M. I. Arriortua

Universidad del País Vasco / Euskal Herriko Unibertsitatea, Leioa, Basque Country, Spain

Are you M. I. Arriortua?

Claim your profile

Publications (330)642.54 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: The feasibility of using Crofer22APU mesh dip coated with LaNi0.6Co0.4O3−δ (LNC) ceramic paste as a uniform contact layer on a Crofer22APU channeled interconnect was studied. The control of LNC dip coating thickness on Fe–Cr mesh was carried out by rheological measurements of the suspension. SEM cross-section of formed composite contact material showed good adherence between ceramic and metallic components. The measured area specific resistance (ASR) value at 800 °C was 0.46 ± 0.01 mΩ cm2, indicating low contact resistance itself. The long term stability of metallic/ceramic composite was also studied. The contact resistance, when composite contact material was adhered to channeled Crofer22APU interconnect, was 5.40 ± 0.01 mΩ cm2, which is a suitable value for the performance of IT-SOFC stack. The stability of the system after treating at 800 °C for 1000 h was characterized using X-ray Micro-Diffraction (XRMD), Scanning Electron Microscope equipped with an Energy Dispersive X-ray analyzer (SEM-EDX) and X-ray Photoelectron Spectroscopy (XPS) techniques. The oxidation rate of the alloy and Fe3O4 phase formation were enhanced on the channels of the interconnect. Thus, the formation of CrO3 (g) and CrO2(OH)2 (g) species was accelerated on the composite surface under the channel. Through XRMD and XPS analysis the coexistence of two perovskite phases (initial LNC and Cr-perovskite) was observed.
    Journal of Power Sources 12/2014; 269:509–519. · 5.26 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: During the past years, a great effort has been devoted to the anchoring of catalysts into solid coordination networks in order to achieve heterogeneous catalysts. In this sense, an innovative approach consists on using the coordination-network synthons both as structural units and as catalysts. Regarding the latter, metalloporphyrins are suitable candidates for synthons. In fact, a few works report on coordination compounds based on metalloporphyrins exhibiting these features. On the other hand, highly distorted di-iron oxo dimers containing electron withdrawing groups rank amongst the most-effective catalyst models. Thus, the aim of this work was obtaining coordination networks based on iron porphyrins exhibiting those characteristics. This way, this work reports on the synthesis and characterisation of the μ-O-[FeTCPP]2•16DMF compound (H2TCPP = meso-tetra(4-carboxyphenyl)porphyrin, DMF = N,N-dimethylformamide). This compound is the first example of an μ-oxo dimer with TCPP. The inter-dimer connections give rise to a laminar structure. The structural, spectroscopic and magnetic properties of this compound are consistent with the presence of high-spin FeIII ions, exhibiting a strong antiferromagnetic coupling in the μ-oxo dimer (J = -132 cm-1). An unusual superhyperfine structure has been observed in EPR that is related to the high accessible volume of the compound. The structural features of the dimers and the accessible network are responsible for the excellent behaviour of the compound as a heterogeneous catalyst for different oxidation of alcohols. Therefore, this compound is a new of the very few examples of metalloporphyrins where structural units play as catalysts.
    Dalton Transactions 10/2014; · 3.81 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Spinel oxides are promising materials as protective coatings on metallic interconnects to reduce the area specific resistance (ASR) at high operating temperature in solid oxide fuel cells (SOFC). In this work, the deposition of MnCo2O4 (MC) and MnCo1.9Fe0.1O4 (MCF10) materials (1 μm) on Si substrates and commercial alloys (Crofer 22 APU, SS430 and Conicro 4023 W 188) by electron beam physical vapour deposition (EB-PVD) was studied. Optimisation of deposition, the effectiveness of MC and MCF10 protective layers and the influence of the deposition method were investigated after oxidation at 800 °C for 100 h in air. Significant improvements in Cr poisoning of the cathode and in ASR were observed in cells assembled with coated versus uncoated samples. The best results were obtained with cells assembled with MC/Conicro 4023 W 188 with MC deposited by EB-PVD.
    International Journal of Hydrogen Energy 09/2014; 39(28):15735–15745. · 3.55 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The hybrid vanadates exhibit structural archetypes between the hybrid zeotypes in which the inorganic framework is surrounding an organic cation acting as a template, and metal-organic frameworks which crystal structures are constructed from metal nodes or clusters linked by organic bridges. Here we present the summary of the work carried out in hybrid vanadates constructed from extended metal-organic arrays. The crystal structures are systematically described and classified according to the dimensionality of the inorganic and metal-organic frameworks. Finally, the magnetic, thermal and catalytic properties of different structural archetypes are discussed.
