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{[Cu(II)(4,4'-bpy)(2)(H(2)O)][Cu(II)(2-pySO(3))(3)](NO(3))}·H(2)O, obtained serendipitously by the reaction of the constituents in water, consists of parallel coordinatively bonded cationic (4,4) corrugated square-grids polymer of {[Cu(II)(4,4'-bpy)(2)(H(2)O)](2+)}(n) threaded by π-π and H-bonded supramolecular chains of [Cu(II)(2-pySO(3))(3)](-) through the open squares. A single-crystal to single-crystal transformation takes place upon removal of the noncoordinated water by controlled heating. The resulting structure exhibits a rearrangement of the coordination of the copper atoms in the grids, where the Cu-H(2)O bond is elongated from 2.250(3) to 2.628(3) Å while the Cu-NO(3) is shortened from 3.122(3) to 2.796(1) Å. This process is reversible as demonstrated by the single crystal structure after rehydration with corresponding bond distances of 2.224(3) and 3.152(3) Å. Such a cooperative effect may be associated with the Jahn-Teller distortion of the copper(II) ion accompanying the shuttle action of the hydrogen-bonded water and nitrate moiety.

A new pillared-layer coordination polymer, [Co(3)(pybz)(2)(pico)(2)](n) (1; pybz = 4-(pyridin-4-yl)benzoate, pico = 3-hydroxypicolinate), contains rare 2D [Co(3)(pico)(2)](n)(2n+) layers formed by linear cobalt(II) trimers through the unusual mu(4)-kappaN,O:kappaO'-mu(2):kappaO''-mu(2) bridging mode of pico ligands, which are further cross-pillared by exotridentate bridging pybz ligands to form a three-dimensional structure with an unusual uninodal 8-connected body-centered-cubic topology. The bulk magnetic behavior of 1 exhibits ferrimagnetic long-range ordering below 2.6 K, which mainly arises from the cooperative magnetic effect of the intra- and intertrimer arrangements in the 2D magnetic system based on the nature of the exchange modes of mu(2)-hydroxyl, mu(2)-carboxylate oxygen, and 1,1,3-mu(3)-carboxylate bridges.

In the title compound, [Cd(C(10)H(16)O(4))(C(16)H(14)N(4))](n), the Cd(II) ion is six-coordinated in a distorted octa-hedral geometry by four carboxyl-ate O atoms from two sebacate ligands and two N atoms from the chelating 1,4-bis-(2-benzimidazol-yl)ethanebutane ligand. Neighboring Cd(II) ions are bridged by the sebacate ligands, forming a zigzag polymeric chain structure. The chains are further extended into a three-dimensional supra-molecular structure through inter-molecular N-H⋯O hydrogen bonds.

A highly stable pillared and double-walled zinc(II) metal-organic framework with regular nanochannels displays single-crystal to single-crystal transformation upon desolvation and a large quantity of iodine uptake, controlled release, and electrical conductivity elevation due to synergy between the iodine guests and the host framework.

The anionic CdI(2)-type topological net, [Cu(2)(tci)(2)](2-), and the pentanuclear copper cluster cation [Cu(5)(tci)(2)(OH)(2)(H(2)O)(8)](2+) [tci = tris(2-carboxyethyl)isocyanurate] form a complementary 3D supramolecular framework. Interestingly, there exist centrosymmetric cyclic (H(2)O)(18) clusters in the cavities.

The title complex, [Mn(N(3))(2)(C(9)H(10)N(2)O)(2)], possesses crystallographically imposed twofold symmetry. The Mn(II) atom is coordinated by four N atoms and two O atoms in a distorted octa-hedral geometry. The crystal packing is stabilized by strong inter-molecular O-H⋯N hydrogen bonds.

In the mononuclear title complex, [Co(NCS)(2)(C(9)H(10)N(2)O)(2)]·CH(3)OH, the cobalt(II) ion is surrounded by two (1-methyl-1H-benzimidazol-2-yl)methanol bidentate ligands and two thio-cyanate ligands, and exhibits a distorted octa-hedral coordination by four N atoms and two O atoms. The structure is consolidated by hydrogen bonds between the organic ligand, thio-cyanate anion and the uncoordinated methanol mol-ecule, leading to a chain along [100].

