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Crystalline powder aggregates of a new nickel coordination polymer with 2-carboxyethylphosphonic acid (HPPAH) and 4,4′-bipyridine, Ni(HPPA)(4,4′-bipy)(HO), has been obtained by hydrothermal synthesis, and their crystal structure has been ab initio determined from synchrotron powder data. The compound shows a layer structure in bc plane, with Ni atoms in two different environments. The loss of the coordinated water by heating leads to the apparition of an anhydrous phase, which remains stable when cooling down to room temperature. Synthesized material presents a paramagnetic behaviour with weak antiferromagnetic interactions and zero-field splitting at low temperature (T < 50 K)., The authors thank financial support from Spanish Ministerio de Ciencia e Innovación (MAT2013-40950-R), Gobierno del Principado de Asturias (GRUPIN14-060), and ERDF. E.F-Z. thanks the Programa Severo Ochoa – FICyT for her pre-doctoral grant (BP 11-142).

A new hetero-metallic polymer, NiCd(cit)(H2O) (cit = citrate), was synthesized under hydrothermal conditions. The structural analysis indicates the formation of a 2D structure, bridged by the cit4- group. This compound crystallizes in the monoclinic P21/c space group, with lattice parameters: a = 6.0817(3) Å, b = 14.9725(6) Å, c = 9.6817(5) Å, ß = 101.353(5)°. Full characterization by powder diffraction analysis, thermocalorimetry and scanning electron microscopy, XPS and fluorescence have been carried out. The TG-MS and DSC results show that this compound is thermally stable up to 250 °C and the DSC profile shows a medium-intense endotherm centred at approximately 300 °C. The distances of Cd-O are in the range of 2.169(4)-2.647(4) Å, similar to pure cadmium(II)-citrate aqueous complex Cd(C6H6O7)(H2O). The six-coordinated Cd2+ is linked by carboxylate groups to form an infinite chain, which is further connected through NiO6 octahedral bridges to generate 2D structure in the bc plane., Financial support from Spanish Ministerio de Economia y Competitividad (MAT2010-15094, MAT2013-40950-R, Factoría de Cristalización—Consolider Ingenio 2010) and ERDF funding is acknowledged.

Three new zinc(II) coordination polymers, [Zn(HO3PCH2CH2COO)(C12H8N2)(H2O)] (1), [Zn3(O3PCH2CH2COO)2(C12H8N2)](H2O)3.40 (2) and [Zn5(HO3PCH2CH2COO)2(O3PCH2CH2COO)2(C12H8N2)4](H2O)0.32 (3), with different structural dimensionality (0D, 2D and 3D, respectively) have been prepared by hydrothermal synthesis, and their structures were determined by single-crystal X-ray diffraction. Compound 1 crystallizes in the monoclinic system (P21/c) forming discrete dimeric units bonded through H-bonds, while compounds 2 and 3 crystallize in the triclinic (P−1) and the monoclinic (C2/c) systems, respectively. Compound 3, showing three different coordination numbers (4, 5 and 6) for the zinc atoms, has also been obtained by thermal treatment of 1 (probed by high-temperature XRPD experiments). The crystalline features of these compounds, related to the coordination environments for the zinc atoms in each structure, provoke the increase of the relative fluorescence for 2 and 3, compared to the free phenanthroline. Thermal analysis (TG and DSC) and XPS studies have been also carried out for all compounds., We thank financial support from Spanish Ministerio de Economía y Competitividad (MAT2010-15094, MAT2013-40950-R, Factoría de Cristalización Consolider Ingenio 2010) and ERDF. E.F-Z. thanks the Programa Severo Ochoa—FICyT for her pre-doctoral grant (BP 11-142).

Lanthanide–organic frameworks based on 2,5-pyridinedicaboxylate (25p) ligand, formulated as [Yb4(OH)4(25p)4(H2O)3]·H2O (25pYb), [Y4(OH)4(25p)4(H2O)3]·H2O (25pY-1) and [Y6(OH)8(25p)5(H2O)2] (25pY-2), have been obtained as single phases under hydrothermal conditions. 25pYb and 25pY-1 are isostructural, and crystallize in the triclinic space group, P-1, with a=8.6075(5) Å, b=14.8478(7) Å, c=15.9164(9) Å, α=86.277(4)°, β=80.196(5)°, γ=81.785(4)°, and a=8.7166(6) Å, b=14.966(1) Å, c=15.966(1) Å, α=86.260(6)°, β=80.036(6)°, γ=81.599(6)°, respectively. 25pY-2 crystallizes in the monoclinic space group, P21/c, with a=24.9117(17) Å, b=13.7340(8) Å, c=14.3385(10) Å, β=100.551(7)°. 25pYb and 25pY-2 have been structurally characterized by single-crystal X-ray diffraction. The 25pYb structure is based on tetranuclear cubane-like [Yb4(OH)4]8+ clusters, which are interconnected to eight neighbouring clusters through teen surrounding 25p ligands leading to neutral 3D framework, while the structure of 25pY-2 is based on two independent cuban-like [Y4(OH)4]8+ clusters, which are joined together through Y1 cation leading to the formation of hexanuclear [Y6(OH)8]10+ clusters, which in turn are joined via Y2 cation resulting in infinite inorganic chain extending along c-axis, and each chain is interconnected to six adjacent chains through 25p ligands leading finally to 3D framework. The luminescence properties of Eu3+ and Tb3+ doped 25pY-1 and 25pY-2 compounds have also been investigated. All materials has been characterized by powder X-ray diffraction, thermal analyses (TG–SDTA–MS), FTIR spectroscopy, C–H–N elemental analysis, scanning electron microscopy (SEM-EDX), and powder X-ray thermodiffraction., Financial support from Spanish Ministerio de Economía y Competitividad (MAT2013-40950-R, and FPI grant BES-2011-046948 to MSM.A.) and Gobierno del Principado de Asturias (GRUPIN14-060), and FEDER funding are acknowledged.