    CrystEngComm 09/2014; · 3.88 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Solid coordination frameworks (SCF) are crystalline materials based on connections between metal ions through organic ligands. In this sense, combination of polycarboxylate anions and dipyridyl ligands is an effective strategy to produce extended structures. In this context, this work is focused on two novel CuII-based SCFs exhibiting PDC (2,5-pyridinedicarboxylate) and bpe (1,2-di(4-pyridyl)ethylene): Cu2[(PDC)2(bpe)(H2O)2]•3H2O•DMF (1), and Cu[(PDC)(bpe)0.5(H2O)]•2H2O (2), where DMF is dimethylformamide. Both compounds were synthesized by slow evaporation, and their crystal structures were determined by X-ray diffraction. Further structural, thermal and magnetic characterization was carried out by means of IR, TG/DTG, DTA analysis, EPR, and measurements of the magnetic susceptibility. The crystallographic analysis revealed that compounds 1 and 2 can be described as herringbone-type layers formed by helicoidal Cu-PDC-Cu chains connected through bpe ligands. Solvent molecules are crystallized between the layers, providing the inter-layer connections through hydrogen bonds. Differences between both compounds are attributable to those solvent molecules, being indicative of the flexibility of this type of SCFs. On the other hand, due to the variety of structures found in literature that have been described as “herringbone arrays”, this work also presents a crystallochemical study based on them. The study considers stoichiometry and structural parameters leading to the identification of two types of herringbone arrays depending on the number of connections for the metal nodes (i.e. 3-and 4-connected).
    CrystEngComm 07/2014; · 3.88 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Three new fluorinated mixed valence Fe(II)–Fe(III) phosphites were synthesized by employing mild hydrothermal conditions. (H4baepn)0.5[FeIII2.3FeII1.7(H2O)2(HPO3)4−(x+y)(HPO4)x(PO4)yF4] (x [similar, equals] 0.13, y [similar, equals] 0.3) (1) (baepn = N,N′-bis(2-aminoethyl)-1,3-propanediamine (C7N4H20)) and the Co(II)-substituted phase with the formula (H4baepn)0.5[FeIII2.0FeII0.71CoII1.29(H2O)2(HPO3)4−x(HPO4)xF4] (x [similar, equals] 0.38) (2) were studied by single crystal X-ray diffraction. The phase with the major content of Co(II), (H4baepn)0.5[FeIII2.0FeII0.62CoII1.38(H2O)2(HPO3)4−x(HPO4)xF4] (x [similar, equals] 0.38) (3) was obtained as a polycrystalline powder and studied by Rietveld refinement by using the structural model of 2. These compounds were characterized by ICP-Q-MS, thermogravimetric and thermodiffractometric analyses, and XPS, IR, UV/vis and Mössbauer spectroscopy. The single crystal data indicate that phases 1 and 2 crystallize in the P21/c space group with lattice parameters a = 13.6808(4), b = 12.6340(2), c = 12.7830(3) Å and β = 116.983(4)° for 1 and a = 13.6823(4), b = 12.6063(3), c = 12.7535(4) Å and β = 116.988(4)° for 2, with Z = 4. The reciprocal space of 1 shows satellite reflections with a modulation wavevector q = 0.284(2)a* which indicate an incommensurate long-range order. The average structure of these compounds is built up by a 3D lattice constructed by inorganic layers of Fe(III) chains and Fe(II) and Co(II) dimers joined by phosphite groups partially substituted by HPO4 and PO4 tetrahedral groups. These anionic layers stack along the [100] direction encapsulating linear tetramines in eight-membered open channels involving host–guest interactions. Magnetic measurements of 1 and 3 showed antiferromagnetic coupling as the major interactions, exhibiting a weak ferromagnetic component together with a spin glass transition at low temperature in the case of 1. Heat capacity measurements showed a small anomaly at 20.5 K for 1 and a sharp magnetic peak at 28 K for 3. Unexpectedly, the small anomaly observed in 1 increased with the magnetic field and became better defined.