In the crystal structure of the title coordination polymer/co-crystal, {[ZnCl(2)(C(18)H(18)N(4))]·C(18)H(18)N(4)}(n), the tetrahedrally coordinated Zn(II) ions are linked by the N-heterocycle into a linear chain. Another N-heterocycle present is not coordinated to the metal atom but inter-acts with the chain through N-H⋯N and N-H⋯Cl hydrogen bonds. The butyl chain of the uncoordinated ligand is disordered over three positions in a 0.511 (4):0.289 (5):0.200 (5) ratio.

The title compound, [ZnCl(2)(C(16)H(14)N(4))], crystallizes with two mol-ecules in the asymmetric unit. The Zn(II) atoms show distorted tetrahedral coordination environments. Adjacent mol-ecules are linked by N-H⋯Cl hydrogen bonds, forming a three-dimensional network.

The dinuclear title compound, [Pb(2)(C(6)H(8)O(4))(NO(3))(2)(C(19)H(13)N(5))(2)], lies with the mid-point of the butyl chain of the bridging adipate unit on a center of inversion. The Pb(II) ion is covalently bonded to the nitrate anion and is bonded to a carboxyl-ate group of the adipate unit by another covalent bond. The N-heterocycle functions in a chelating tridentate mode. The metal atom exists in a Ψ-octa-hedral coordination environment. When weaker Pb⋯O inter-actions are also considered, the geometry is a Ψ-tricapped trigonal prism in which the lone-pair electrons occupy one face of the trigonal prism. Adjacent mol-ecules are linked into a layer structure by N-H⋯O hydrogen bonds.

The Ni(II) atom in the title compound, [Ni(C(12)H(8)NO(2))(2)(H(2)O)(4)], exists in an all-trans octa-hedral coordination environment. The 3-(4-pyrid-yl)benzoate ligand binds to Ni atom through the pyridyl N atom; the pyridine and benzene rings are oriented at a dihedral angle of 26.27 (10)°. Adjacent complexes are linked by O-H⋯O hydrogen bonds, forming a three-dimensional network. The metal atom lies on a special position of 2 site symmetry in the crystal structure.

The first structurally authenticated example of coordinated polymer featuring homometallic pillared-trilayer structure, [Co(3)(ina)(2)(pico)(2)(H(2)O)(2)](n) (1), was built from mixed pyridyl-type monocarboxylates, isonicotinate (ina) and 3-hydroxypicolinate (pico), containing Kagome-type [Co(3)(pico)(2)(H(2)O)(2)](n)(2n+) trilayers. The magnetic phase diagram of 1 shows a metamagnetic transition below 3.2 K, arising from the competing interactions between the antiferromagnetic intralayer couplings in different amplitudes with obviously noncompensated moments versus weak AF interlayer coupling.

The four-ring system in the title compound, C(16)H(9)NO(2)·CH(3)OH, is planar (r.m.s deviation = 0.03 Å); the methanol solvent mol-ecule forms a hydrogen bond to the quinoline N atom.

A 2D pillared bilayer coordination polymer, [Co(5-NH(2)-bdc)(bpy)(0.5)(H(2)O)] x 2 H(2)O (1; 5-NH(2)-bdc = 5-aminoisophthalate; bpy = 4,4'-bipyridine) has been hydrothermally synthesized and shows a novel microporous host framework with 1D channels and high thermal stability (approximately 400 degrees C). The framework of 1 exhibits reversible single-crystal-to-single-crystal transformations upon removing and rebinding the coordinated waters as well as replacing them with MeOH and EtOH from the solvent. X-ray crystallography reveals that the coordination geometry of Co(II) changes from octahedron to square pyramid, as well as the shrinkage/expansion of pore deformation in respect to the subsequent shear motion of bpy pillars and vice versa. The dehydrated form 2 exhibits a shape recognition ability, which can accommodate linear molecules, such as MeCN and 2-propynyl alcohol, and interesting storage capabilities for oversized MeOH, EtOH, and benzene molecules, concomitant with spongelike dynamic transformation. The microcalorimetric study indicates that the crystalline state-liquid guest exchange and guest inclusion processes (1 superset MeOH or EtOH, 2 superset MeOH, EtOH or MeCN) are feasibly endothermic reactions with the values of molar enthalpy, DeltaH(theta)(m), of +21.38(96), +12.68(85), +25.92(86), +17.03(57), and +14.93(75) kJ mol(-1), respectively.

