A novel heterospin one-dimensional (1-D) chain complex containing both Cu(Ⅱ) and nitroxide radical ligands, {[Cu(tcph)(H2O)4][Cu(tcph)(NIT3Py)2]·2H2O}n (1) (H2tcph = tetrachloro-phthalic acid, NIT3Py = 2-(3′-pyridyl)-4,4,5,5-tetramethyl-imidazoline-1-oxyl-3-oxide), has been synthesized and structurally characterized. The structure consists of neutral chains of copper(Ⅱ) ions bridged by tcph and coordinated alternatively by nitroxide radicals as spin branches and solvated water as co-ligand. The magnetic data were fitted using an approximate theoretical model based on population analysis to obtain the coupling parameter values of JCu2-Rad = 22.4 cm-1 and J′Cu1-Cu2 = -2.4 cm-1, indicating the intramolecular ferromagnetic interaction between Cu(Ⅱ) and NIT3Py and weak antiferromagnetic interaction between Cu1 and Cu2 linked by tcph.
MA Yue, CHEN XiaoPing, CAO Dong, YAN ShiPing & LIAO DaiZheng Department of Chemistry, Nankai University, Tianjin 300071, China
A new dinuclear copper（Ⅱ） complex, [Cu（L）（py）]2 1 （H2L = N-（2-hydroxybenzyl）- salicylaldimine, py = pyridine）, has been synthesized and characterized by elemental analysis, IR and UV spectra. 1 crystallizes in space group P2 1/n with a = 8.2106, b = 10.715, c = 17.864A, β = 99.365°, V = 1550.7A3, Z = 4, C19H16CuN2O2, Mr = 367.88, Dc = 1.576 g/cm3,μ（MoKα） = 1.422 mm-1, F（000） = 756, the final R = 0.0280 and wR = 0.0746. Complex 1 is a centrosymmetric dimer with two copper（H） centers, two py ligands and two L2- ligands. Each L2- ligand donates its azomethine nitrogen and one of the phenolate groups to one copper（Ⅱ） ion and shares the other phenolate group between the two copper（H） ions, affording a Cu2O2 plane. Each copper（Ⅱ） center has a slightly distorted square pyramidal geometry with a bridging phenolate group at the apex. Magnetic studies suggest the presence of a weak ferromagnetic interaction Via two phenoxo bridges. The magnetic susceptibility data （2-300 K） of complex 1 were analyzed by means of H = -2JS1S2 -DSz. The least-squares fitting of the data to the theoretical equation leads to J = 10.3 cm-1, g = 2.03, D = 0.67 cm-1 and R = ∑（Xobsd -Xcalcd）2/∑Xobsd2= 2.76 × 10^-3.
Two supramolecular complexes,[Ni(rac-L)]3[CrO4]2[ClO4]2-4H2O (1) and [meso-H2L]0.5[VO3]-0.16H2O (2) (L= 5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetra-decane),have been prepared in an aqueous solu-tion,and detected by elemental analysis,IR,TG,and single crystal X-ray diffraction analyses. Com-pound 1 shows a one-dimensional hexagonal prism formed by the hydrogen bonding interactions between the secondary amines of rac-L and CrO42-anion/water molecules. Compound 2 displays a three-dimensional structure constructed by the hydrogen bond linking the helical chains of [VO3]nn-to the secondary amines of meso-L to generate 1D hexagon-shaped channels,and the channels are oc-cupied by guest water molecules.
This paper reports two new coordination polymers formed by carboxylate-substituted benzoimidazole and formate ligands: [Mn(L)·(HCO2)] n (1) and [Co(L)·(HCO2)] n (2) (L = benzoimidazol-1-yl-acetate). Complexes 1 and 2 are isomorphous and adopt a new 3,6-connected three-nodal topology showing interesting magnetic properties: spin canted antiferromagnetism for MnII complex 1, but simple antiferromagnetic coupling for CoII complex 2.
HU BoWenZHAO JiongPengYANG QianZHANG XiaoFengBU XianHe