    CrystEngComm 05/2014; 16:6066-6079. · 3.88 Impact Factor
  • Source
  • Source
    Dataset: Revised ESI
  • [Show abstract] [Hide abstract]
    ABSTRACT: The 3D crystal structure of {Ni2(H2O)2(Bpa)2}(V6O17) (NiBpaRT), were Bpa is 1,2-bis(4-pyridil)ethane, was determined by single crystal X-ray diffraction. The crystal structure is constructed from {Ni(H2O)(Bpa)} metal−organic and (V3O8.5) vanadate chains. The connectivity of these one-dimensional units generates a three-dimensional inorganic substructure, and also a threedimensional inorganic−organic framework. The symmetric unit contains two crystallographically pseudoequivalent vanadate and metal−organic chains. The tacking of these crystallographically pseudoequivalent units seems to be nearly related to the twinning law of the crystals, and with the diffuse scattering observed in the diffraction pictures. Several models of local disorders for the packing of these one-dimensional units have been proposed to explain the origin of the diffuse scattering observed in the diffraction images. The obtained single crystals are systematically twinned. The origin of this twining is clearly related to the packing of the crystallographically independent chains along the [100] direction. The topology of the crystal structure is a new self-catenated three nodal net. The simplified structure can be described also as the natural tiling of two different tiles. NiBpaRT shows a reversible solid state transformation due to the loss of coordinated water molecules at 180 °C. The high temperature compound, {Ni2(Bpa)2}(V6O17) (NiBpaHT), maintains the crystallinity, but the solid state transformation involves a single crystal to polycrystalline reaction. So, the determination of the high temperature structure have been carried out by rigid body Rietveld refinement of the room temperature crystal structure, from synchrotron X-ray diffraction radiation. The loss of coordinated water molecules of the nickel cations is compensated by the incorporation of the terminal oxygen atoms, belonging to the adjacent VO4 tetrahedra, into the coordination environment of the nickel cations. We have referred to this mechanism of reorganization of the structural units as padlock solid state transformation. The UV−vis spectra corroborate the presence of octahedrally coordinated nickel cations in the high temperature crystal structure. The IR and Raman spectra show strong changes in the absorption maxima related to the stretching vibration of VO terminal bonds, in good agreement with the proposed padlock mechanism. The dimeric ferromagnetic coupling of the nickel cations through the VO4 tetrahedra is similar for NiBpaRT and NiBpaHT, showing also an antiferromagnetic coupling at low temperatures. However, the distortion of the nickel coordination environment during the transformation implies an important difference in the g values for NiBpaRT and NiBpaHT.
    Crystal Growth & Design 01/2014; 14:658−670. · 4.69 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The electrochemical performance of [{Mn(Bpy)}(VO3)2]≈(H2O)1.16 and [{Mn(Bpy)0.5}(VO3)2]≈(H2O)0.62 against sodium and lithium counter electrodes give rise to the structural collapse of the initial compounds. The IR and Raman studies show that the Bpy organic ligand is completely decomposed during the during the electrochemical testing. However, after the amorphization stable capacities as high as 850 mAh/g for lithium cells were achieved.
    Journal of Solid State Chemistry. 01/2014; 212:92–98.
  • Source
    Dataset: supmat
  • [Show abstract] [Hide abstract]
    ABSTRACT: M2(SeO3)F2 (M = Zn (), Mn ()) stoichiometric phases together with the Zn2-xMnx(SeO3)F2 compound doped at various concentrations (x = 0.002-0.2) were synthesized by employing mild hydrothermal conditions. These compounds have been characterized by scanning electron microscopy (SEM), Rietveld refinement of the X-ray powder diffraction patterns, ICP-Q-MS, thermogravimetric and thermodiffractometric analyses, and IR, UV/vis and electron paramagnetic resonance (EPR) spectroscopies. Compounds and crystallize in the orthorhombic Pnma space group with lattice parameters: a = 7.27903(4), b = 10.05232(6) and c = 5.26954(3) Å for the zinc species and a = 7.50848(9), b = 10.3501(12) and c = 5.47697(6) Å for the manganese phase, with Z = 4. The crystal structures of these compounds are isotypic and are built up from a 3D framework constructed by (010) sheets of [MO3F3] octahedra linked up by [SeO3] building units. Luminescence measurements of Mn2(SeO3)F2 were performed at different temperatures between 10 and 150 K. At 10 K, the emission spectrum consists of a broad band peaked at around 660 nm related to the (4)T1g → (6)A1g transition in octahedrically coordinated Mn(2+). Moreover, the influence of temperatures up to 295 K and the Mn concentration on the luminescent properties of the Zn2-xMnx(SeO3)F2 system were systematically studied. Magnetic measurements of show antiferromagnetic coupling as the major interactions exhibiting a spin canting at low temperature.
