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The asymmetric unit of the title compound, [Fe(C(12)H(6)O(4))(C(10)H(8)N(2))], consists of two independent Fe(II) atoms, two naphthalene-1,4-dicarboxyl-ate anions and two 4,4'-bipyridine ligands. The Fe(II) atoms are each coordinated by four O atoms of the naphthalene-1,4-dicarboxyl-ate anions and two N atoms of the 4,4'-bipyridine ligands within a distorted octa-hedron. Two Fe(II) atoms are bridged via the carboxyl-ate groups of two symmetry-related anions into dimers, which are further connected into chains. These chains are linked by additional anions into layers that are finally connected by the 4,4'-bipyridine ligands into a three-dimensional coordination network.

The variable coordination pattern of a hemilabile phosphazene ligand equipped with six pendent olefin groups facilitates the in situ recrystallisation of a silver(I) complex from an amorphous precipitate into a 1D coordination polymer and its subsequent isomerisation to a 3D coordination network.

The Cu2(3-iodobenzoate)4 paddlewheel has been investigated as a secondary building unit (SBU I) in the design and synthesis of a linear coordination network. The SBU was found to form halogen-bonded networks rather than coordination networks with simple short linkers such as 1,4-dioxane and diazabicyclo(2.2.2)octane (dabco). Increasing the linker size to 4,4′-bipyridine (bipy) resulted in a linear network containing both the paddlewheel SBU I and a new mononuclear SBU II. Further increase of linker size to 4,4′-bipyridylethane (bpe) results in two crystalline phases. The first consists of linear chains of SBU II and the second contains two types of network chain in one single crystal, single chains of SBU II along with double chains of a new dinuclear SBU III.

[Zn4(PdCl2)2(pydc)4(H2O)4(THF)6]·3.25THF (H2pydc = 3,5-pyridinedicarboxylic acid) was formed from the reaction between Zn(NO3)2·6 H2O and trans-[PdCl2(pydc)2] in THF, and was shown by X-ray crystallography to have a three-dimensional network structure in which {PdCl2(pydc)2}4− metalloligands are linked by Zn2 centres to form a mixed-metal coordination network.

The title compound, [Ho(2)(C(4)H(4)O(4))(C(8)H(4)O(4))(2)](n), was synthesized hydro-thermally. The Ho atom is coordinated by four O atoms from four benzene-1,4-dicarboxyl-ate (BDC) anions and four O atoms from three succinate anions, in a distorted square-anti-prismatic coordination geometry. The anti-prisms are bridged by the benzene-1,4-dicarboxyl-ate and succinate anions, into a three-dimensional coordination network. The succinate anions are located on centres of inversion.

The title compound, [Na2Co(C7H3NO4)2]n, is isostructural with the nickel(II) analog. In the crystal structure, the Co cation is coordinated by two N atoms and four O atoms of two pyridine-2,6-dicarboxylate groups with a strongly distorted octahedral geometry. The Na cations are coordinated by six O atoms of pyridine-2,6-dicarboxylate anions in an irregular geometry. The bis(pyridine-2,6-dicarboxylato)cobalt com­plexes are connected by the sodium cations into a three-dimensional coordination network.

The title compound, (Et3NH)2[MnCl4], was obtained unexpectedly in an attempt to prepare a carboxyl­ate-bridged coordination network. It is the first reported structure of a tertiary ammonium salt of the tetra­hedral [MnCl4]2− anion (Table 1). Each of the two crystallographically independent cations forms an N—H⋯Cl hydrogen bond to the anion (Table 2), generating discrete ion triples. The Mn—Cl bonds involving the hydrogen-bonded Cl atoms are longer than the others.

The tetrafunctional silane Si(C6H4CN-p)4 forms a coordination network with TiCl4 consisting of 4,2-connected layers containing large (56 atom) rings.

Using the O-alkylation of the lower rim of the calix[4]arene to impose the 1,3-alternate conformation and the functionalisation of the upper rim to set-up four nitrile groups pointing in a divergent fashion, an exo-ligand capable of forming linear coordination networks was obtained; upon self-assembly of the latter and silver cation, a linear coordination polymer was obtained and structurally analysed in the solid state by an X-ray study.

Crystallization of 3-cyanophenyl 4-cyanobenzoate 1 with AgSbF6 yields the non-centrosymmetric, fourfold interpenetrated grid structure [Ag(1)2]SbF6 2 through the crisscrossing of two-dimensional sheets.

