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With the use of the tailored cyanometalate precursor, (Bu4N)[(Tp)Fe(CN)3] (Tp = Tris(pyrazolyl)hydroborate) as the building block to react with fully solvated CuII, CoII, and NiII cations, four one-dimensional (1D) heterobimetallic cyano-bridged chain complexes of squares, [(Tp)2FeII2(CN)6Cu(CH3OH)·2CH3OH]n (1), [(Tp)2FeII2(CN)6Cu(DMF)·DMF]n (2), [(Tp)2FeIII2(CN)6M(CH3OH)2·2CH3OH]n (M = Co (3) and Ni (4)), have been prepared. In complexes 1 and 2, the CuII ions are pentacoordinated in the form of a slightly distorted square-based pyramid, and they are linked by distorted octahedrons of [(Tp)Fe(CN)3]- to form 1D chains of squares. In complexes 3 and 4, both the central CoII and NiII ions have a slightly distorted octahedral coordination geometry, and they are bridged by [(Tp)Fe(CN)3]- to form similar 1D chains of squares. There are weak interchain π-π stacking interactions through the pyrazolyl groups of the Tp ligands for complexes 3 and 4. The crystal structures and magnetic studies demonstrate that complexes 1 and 2 exhibit intrachain ferromagnetic coupling and single-chain magnets behavior, and the blocking temperature is ca. 6 K for complex 1 and ca. 3 K for complex 2. Complexes 3 and 4 show significant metamagnetic behavior, where the cyanides mediate the intrachain ferromagnetic coupling between FeIII and CoII or NiII ions and the interchain π-π stacking interactions lead to antiferromagnetic couplings. The field dependence of the magnetization measurements shows that the critical field is around 1 kOe for complex 3 and 0.8 kOe for complex 4 at 1.8 K. [ABSTRACT FROM AUTHOR]

Two new cyano-bridged one-dimensional heterobimetallic coordination polymers, [(bpca)2FeIII2(CN)6Cu(H2O)2·1.5H2O]n (2) and [(bpca)FeIII(CN)3Cu(bpca)(H2O)·H2O]n (3), and a trinuclear complex, [(bpca)2FeIII2(CN)6Mn(CH3OH)2(H2O)2]·2H2O (4), have been synthesized using the tailored tricyanometalate precursor (Bu4N)[Fe(bpca)(CN)3]·H2O (1) (Bu4N+ = tetrabutylammonium cation; bpca = bis(2-pyridylcarbonyl)amidate anion) as a building block and structurally characterized. In complex 2, the CuII ions are six-coordinated in an elongated distorted octahedral environment, and they are linked by distorted octahedrons of [Fe(bpca)(CN)3]- to form 1D chain of squares. Complex 3 is an unexpected chiral heterobimetallic helical chain complex, in which the helical chain consists of the asymmetric unit of [(bpca)Fe(CN)3Cu(bpca)(H2O)]. In complex 4, there are two independent trinuclear clusters in one asymmetric unit, and the coordination modes of the two methanol and two water molecules coordinating to the central Mn(II) ion are different (cis and trans). Complex 2 shows metamagnetic behavior with a Neel temperature of TN = 2.2 K and a critical field of 250 Oe at 1.8 K, where the cyanides mediate the intrachain ferromagnetic coupling between the CuII and FeIII ions. Complex 3 shows ferromagnetic coupling between CuII and FeIII ions, the best-fit for χMT versus T using a 1D alternating chain model leads to the parameters J1 = 7.9(3) cm-1, J2 = 1.03(2) cm-1, and g = 2.196(3). Complex 4 exhibits ferrimagnetic behavior caused by the noncompensation of the local interacting spins (SMn = 5/2 and SFe = 1/2) which interact antiferromagnetically through bridging cyano groups. [ABSTRACT FROM AUTHOR]

A neutral nickel complex with the extended tetrathiafulvalene-4,5-dithiolate ligand benzotetrathiafulvalenedithiolate (btdt2-) is synthesized and characterized. From the structural analysis, the neighboring molecules in this complex are stacked in a different way compared to the previously reported single-component metal [Ni(tmdt)2]. The computational studies confirm that the difference in molecular packing results in the variance of conductivity. [ABSTRACT FROM AUTHOR]