Solvothermal treatment of a mixture of Co(OAc)(2), NaN(3), NaN(CN)(2), HF, MeCN, and H(2)O generated an AlB(2)-like metal-organic framework, namely, [{(Co(3)F)(3)(trta)(2)(H(2)O)(9)}{Co(Hbta)(3)}(2)].11H(2)O (1) (H(3)trta = N,N,N-tris-tetrazol-5-yl-amine; H(3)bta = N,N-bis-tetrazol-5-yl-amine), in which supertrianglar supramolecular building blocks (SBBs) {(Co(3)F)(3)(trta)(2)} act as 12-connected nodes of hexagonal prisms. The unprecedented ligand N,N,N-tris-tetrazol-5-yl-amine is in situ generated via metal-assisted reactions of NaN(CN)(2), MeCN, and NaN(3), and a possible mechanism involves both 1,3-dipolar cycloaddition and nucleophilic addition. The F-centered Co(3) triangles are bridged by trta groups to result in supertriangular {(Co(3)F)(3)(trta)(2)} SBBs that are further arranged in a frustrated triangular lattice. The long-range ordering temperature is reduced to 4.8 K due to strong spin frustration.

The Ni atom in the title compound, [Ni(C(8)H(8)NO(3))(2)], lies on a center of inversion in a square-planar coordination enviroment. The hydroxyl group of one anion forms a short hydrogen bond to the metal-coordinated O atom of the other anion.

A 1D rigid, linear coordination polymer, (4,4'-bipyridine)(2-pyridylsulfonate)copper, has been applied for the controlled-assembly of a new porous host that generates 1D channels by an interdigitated packing through the recognition of hydrogen bonding and pi-pi stacking interactions. The porous structure is architecturally robust when it reversibly uptakes water molecules and exchanges guest small molecules (MeOH, i-PrOH) from solution as determined by single-crystal-to-single-crystal transformation studies. Moreover, the open-channel solid displays irreversible benzene and toluene vapor sorption behaviors attributed to a widening of the channel cross-section that fetters the larger guest molecules, resulting from the dynamic, "soft" supramolecular framework.

A new 2D coordination polymer Co3(OH)2(pa)2(ina)2 (1, pa = 3-(1H-benzimidazol-2-yl) propanoic carboxylate, ina = isonicotinate) contained uncommon, linear Co(ii) trimers of mixed Td-Oh-Td geometries, exhibits spin canting below 20 K. Such magnetic behavior mainly arises from the Dzyaloshinski-Moriya interaction from the anisotropic, mixed geometries trimeric Co(II) ions to the crimpled 2D network based on the nature of the binding modes of Co(II)-carboxylate trimer and the effect of the intertrimers arrangement of 1. The mixed single-carboxylate-aromatic amine ligands bridged metal systems display a new structurally authenticated example of a thick 2D layer, and also indicate homometallic Co(II) clusters with Td-Oh-Td mixed-geometries can result in relatively obvious noncompensation moments, according to different efficient spins of Co(II) at very low temperature, in spite of antiferromagnetic intracluster interactions.

A manganese succinate having a layer structure in which the layers are pillared by the isonicotinate spacers in a 3D architecture exhibits long-range ferrimagnetic order below 5.0 K, with the ferrimagnetism arising, for topological reasons, from the nature of the carboxylate binding modes. The compound is the first structurally authenticated example of a 3D ferrimagnet, featuring a homometallic topological ferrimagnetic sheet among metal carboxylates.

A microporous 3D cobalt(II) coordination polymer featuring pillared layers [Co(2)(ma)(ina)](n) x 2nH(2)O (1 x 2H(2)O) (ma = malate, ina = isonicotinate) was generated by hydrothermal treatment with a void volume of 25.8%, in which the in-situ generated ma ligands connect the Co(II) ions into a 2D lattice with mixed and multiple exchange-bridges, affording a new geometrical topology different from the Kagomé lattice and leading to spin frustration. The rigid ina-pillared metallic-layered structure could retain 3D structural ordering upon guest removal and exchange. By soaking guest-free host in MeOH and methanamide (HCONH(2)) solutions, single crystals of dehydrated were transformed into single crystals of 1 x MeOH and 1 x HCONH(2), respectively, without apparent host-structural changes. 1 can also be rehydrated into 1 x 2H(2)O'. The guest-inclusion crystals have been characterized by X-ray single-crystal diffraction at 293 K and 93 K, confirming the single-crystal-to-single-crystal transformations and providing detailed information of the guest molecules confined in the subnanospace and host-guest and/or guest-guest hydrogen-bonding interactions. The magnetic behaviours of this family of porous magnetic materials are complex due to the influences of multiple metal sites, intra- and inter-layer exchanges, spin-orbit coupling, as well as geometrical frustration, which show magnetic ordering at <2 K, 3.5 K, 3.5 K, and 8 K for 1, 1 x MeOH, 1 x HCONH(2), and 1 x 2H(2)O, respectively, due to the different size of guest molecules along with the different host-guest interaction, which may slightly modify the path of magnetic exchange, decrease the intensity of the spin-frustration in the 2D lattice, and cooperatively enhance the magnetic ordering temperature.