Novel complexes of a cyclic amide with lanthanide metal cations form 2-D coordination networks; different metal cations give different chiral properties in the crystal structure.

Upon combining the organic tecton based on the [1,1,1,1]metacyclophane bearing four pyridine groups with silver cation, a tubular coordination network formed by double bridging of consecutive macrocycles by metal centres is obtained and structurally characterised in the solid state by an X-ray diffraction method. The same tecton when combined with HgCl2 leads to the formation of a doubly interpenetrated 2-D coordination framework.

Salamanders of the genus Ambystoma are a unique model organism system because they enable natural history and biomedical research in the laboratory or field. We developed Sal-Site to integrate new and existing ambystomatid salamander research resources in support of this model system. Sal-Site hosts six important resources: 1) Salamander Genome Project: an information-based web-site describing progress in genome resource development, 2) Ambystoma EST Database: a database of manually edited and analyzed contigs assembled from ESTs that were collected from A. tigrinum tigrinum and A. mexicanum, 3) Ambystoma Gene Collection: a database containing full-length protein-coding sequences, 4) Ambystoma Map and Marker Collection: an image and database resource that shows the location of mapped markers on linkage groups, provides information about markers, and provides integrating links to Ambystoma EST Database and Ambystoma Gene Collection databases, 5) Ambystoma Genetic Stock Center: a website and collection of databases that describe an NSF funded salamander rearing facility that generates and distributes biological materials to researchers and educators throughout the world, and 6) Ambystoma Research Coordination Network: a web-site detailing current research projects and activities involving an international group of researchers. Sal-Site is accessible at http://www.ambystoma.org.

A self-complementary tecton based on a zinc porphyrin core bearing two pyridines at the opposite meso positions leads to the formation of a 3-D coordination network in the crystalline phase which offers channels which are filled with solvent molecules; reversible exchange of the guest molecules has been proven to take place in a single-crystal-to-single-crystal type transformation demonstrating the robustness of the coordination framework.

Three Gd(III)-sulfate polymers [Gd(PNO)(H2O)2(SO4)]n (1), [Gd(NNO)(H2O)2(SO4)]n (2), and [Gd(INO)(H2O)(SO4)]n (3) exhibiting a systematic variation in framework dimensionality have been hydrothermally synthesized by using three isomeric pyridine carboxylate N-oxides, PNO = picolinate N-oxide, NNO = nicotinate N-oxide, and INO = isonicotinate N-oxide, as organic components. Compound 1 comprises 1D coordination chains that are unable to propagate to higher dimensionalities due to the convergent endo PNO ligand. The structure of compound 2 consists of hydrogen-bonded layers. The formation of the 2D layer is attributed to the more divergent NNO than PNO. Compound 3 consists of a 2-fold interpenetrating “3D herringbone” framework, in which the most divergent exo ligands of INO connect the individual Gd-sulfate inorganic chains to produce the 3D coordination network. It is demonstrated that the convergence or divergence of the three isomeric ligands of the pyridine carboxylate N-oxide can be used to engineer the dimensionality of the coordination polymers.

The reaction of corresponding cadmium salts with the flexible ligand 1,4-bis(1,2,4-triazol-1-ylmethyl)benzene (bbtz) affords the 3D coordination network [Cd3(bbtz)6(H2O)6](BF4)(6.1.75H2O (1), containing ribbons of rings and planar 2D (4,4) networks polycatenated with each other, the undulating 2D (4,4) network [Cd(bbtz)2(H2O)2](ClO4)2.2H2O (2), and ribbons of rings [Cd(bbtz)2(H2O)2](BF4)2.3DMF (3) and [Cd(bbtz)2(H2O)2](ClO4)2.3DMF (4).

A novel 3-D coordination polymer with trimeric copper (I) unit, [Cu(3)(CN)(IN)(2)](n)(IN = isonicotinate), was hydrothermally synthesized by the reaction of Cu(NO(3))(2).3H(2)O with isonicotinic and terephthalic acids. The structure was characterized to be a twofold interpenetrated 3-D coordination network polymer with two-coordinated copper(I). It has a powder SHG efficiency about that of KDP.

Hydrothermal synthesis under basic conditions has given a new cluster compound, Ni7(OH)8(ox)3(pip)3 (ox = oxalate; pip = piperazine). This hybrid material comprises inorganic Ni7(OH)8 clusters, which have a vertex-shared dicubane structure. These units are held together in a 3-dimensional coordination network by organic bridging ligands. Magnetic susceptibility studies suggest a ferromagnetic coupling within the cluster and an antiferromagnetic interaction between neighbouring Ni7 units. At low temperatures the material appears to undergo a magnetic phase transition to an ordered antiferromagnetic state with TN = 17 K.

