A series of new lanthanide-radical complexes [{Ln(hfac)3}2(NITPhIM)2] (Ln = Nd (1), Eu (2), Tb (3), Er (4); hfac = hexafluoroacetylacetonate; NITPhIM = 2-[4-(1-imidazole)phenyl]-4,4,5,5- tetramethylimidazoline-1- oxyl...
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A series of new lanthanide-radical complexes [{Ln(hfac)3}2(NITPhIM)2] (Ln = Nd (1), Eu (2), Tb (3), Er (4); hfac = hexafluoroacetylacetonate; NITPhIM = 2-[4-(1-imidazole)phenyl]-4,4,5,5- tetramethylimidazoline-1- oxyl-3- oxide) have been prepared and characterized. Single crystal x-ray diffraction analyses reveal that these complexes are isostructural with one-dimensional chain structures. These consist in Ln(hfac)3 units bridged by the paramagnetic ligands by the means of coordination of their nitronyl nitroxide groups and imidazole rings. Interestingly, each Ln ion is either bound to two nitronyl nitroxide groups or to two imidazole units, and the different Ln centers alternate along the chain. Magnetic studies show that complex 3 exhibits a single-chain magnet behavior.
Three new cyanido-bridged heterometallic ReIVNiⅡand ReIVCuⅡone-dimensional systems were synthesized and extensively characterized both structurally and magnetically. Single-crystal x-ray diffraction analysis reveale...
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Three new cyanido-bridged heterometallic ReIVNiⅡand ReIVCuⅡone-dimensional systems were synthesized and extensively characterized both structurally and magnetically. Single-crystal x-ray diffraction analysis revealed that these compounds display a common topology, with chains composed of alternating [ReIVCl4(CN)2]2- and [MⅡ(cyclam)]2+(M = Ni in 1, Cu in 2) or [CuⅡ(N,N′-dimethylcyclam)]2+(in 3) building units. Two different chain orientations with a tilt angle of ca. 51° to 55° are present in the crystal packing of these compounds. The magnetic susceptibility measurements suggest the presence of intrachain ferromagnetic interactions between the S = 3/2 ReIVcenters and the 3d metal ions: S = 1 NiⅡor S = 1/2 CuⅡ. At low temperature, a three-dimensional ordered magnetic phase induced by interchain antiferromagnetic interactions (antiferromagnetic for 1 and 2; canted antiferromagnetic for 3) is detected for the three compounds.
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