The isostructural, chiral molecular magnetic materials with the formula [MxM'(2-x)(ca)2(1,4-dimb)]n [H2ca = D-(+)-camphoric acid, 1,4-dimb = 1,4-di-(1-imidazolyl-methyl)-benzene, M = Ni(II), M' = CoII, 0 < or = x < or = 2] consist of ca-bridged (4,4) layers with [M2(O2CR)4] as secondary building units that are pillared by the 1,4-dimb ligands into a unique 3D framework. The high-spin octahedral symmetry and the proportions of the mixed-metal ions were characterized by UV-vis spectroscopy. The compounds exhibit the onset of antiferromagnetic ordering at 7.5 approximately 23 K, as well as weak ferromagnetism, spin-flop, and glassy behavior that result from the randomness of the mixed-metal pairs, magnetic anisotropy of the metallic cations, and antisymmetric exchange. The composites should be regarded as molecular alloys of the pure Ni(II) and Co(II) compounds. The magnetic behavior of the solid solutions shows unambiguously that the organic bridges, bond angles, and bond distances greatly influence the effective interactions and bring about cooperative magnetic behavior in the chiral 3D frameworks.

The title compound, [Cd(C3H6NO5P)(H2O)2]n, is a three-dimensional polymeric complex. The asymmetric unit contains one Cd atom, one N-(phosphonomethyl)glycine zwitterion [(O-)2OPCH2NH2+CH2COO-] and two water molecules. The coordination geometry is a distorted CdO6 octahedron. Each N-(phosphonomethyl)glycine ligand bridges four adjacent water-coordinated Cd cations through three phosphonate O atoms and one carboxylate O atom, like a regular PO(4)3- group in zeolite-type frameworks. One-dimensional zigzag (-O-P-C-N-C-C-O-Cd-)n chains along the [101] direction are linked to one another via Cd-O-P bridges and form a three-dimensional network motif with three types of channel systems. The variety of O-H...O and N-H...O hydrogen bonds is likely to be responsible for stabilizing the three-dimensional network structure and preventing guest molecules from entering into the channels.

In the title compound, [Cd(C9H6O5)(C10H8N2)(H2O)]n, the CdII atom is coordinated in a distorted octahedral fashion by two carboxylate groups (one in a monodentate and one in a bidentate fashion) from two 4-carboxylatophenoxyacetate anions, two N atoms from a 2,2'-bipyridine ligand and one aqua ligand. The structure is a helix with a long pitch of 16.441 (5) A. A three-dimensional supramolecular network is further constructed through pi-pi stacking and hydrogen-bonding interactions between the helices.

Single crystals of a neutral, microporous, laminated metal-organic framework (MOF)[Fe(pydc)(4,4'-bipy)]xH(2)O (1xH(2)O)(H(2)pydc = 2,5-dicarboxypyridine, 4,4'-bipy = 4,4'-bipyridine) were generated by hydrothermal synthesis, and its crystal structure was determined. 1xH(2)O retains the framework robustness to ca. 370 degrees C and is insoluble in common organic solvents. By soaking in MeOH and EtOH solutions, 1xH(2)O was transformed directly from the parent single crystals into single crystals of 1xMeOH or 1xEtOH, respectively. Meanwhile, 1xH(2)O shrank to the guest-free framework (h) or (v), respectively, under appropriate heating (up to 160 degrees C in N(2)) or vacuum treatment (10 mmHg) at room temperature. Compared to that of 1xH(2)O, the unit-cell volume of 1xEtOH slightly increases by 2.9%, whereas those of (h) or (v) are reduced by 8.2 and 6.6%, respectively. The anhydrous (v) was found to be highly chemically reactive, taking up ethanol vapor to furnish the solvated crystal structure of an 'expanded' framework 1xEtOH. In a mixture of ethanol-DMF or ethanol-benzene, a selective exchange process was observed, with only ethanol molecules exchanged into the structure due to the limited free size of the channels in the framework of. All the transformed crystals have also been characterized by X-ray single-crystal diffraction to understand the crystal-to-crystal transformation, which have different free volumes (6.5-20.4%).