Two new polymeric complexes, [Zn(pydc)]n (1) and [Co(pydc)(H2O)2]n·nH2O (2) (pydc = pyridine-3,4-dicarboxylate), have been synthesized and characterized. Complex 1 crystallizes in an acentric space group Pna21 and consists of a 3D network with unsymmetrical pydc linkers arranged in a parallel mode. Complex 2 crystallizes in the centric space group P−1, in which pydc ligands link Co(II) metal ions to generate a 2D layer structure with (4,4) topology nets. The Kurtz powder measurement shows that 1 exhibits a powder SHG efficiency about 5 times higher than that of potassium dihydrogen phosphate (KDP) and represents the first NLO-active 3D coordination network with parallel arrangement of dipolar ligands.

A series of six new bis-monodentate tectons based on the fluorene skeleton and bearing two pyridine derivatives as coordinating sites have been designed and prepared. The ability of two of them presenting a “V” type geometry to generate coordination networks in the presence of HgCl2 or CoCl2 acting as metallatectons and offering either a “V” or a square type geometry respectively was structurally studied by X-ray diffraction on single crystals. Whereas a combination of “V” shaped organic and metallic tectons leads to a 1-D coordination network, when combining a “V” shaped organic tecton with a metallatecton presenting four available coordination sites occupying the corners of a square, a 2-D neutral coordination network was obtained. In the latter case, a two-fold homo interpenetrating architecture was obtained.

The coordination network [(CuSCN)2(pym)]? (pym = pyrimidine) has been prepared and characterised by single crystal X-ray diffraction studies, revealing a new three-dimensional (CuSCN)? structural motif. The pyrimidine ligands are arranged such that the resultant coordination network is non-centrosymmetric.

A new concept of coordination network is introduced for classifying and deriving possible frameworks of tectosilicates. 26 topologically different networks have been derived by connecting points with the degree of freedom 3 in the 2nd distance. 39 different tectosilicate structures are examined in view of this coordination network.

The concept of coordination networks is introduced for classifying and deriving possible frameworks of tectosilicates, in which the nth coordination network is defined as a set of all points from topological distance 0 to n and all their connection lines. In the second network, it is possible to derive 26 different structures by connection of the points with 3 degrees of freedom; 39 different structures of tectosilicates examined were found to be distributed on the simple coordination networks. The results are compared with those of the secondary building unit criterion proposed by Meier and Breck.

Three zinc(II) coordination polymers, [Zn(4,4′-bpy)(NCS)2]n(4,4′-bpy = 4,4′-bipyridine; 1), {[Zn(4,4′-bpy)(SO4)(H2O)3]·3H2O}n (2), and {[Zn2(azpy)2(SO4)2(H2O)3]·0.5(azpy)}n (azpy = 4,4′-azopyridine; 3) have been synthesized and structurally characterized. 1 and 2 show assembled structure of one-dimensional chains, while 3 has a three-dimensional structure with pillared-layer type network. The important effect of counter anions on the coordination network was studied.

Data management is integral to sound polar science. Through analysis of documents reporting on meetings of the Arctic data management community, a set of priorities and strategies are identified. These include the need to improve data sharing, make use of existing resources, and better engage stakeholders. Network theory is applied to a preliminary inventory of polar and global data management actors to improve understanding of the emerging community of practice. Under the name the Arctic Data Coordination Network, we propose a model network that can support the community in achieving their goals through improving connectivity between existing actors.

The growth and evolution of threats, vulnerabilities, and cyber-attacks increase security incidents and generate adverse impacts on organizations. Nowadays, organizations have been strengthened in aspects of information security and information through the implementation of various technological solutions. Nevertheless, defined processes for the proper handling and coordinated management of security incidents should be established. In this paper, we propose an incident management framework that is adaptable to educational organizations and allows them to improve their management processes in the face of computer incidents. We introduce a coordination network with three levels of decision-making that defines interfaces and communication channels with supporting policies and procedures for coordination across processes and process actors. It enables different organizations to maintain focus on different objectives, to work jointly on common objectives, and to share information that supports them all in case of security incidents. Our model enables the examination of incident management processes that cross organizational boundaries, both internally and externally. This can help CSIRTs improve their ability to collaborate with other business units and other organizations when responding to incidents.