    Dalton Transactions 07/2013; · 3.81 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Compound ([FeTPPbipy](•))n (TPP = meso-tetraphenylporphyrin and bipy = 4,4'-bipyridine) is the first example of a Fe-TPP-bipy coordination network, and it consists of 1D polymers packed through face-to-face and edge-to-face π-π interactions. The compound has been investigated by means of X-ray diffraction, IR, Mössbauer, UV-visible, and EPR spectroscopies, thermogravimetry, magnetic susceptibility measurements, and quantum-mechanical density functional theory (DFT) and time-dependent DFT calculations. The chemical formula for this compound can be confusing because it is compatible with Fe(II) and TPP(2-) anions. However, the spectroscopic and magnetic properties of this compound are consistent with the presence of low-spin Fe(III) ions and [FeTPPbipy](•) neutral radicals. These radicals are proposed to be formed by the reduction of metalloporphyrin, and the quantum-mechanical calculations are consistent with the fact that the acquired electrons are located on the phenyl groups of TPP.
    Inorganic Chemistry 06/2013; · 4.59 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: In order to simulate the contact situation of interconnect/contact layer/cathode in SOFC stacks, contact resistance and chemical compatibility of LaNi0.6Co0.4O3–δ (LNC) as contact layer between Crofer22APU interconnect and La0.6Sr0.4FeO3 (LSF) cathode was investigated at 800 °C in air for more than 1300 h using X-ray diffraction (XRD), scanning electron microscopy (SEM) set-up equipped with an energy dispersive X-ray analyser (EDX) and area specific resistance (ASR) measurements. The XRD analysis reveals that multiple phases were formed during ASR test. The point microanalysis on cross-section of Fe–Cr/LNC/LSF system, after ASR measurements, shows chromium within the porous contact material mainly concentrated close to interconnect, but no Cr, Ni, or Co was detected in the cathode. It was found between LNC and LSF cathode, a thin and uniform layer which contains Sr, La, Cr, Co, Ni, and Fe. The contact between layers could act as a physical barrier for element migration and thus can suppress degradation of the cathode for these systems. The area specific resistance slope depends on the interactions between the contact material and/or cathode and the interconnect. Co-containing spinels formed during ASR test can be responsible of the resistance decrease of the system, related to the low degradation of the cell.
    Fuel Cells 06/2013; 13(3). · 1.55 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Two new CoP–bipy compounds have been synthesised and characterised, where P is TPP for compound 1 (TPP = meso-tetraphenylporphyrin) and TPPS for compound 2 (TPPS = meso-tetraphenylporphine-tetrasulfonic acid tetrasodium salt), and bipy is 4,4′-bipyridine. Compound 1 consists of 1D polymers packed in a network where isolated porphyrin units are immobilized by an extended π-bond system. On the other hand, as we are aware, compound 2 is the first Co–TPPS compound in literature. It also consists of 1D polymers that are formed by the alternation of two distinct metal centres. These unprecedented polymers are packed forming cavities where crystallization molecules of water are located. The robustness of the hydrogen bond system and a topology based on interpenetrated nets are responsible for the high thermal stability of compound 2. Additionally, a crystallochemical study confirmed the existence of a correlation between the degree of ruffled distortion of the porphyrin macrocycle and some selected dihedral angles and distances for CoII porphyrins in literature.
