排序方式: 共有47条查询结果,搜索用时 31 毫秒
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Carolina Manzur David Carrillo Ricardo Baggio María Teresa Garland 《Journal of chemical crystallography》1997,27(6):339-342
The title compound [Mo(NNPh2)2 (acac)(PPH3)2]+OTf?, Mr=1233.1, crystallizes in the triclinic space group $P\bar 1$ , witha=12.881 (4),b=13.795(3),c=17.160(5)Å, α=90.95(1), β=91.31(1), ψ=103.53(1)°, andZ=2. The structure was solved by Patterson methods, and refined with some difficulties due to extensive disorder in the counterion. The Mo ion is hexacoordinated in an octahedral environment, with two O and two N defining the basal plane, and two P atoms in the apical sites. 相似文献
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Alexander Trujillo Mauricio Fuentealba David Carrillo Carolina Manzur Jean-René Hamon 《Journal of organometallic chemistry》2009,694(9-10):1435-1440
The synthesis of the new air and thermally stable orange neutral dinuclear iron–nickel unsymmetrical Schiff base complex, [8-(2-oxo,5-allyloxo-phenyl)-4,7-diaza-3-methyl-1-ferrocenyl-1-one-octa-1,3,7-trienato]nickel(II) (2), was achieved via the Williamson coupling reaction between the 2-oxo,5-hydroxyphenyl precursor 1 and allyl chloride in the presence of base. Complex 2 was isolated in 68% yield and characterized by IR, UV–Vis, 1H and 13C NMR spectroscopy, HRMS and authenticated by a single crystal X-ray diffraction analysis. The organometallic/inorganic hybrid complex 2 consists in a ferrocenyl fragment linked to a classical Werner-type complex made of an unsymmetrical quadridentate N2O2 Schiff base ligand with a pendant allyl ether functionality as a potential anchoring group. The Ni(II) center displays a square-planar geometry with the nitrogen and oxygen atoms occupying mutually trans positions. The structure of 2 · H2O shows that the water crystallization molecule interacts through two distinct intermolecular hydrogen bonds with the two oxygen atoms of the tetradentate N2O2 acyclic chelating ligand, forming in the solid state, a distorted six-membered ring. 相似文献
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Dario Rojas Jorge Manzur Ana María García Andrs Vega 《Acta Crystallographica. Section C, Structural Chemistry》2005,61(2):m115-m116
The title compound corresponds to a copper(II) dimer, [Cu2(OH)2(C2H3N)2(C21H22N2)2](ClO4)2, where the metal centres are μ2‐bridged by hydroxo groups. The coordination of each copper(II) centre is a slightly distorted square‐based pyramid, with two N atoms from dibenzyl(6‐methyl‐2‐pyridylmethyl)amine (BiBzMePMA) and two hydroxo O atoms occupying the basal positions, and the acetonitrile N atom at the apical position. The dimer is centrosymmetric, with a crystallographic inversion centre midway between the two Cu atoms [Cu⋯Cu = 2.9522 (9) Å] 相似文献
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Manzur J Mora H Vega A Spodine E Venegas-Yazigi D Garland MT El Fallah MS Escuer A 《Inorganic chemistry》2007,46(17):6924-6932
Two new ligands, 2-[(bis(2-pyridylmethyl)amino)methyl]-4-methylphenol (HL) and 2-[(bis(2-pyridylmethyl)amino)methyl]-4-methyl-6-(methylthio)phenol (HSL), were synthesized and were used to prepare the trinuclear copper(II) complex {[CuSL(Cl)]2Cu}(PF6)2.H2O (1) and the corresponding binuclear complexes [Cu2(SL)2](PF6)2 (2) and [Cu2L2](PF6)2 (3). The crystal structure of 1 shows two different coordination environments: two square base pyramidal centers (Cu1 and Cu1a, related by a C2 axes), acting as ligands of a distorted square planar copper center (Cu2) by means of the sulfur atom of the SCH3 substituent and the bridging phenoxo oxygen atom of the ligand (Cu2-S = 2.294 A). Compounds 2 and 3 show two equivalent distorted square base pyramidal copper(II) centers, bridged in an