf)2 ·6H2 O, Li[(pzTp)FeIII (CN)3 ], and H3 PMo12 O40 · n H2 O in protic solvents afforded two structurally related Fe-Co cyanometallate complexes: [{(pzTp)Fe(CN)3 }3 Co3 (MeOH)10 ][PMo12 O40 ]·H2 O·11MeOH ( 1 , pzTp- = tetra(pyrazolyl)borate) and {[(pzTp)Fe(CN)3 ]4 Co3 (MeOH)5 (H2 O)3 } n [HPMo12 O40 ] n ·3 n MeOH·6.5 n H2 O ( 2 ). Complex 1 consists of a cyanide-bridged hexanuclear [Fe3 Co3 ] cage, characterized by the fused conjunction of two mutually perpendicular trigonal bipyramids (TBPs, [Fe2 Co3 ] and [Co2 Fe3 ]), while complex 2 showcases an intricate cyanide-bridged Fe-Co tape comprising a central chain backbone of vertex-sharing [Fe2 Co3 ] TBPs alongside peripheral [Fe2 Co2 ] squares. Complex 2 is among the widest one-dimensional coordination assemblies characterized by the single-crystal X-ray diffraction technique. Magnetic studies revealed that complex 2 behaved as a single chain magnet with an effective energy barrier ( U eff / k B ) of 46.8 K. Our findings highlight the possibilities in the development of cyanometallate-POM hybrid materials with captivating magnetic properties.