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A new 2D Mn(II) complex named as [Mn3(HL)2(H2O)6]n (I) (H4L = 3-(2,4-dicarboxyphenyl)-2,6-dicarboxypyridine) was synthesized and characterized by IR, elemental analysis, and single-crystal X-ray diffraction method (CIF file CCDC no. 1915189). The complex crystallizes in the monoclinic space group C2/c with Z = 4, a = 20.6597(11), b = 9.0949(5), c = 20.6041(12) Å, β = 110.056(6)°. The crystal consists of trinuclear Mn(II) ion clusters {Mn3} which are linked by four independent HL3– ligands and these trimeric units are connected into 2D structure by pentadentate HL3– ligand in alternate bis(bridging) and chelated coordination modes. Thermogravimetry, powder X-ray diffraction, and magnetic measurement experiments are also carried out to determinethe thermal stability, phase purity and magnetism. The results show that weak antiferromagnetic interactions occur between the Mn(II) centers within bridging trinuclear {Mn3} cluster. [ABSTRACT FROM AUTHOR]

A heteronuclear metal organic framework containing erbium(III) and cobalt(II) ion based on a rigid ligand of substituted imidazoledicarboxylic acid has been synthesized and characterized by single-crystal X-ray diffraction analysis (CIF file CCDC no. 1019455). It's formula is [ErCo(μ-HMimda)(μ-Mimda) · 4HO] · 2 nHO, (HMimda = 1- H-2-methyl-4,5-imidazole-dicarboxylic acid). The complex crystallizes in the monoclinic system. It possesses an extended grid-like porous structure constructed from corrugated shaped 2D layer. Direct current magnetic susceptibility measurements for indicated the depopulation of the Stark components at low temperature and possible very weak antiferromagnetic interactions within heteronuclear MOF. [ABSTRACT FROM AUTHOR]

A novel binuclear iron(III) Schiff base complex [Fe(NO-Salpn)(μ-OH)] · HO ( I) (NO-Salpn = 5-nitrosalicylaldehyde-1,3-propanediamine) has been obtained through one-pot refluxing and condensation. Complex I was established by single-crystal X-ray diffraction analysis (CIF file CCDC no. 1005239) and further characterized by elemental analysis, IR spectroscopy, electrochemical and magnetochemical measurements. Complex I consists of two pseudooctahedral high-spin iron(III) units doubly bridged by two hydroxyl groups. The inter hydrogen bonding interactions connect the adjacent binuclear units into one dimensional (1D) infinite chain, and these 1D chains are further propagated into the two dimensional (2D) supramolecular network by weak intermolecular interactions. Variable temperature magnetic measurements indicate the presence of strong antiferromagnetic interactions between the two adjacent iron(III) ions. [ABSTRACT FROM AUTHOR]

A new cadmium(II) complex [Cd(NO-Salen)] containing Schiff base ligand (NO-Salen = N-mono-5-nitro-salicylideneamino ethanato) has been prepared through facile condensation reaction of sub-stituted salicylaldehyde with ethylene-diamine and has been structurally characterized by elemental analysis, IR spectra and X-ray diffraction. It is formulated as CHCdNO crystallizes in the orthorhombic system, space group of Pccn. The ligand of 5-nitrosalicylaldehyde-ethylene-diamine exhibits unusual mono asymmetry tridentate mode. The Cd ion has a coordination number of six and assumes a distorted octahedral geometry. It exhibits an offset π-π stacking interaction between the substituted benzene ligands of adjacent mononuclear complexes. The neutral monomeric units of [Cd(NO-Salen)] are linked into a one-dimensional (1D) array via the intermolecular hydrogen bonds and π-π stacking interactions. The complex exhibits strong emission in visible region with the maximum wavelength of 428 nm, which is tentatively assigned to the π → π* intraligand fluorescence. [ABSTRACT FROM AUTHOR]

The reaction of 2,6-pyridinedicarboxylic acid (HPydc) and ammonium oxalate with neodymium(III) nitrate affords the one-dimensional (1D) neodymium coordination polymer formulated as {[Nd(Pydc)(μ-CO) · 6HO] · 2HO} ( I), and characterized by elemental analysis, IR spectroscopy, and X-ray single-crystal diffraction. The complex presents 1D stair-like chain array bridged through oxalate, and these 1D chains are further linked into 3D supramolecular architecture by extensive intra- and intermolecular hydrogen-bonding interactions. Preliminary magnetic studies reveal the presence of weak antiferromagnetic couplings with the two adjacent magnetic centers bridged through the pyridine dicarboxylate oxygen atom in the complex. [ABSTRACT FROM AUTHOR]