    CrystEngComm 04/2013; 15(20):4181-4188. · 3.88 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Four isomorphic compounds with formula [{Co(HO)(Bpe)}(VO)]·4HO·Bpe, CoBpe 1; [{CoNi(HO)(Bpe)}(VO)]·4HO·Bpe, CoNiBpe 2; [{CoNi(HO)(Bpe)}(VO)]·4HO·Bpe, NiCoBpe 3; and [{Ni(HO)(Bpe)}(VO)]·4HO·Bpe, NiBpe 4, have been obtained by hydrothermal synthesis. The crystal structures of CoBpe 1 and NiBpe 4 were determined by single-crystal X-ray diffraction (XRD). The Rietveld refinement of CoNiBpe 2 and NiCoBpe 3 XRD patterns confirms that those are isomorphic. The compounds crystallize in the P1̅ space group, exhibiting a crystal structure constructed from inorganic layers pillared by Bpe ligands. The crystal structure contains intralayer and interlayer channels, in which the crystallization water molecules and Bpe guest molecules, respectively, are located. The solvent molecules establish a hydrogen bonding network with the coordinated water molecules. Thermodiffractometric and thermogravimetric studies showed that the loss of crystallization and coordinated water molecules takes place at different temperatures, giving rise to crystal structure transformations that involve important reduction of the interlayer distance, and strong reduction of crystallinity. The IR, Raman, and UV-vis spectra of the as-synthesized and heated compounds confirm that the structural building blocks and octahedral coordination environment of the metal centers are maintained after the structural transformations. The color change and reversibility of the water molecules uptake/removal were tested showing that the initial color is not completely recovered when the compounds are heated at temperatures higher than 200 °C. The thermal evolution of the magnetic susceptibility indicates one-dimensional antiferromagnetic coupling of the metal centers at high temperatures. For NiCoBpe 3 and NiBpe 4 compounds magnetic ordering is established at low temperatures, as can be judged by the maxima observed in the magnetic susceptibilities. CoNiBpe 2 was proved as catalyst being active for cyanosilylation reactions of aldehydes.
    Inorganic Chemistry 03/2013; 52(5):2615-26. · 4.59 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: Four novel amine templated open-framework vanadium(iii) phosphites with the formula (C(5)N(2)H(14))(0.5)[V(H(2)O)(HPO(3))(2)], (C(5)N(2)H(14) = 2-methylpiperazinium), and (L)(4-x)(H(3)O)(x)[V(9)(H(2)O)(6)(HPO(3))(14-y)(HPO(4))(y)(H(2)PO(3))(3-z)(H(2)PO(4))(z)]·nH(2)O (, L = cyclopentylammonium, x = 0, y = 3.5, z = 3, n = 0; , L = cyclohexylammonium, x = 1, y = 0, z = 0.6, n = 2.33; , L = cycloheptylammonium, x = 1, y = 0, z = 0, n = 2.33) were synthesized employing solvothermal reactions and characterized by single-crystal X-ray diffraction, ICP-AES and elemental analyses, thermogravimetric and thermodiffractometric analyses, and IR and UV/vis spectroscopy. Single-crystal data indicate that crystallizes in the triclinic system, space group P1[combining macron], whereas , and crystallize in the hexagonal space group P6(3)/m. Compound has a two-dimensional motif with anionic sheets of [V(H(2)O)(HPO(3))(2)](-) formula, whose charge is compensated by the 2-methylpiperazinium cations embedded between the layers. In contrast, , and present a pillar-layer network giving rise to a three-dimensional framework containing intersecting 16-ring channels with the primary amine templates and the crystallization water molecules enclosed in them. , , and behave as heterogeneous catalysts for the selective oxidation of alkyl aryl sulfides, with tert-butylhydroperoxide (TBHP) as the oxidizing agent, being active, selective and recyclable for several successive cycles of reaction.
    Dalton Transactions 01/2013; · 3.81 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The three-dimensional Co(pym)(VO(3))(2), , hybrid compound, where pym is pyrimidine, has been synthesized under mild hydrothermal conditions at 120 °C. The compound has been characterized by FT-IR spectroscopy, elemental analysis, thermogravimetric measurements, thermodiffractometry, UV-Vis spectroscopy, temperature-dependent magnetic susceptibility and magnetization, and finally a study of specific heat has been performed. The crystal structure of was solved using single-crystal X-ray diffraction data, taking into account that the crystals of this compound are twins of two components. It crystallizes in the monoclinic system, space group C2/c, a = 12.899(5) Å, b = 9.859(2) Å, c = 7.051(1) Å, β = 111.41(3)°, Z = 4. The crystal structure is built up from edge sharing VO(5) trigonal bipyramid double chains and [CoO(4)pym](n) chains. This resembles the structure of the [Co(H(2)O)(2)(VO(3))(2)]·2H(2)O compound, . For this reason a comparative study of their properties was carried out. Magnetic measurements of , performed in the 2.0 to 300 K range, reveal the existence of a weak ferromagnetic order near 3 K. This fact was confirmed with magnetization measurements, which show irreversibility characteristic of soft ferromagnets. Magnetic measurements of show a 3D antiferromagnetic ordering at 2.5 K. The magnetization shows a small change of curvature indicating the occurrence of a metamagnetic transition. Specific heat measurements of both compounds confirm the 3D nature of the magnetic order. The comparative study of the magneto-structural correlations reveals that the pyrimidine molecules are responsible for the different magnetic behaviour between and .