Co2(HO3PCH2CH2COO)2(C12H8N2)2 has been synthesized from [Co2(HO3PCH2CH2COO)2(C12H8N2)2(μ-OH2)](H2O) by thermal treatment (350 °C) under inert atmosphere (N2). The transformation between the initial compound to a red-pink crystalline solid is mediated by an intermediate blue amorphous material. Co2(HO3PCH2CH2COO)2(C12H8N2)2 is stable in air until 440 °C, showing some trends of being magnetically ordered below 2 K., We thank financial support from Spanish Ministerio de Ciencia e Innovación (MAT2010-15094, MAT2008-06542-C04, MAT2006-01997, Factoría de Cristalización – Consolider Ingenio 2010) and FEDER.

Three non-isostructural metal(II) coordination polymers (metal=copper, cobalt, cadmium) were synthesized under the same mild hydrothermal conditions (T=408 K) by mixture of the corresponding metal acetate with 2-carboxyethylphosphonic acid and 1,10-phenanthroline (1:1:1 M ratio) and their structures were determined by single-crystal X-ray diffraction. Cu2(HO3PCH2CH2COO)2(C12H8N2)2(H2O)2 and Cd2(HO3PCH2CH2COO)2(C12H8N2)2 are triclinic (space group P-1) with a=7.908(5) Å, b=10.373(5) Å, c=11.515(5) Å, α=111.683(5)°, β=95.801(5)°, γ=110.212(5)° (T=120 K), and a=8.162(5) Å, b=9.500(5) Å, c=11.148(5) Å, α=102.623(5)°, β=98.607(5)°, γ=113.004(5)° (T=293 K), respectively. In contrast, [Co2(HO3PCH2CH2COO)2(C12H8N2)2(μ–OH2)](H2O) is orthorhombic (space group Pbcn) with a=21.1057(2) Å, b=9.8231(1) Å, c=15.4251(1) Å (T=120 K). For these three compounds, structural features, including H-bond network and the π–π stacking interactions, and thermal stability are reported and discussed. None of the materials present a long-range magnetic order in the range of temperatures investigated from 300 K down to 1.8 K. © 2011 Elsevier Inc. All rights reserved.

12 páginas, 4 figuras, 1 tabla., In the title compound, C13H12N4O, the semicarbazone fragment links a benzene and a pyridine ring in the structure. The crystal packing is stabilized by strong intermolecular N-HO hydrogen bonds, which connect two molecules to form a synthon unit, and by N-HN hydrogen bonds and weak C-H interactions. The molecular conformation is stabilized by intramolecular N-HN and C-HO interactions., Financial support by the Agencia Española de Cooperación Internacional y Desarrollo (AECID), FEDER funding, the Spanish MICINN (MAT2006–01997, MAT2010-15094 and the Factoría de Cristalización Consolider Ingenio 2010), the Gobierno del Principado de Asturias (PCTI), the University of Oviedo and Banco Santander is acknowledged.

In the title compound, C14H13N3S·H2O, the thiosemicarbazide group is nearly planar, with a maximum deviation of 0.072 (2) Å from the ideal least-squares plane, and shows an E conformation. In the crystal packing, the water molecules are involved in an extensive intermolecular N-HO hydrogen-bond network, assisted by O-HS interactions, which link the independent molecules into chains extended along b axis. An intramolecular hydrogen N-HN bond helps to stabilize the molecular conformation., Financial support by the Agencia Española de Cooperación Internacional y Desarrollo (AECID), FEDER funding, Spanish MICINN (MAT2006–01997 and Factoría de Cristalización Consolider Ingenio 2010), Gobierno del Principado de Asturias (PCTI) and Banco Santander is acknowledged.