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A CoII coordination polymer built from a mixed azide and zwitterionic pyridinium ions and its temperature-dependent magnetic properties are described. We used the Markov chain Monte Carlo (MCMC) method to fit the data, and found the following results: (1) there are strong correlations between the model parameters; (2) the data at above 28 K are well fitted by the magnetism model.

Cu(II) polymers of Hbidc (1H-benzimidazole-5,6-dicarboxylate), namely [Cu2(Hbidc)2(H2O)4·3H2O] n (1) and [Cu(Hbidc)] n (2), were synthesized under hydrothermal conditions by variation of the reaction temperature and characterized by physico-chemical, spectroscopic and single-crystal X-ray diffraction studies. At temperatures from 100 to 170 °C, we only obtained the 2-D structure compounds 1 and 2, in which the bridging mode of the Hbidc ligand increases from μ 3 to μ 5 and the number of water ligands decreases to 0. Both compounds have 3-D supramolecular architectures extended by hydrogen bonding and π–π interactions between the adjacent layers. Magnetic studies revealed that compound 1 shows weak antiferromagnetic properties and compound 2 exhibits ferromagnetic coupling between the two Cu(II) ions in the dimeric units.

A one-dimensional chain compound was formed by copper (II) hexafluoroacetylacetonate (hfac) and nitroxide radical 2-(4-pyridyl)-4,4,5,5-tetramethyl-imidazoline-1-oxyl-oxide (NITpPy). The product was structurally characterized by single crystal X-ray diffraction. [Cu2(hfac)4NITpPy] n crystallizes in the monoclinic C2/c space group with a = 19.70(2), b = 16.834(19), c = 15.274(18) A, β = 119.073, V = 4427(9) A3, Z = 4, R = 0.0699 wR 2 (all data) = 0.1752. In the compound, two different Cu(hfac)2 units are bridged by NITpPy. The nitrogen atom of pyridine ring is coordinated with Cu(II) ion to afford a three-spin complex. Cu(II) ions of Cu(hfac)2 and the oxygen atoms of nitronyl nitroxide formed weak coordination bonds with the bond length 2.495(8) A. A one-dimensional chain compound [Cu2(hfac)4NITpPy]n was formed by copper (II) hexafluoroacetylacetonate (hfac) and nitroxide radical 2-(4-pyridyl)-4,4,5,5-tetramethyl-imidazoline-1-oxyl-oxide (NITpPy). In the compound, two different Cu(hfac)2 units are bridged by NITpPy forming a 1D zigzag chain with the weak coordination bond Cu–O bond length 2.495(8) A.

A metal-organic polymer [Ni3(μ3-O)(PDB)3]·H2O (1) (PDB = pyridine-3,5-dicarboxylate), with antiferromagnetic interactions between the adjacent Ni atoms, containing trinuclear μ3-oxo-bridged metal units Ni3(μ3-O) have been synthesized by hydrothermal reaction of the achiral building blocks pyridine-3,5-dicarboxylate (3,5-PDB) and Ni(NO3)2·4H2O. Compound 1 shows a high symmetry three-dimensional snowflake-shaped (3, 9)-connected topology structures in which μ3-oxo mixed-valence Ni3O(CO2)6 clusters act as nine-connected nodes and PDB ligands act as three-connected nodes.

The title compound, [Co(C7H5O2)2(C12H16N3O2)2(H2O)2], was obtained from a conventional solvent evaporation method. The complex molecule is centrosymmetric, so pairs of equivalent ligands lietransto each other in a slightly distorted octahedral CoN2O4geometry. The CoIIion is coordinated by the pyridine N atoms from NITpPy ligands [NITpPy is 4,4,5,5-tetramethyl-2-(pyridin-4-yl)imidazoline-1-oxyl 3-oxide), water O atoms and two monodentate benzoate O atoms. The complex molecules are connected by O—H...O hydrogen bonds between water molecules and benzoate ligands, forming chains parallel to [100]. π–π stacking interactions between the benzoate ligands with centroid–centroid distances of 3.752 (2) Å connect the chains into layers parallel to (10-1).

In the polymeric title complex, {[Mn(O(2)CC(6)H(4)-p-OH)(2)(C(10)H(8)N(2))]·C(10)H(8)N(2)·2H(2)O}(n), the Mn(II) atom is coordinated in a distorted octa-hedral geometry defined by four O atoms from three different carboxyl-ate ligands and two trans-N atoms from two 4,4'-bipyridine ligands. In the crystal structure, an extensive range of O-H⋯O and O-H⋯N hydrogen bonds link the complex and all non-coordinated mol-ecules into a three-dimensional network.

In the title compound, C11H10ClN3S, the dihedral angle between the benzene and pyrimidine rings is 3.99 (4)°. In the crystal, intermolecular N—H...N hydrogen bonds link the molecules into ribbons of R22(8) rings parallel to [100]. Weak C—H...S contacts connect adjacent ribbons into a two-dimensional undulating layer-like structure extending parallel to (110). The benzene and pyrimidine rings of adjacent molecules have the offset face-to-face π–π stacking interactions in a zigzag fashion along the c axis, with perpendicular ring distances of 3.463 and 3.639 Å, and a dihedral angle between the planes of 3.99