    Dalton Transactions 10/2012; · 3.81 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The 3D hybrid compounds {Co(Bpa)}(VO3)2 (1) and [{Ni(H2O)(Bpa)}(VO3)2]·2H2O (2), where Bpa is 1,2-di(4-pyridil)ethane, have been synthesized using mild hydrothermal conditions. The compositional diagrams for the Co(II)/Bpa/VxOy and Ni(II)/Bpa/VxOy systems have been constructed and qualitative crystallization sequences have been proposed. The 3D crystal structures of both compounds are closely related, and are constructed of inorganic layers pillared by the organic ligand. The UV-vis spectra for (1) shows the characteristic bands of the Co(II) d7high-spin cation in a slightly distorted trigonal bipyramid geometry. The thermal behaviour of (1) allows the determination of the expansion coefficients for the cell and angle parameters, which were closely related to the different types of bonds that exist in the crystal structure. The cobalt compound exhibits antiferromagnetic coupling of the cobalt centres within the inorganic layers, probably coupled in dimeric units, as is expected for the different magnetic exchange pathways. For (2), the diffuse scattering is probably related to the motion of the crystallization water molecules, which is observed in the (h0l), (h2l), (hk0) and (hk2) planes.
    CrystEngComm 09/2012; 14(20):6921-6933. · 3.88 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: The hydrothermal treatment of Ni(NO(3))(2)·6H(2)O, NaVO(3), and Bpa (1,2-Di(pyridyl)ethane) (C(12)H(12)N(2)) at 120 °C during 3 days leads to green single crystals of the title compound. The single crystal X-ray diffraction reveals that [{Ni(3)(H(2)O)(3)(Bpa)(4)}(V(6)O(18))]·8H(2)O crystallizes in the monoclinic system, P2(1)/c space group, with a = 13.5536 (2), b = 19.0463 (2), c = 27.7435 (3) Å, β = 112.3880 (10)°, V = 6622(3) Å(3), with R1(obs) = 0.0558, wR2(obs) = 0.1359, for 10278 observed reflections. The complexity of the crystal structure is based on different points, as the existence of: both "gauche" and "trans" conformations of the organic ligand, the [V(12)O(36)](-12) cycles, formed by 12 corner-sharing VO(4) tetrahedra, and, finally, the combination of both three-dimensional metal-organic and inorganic substructures, giving rise to a self-catenated highly connected net. The crystallization water molecules are semi-encapsulated in the channels along the [100] direction, and their loss gives rise to a dynamical and reversible structural contraction. Moreover, after the removal of the crystallization water molecules, the compound exhibits a negative thermal behavior in the 85-155 °C temperature range, and irreversible structural transformation due to the loss of coordinated water molecules up to 200 °C. The IR and UV-vis spectra were determined for the as-synthesized sample, after the removal of crystallization water molecules and after the irreversible transformation due to the loss of coordinated water molecules. The thermal evolution of χ(m) was adjusted to a magnetic model considering an isotropic dimer plus two Ni(II) d(8) isolated octahedra.
    Inorganic Chemistry 02/2012; 51(4):2130-9. · 4.59 Impact Factor

Publication Stats

667 Citations
642.54 Total Impact Points

Institutions

  • 1982–2014
    • Universidad del País Vasco / Euskal Herriko Unibertsitatea
      • • Mineralogy and Petrology
      • • Facultad de Ciencia y Tecnología
      • • Departamento de Química Inorgánica
      • • Organic Chemistry II
      Leioa, Basque Country, Spain
  • 1999–2008
    • Universidad de Burgos
      • Department of Chemistry
      Burgos, Castile and Leon, Spain
  • 2001
    • Universidad Nacional del Litoral
      Ciudad de Santa Fe, Santa Fe, Argentina
  • 1993
    • University of Bordeaux
      Burdeos, Aquitaine, France
  • 1987
    • University of Valencia
      • Inorganic Chemistry
      Valencia, Valencia, Spain