axial-equatorial fashion by two phenoxo groups, thus defining an asymmetric Cu2O2 core. A long copper-sulfur distance measured in 2 (2.9261(18) A) suggests a weak bonding interaction. This interaction induces a torsion angle between the methylthio group and the phenoxo plane resulting in a dihedral angle of 41.4(5) degrees. A still larger distortion is observed in 1 with a dihedral angle of 74.0(6) degrees. DFT calculations for 1 gave a ferromagnetic exchange between first neighbors interaction, the calculated J value for this interaction being +11.7 cm-1. In addition, an antiferromagnetic exchange for 1 was obtained for the second neighbor interaction with a J value of -0.05 cm-1. The Bleaney-Bowers equation was used to fit the experimental magnetic susceptibility data for 2 and 3; the best fit was obtained with J values of +3.4 and -16.7 cm-1, respectively. DFT calculations for 2 and 3 confirm the nature and the values of the J constants obtained by the fit of the experimental data. ESR and magnetic studies on the reported compounds show a weak exchange interaction between the copper(II) centers. The low values obtained for the coupling constants can be explained in terms of a poor overlap between the magnetic orbitals, due to the axial-equatorial phenoxo bridging mode observed in these complexes. 相似文献
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E. Spodine P. Valencia-Gálvez P. Fuentealba J. Manzur D. Ruiz V. Paredes-García R. Cardoso-Gil R. Kniep 《Journal of solid state chemistry》2011,184(5):1129-10892
The intercalation of the cationic binuclear macrocyclic complex [Zn2L]2+ (LH2: macrocyclic ligand obtained by the template condensation of 2-hydroxy-5-methyl-1,3-benzenedicarbaldehyde and 1,2-diaminobenzene) was achieved by a cationic exchange process, using K0.4Mn0.8PS3 as a precursor. Three intercalated materials were obtained and characterized: (Zn2L)0.05K0.3Mn0.8PS3(1), (Zn2L)0.1K0.2Mn0.8PS3(2) and (Zn2L)0.05K0.3Mn0.8PS3(3), the latter phase being obtained by an assisted microwave radiation process. The magnetic data permit to estimate the Weiss temperature θ of ≈−130 K for (1); ≈−155 K for (2) and ≈−130 K for (3). The spin canting present in the potassium precursor remains unperturbed in composite (3), and spontaneous magnetization is observed under 50 K in both materials. However composites (1) and (2) do not present this spontaneous magnetization at low temperatures.The electronic properties of the intercalates do not appear to be significantly altered. The reflectance spectra of the intercalated phases (1), (2) and (3) show a gap value between 1.90 and 1.80 eV, lower than the value observed for the K0.4Mn0.8PS3 precursor of 2.8 eV. 相似文献
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Angle J Aprile E Arneodo F Baudis L Bernstein A Bolozdynya AI Coelho LC Dahl CE DeViveiros L Ferella AD Fernandes LM Fiorucci S Gaitskell RJ Giboni KL Gomez R Hasty R Kastens L Kwong J Lopes JA Madden N Manalaysay A Manzur A McKinsey DN Monzani ME Ni K Oberlack U Orboeck J Plante G Santorelli R dos Santos JM Schulte S Shagin P Shutt T Sorensen P Winant C Yamashita M;XENON Collaboration 《Physical review letters》2011,107(5):051301
We report results of a search for light (?10 GeV) particle dark matter with the XENON10 detector. The event trigger was sensitive to a single electron, with the analysis threshold of 5 electrons corresponding to 1.4 keV nuclear recoil energy. Considering spin-independent dark matter-nucleon scattering, we exclude cross sections σ(n)>7×10(-42) cm(2), for a dark matter particle mass m(χ)=7 GeV. We find that our data strongly constrain recent elastic dark matter interpretations of excess low-energy events observed by CoGeNT and CRESST-II, as well as the DAMA annual modulation signal. 相似文献