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Tris(tetrabutylammonium) hexakis(tert-butanethiolato-κS)hepta-μ3-chlorido-μ3-sulfido-hexamolybdate dihydrate
Pavel A. Petrov,Dmitry Yu. Naumov,Sergey N. Konchenko
Acta Crystallographica Section E , 2012, DOI: 10.1107/s1600536812007416
Abstract: The octahedral cluster core of the anion in the structure of the title compound, (C16H36N)3[Mo6(C4H9S)6(μ3-Cl)7(μ3-S)]·2H2O, has -3 site symmetry. Two μ3-Cl atoms fully occupy positions in the cluster core, while the remaining six positions are statistically occupied by Cl and S atoms in a 1:5 ratio. The fully occupied Cl-atom positions are located on sites with 3 symmetry, and the N atom of tetrabutylammonium cation is located on a site with 2 symmetry. The structure contains also two disordered solvent water molecules, one of which is located on a threefold rotation axis and the other in a general position, both with an occupancy of 0.25. The water molecules are localized in cavities formed by the tetrabutylammonium cations and the tert-butanethiolate groups. The metal clusters are stacked in a cubic close packing arrangement along [001].
Penta-Hepta Defect Motion in Hexagonal Patterns  [PDF]
Lev S. Tsimring
Physics , 1995, DOI: 10.1103/PhysRevLett.74.4201
Abstract: Structure and dynamics of penta-hepta defects in hexagonal patterns is studied in the framework of coupled amplitude equations for underlying plane waves. Analytical solution for phase field of moving PHD is found in the far field, which generalizes the static solution due to Pismen and Nepomnyashchy (1993). The mobility tensor of PHD is calculated using combined analytical and numerical approach. The results for the velocity of PHD climbing in slightly non-optimal hexagonal patterns are compared with numerical simulations of amplitude equations. Interaction of penta-hepta defects in optimal hexagonal patterns is also considered.
Penta-hepta defect chaos in a model for rotating hexagonal convection  [PDF]
Yuan-Nan Young,Hermann Riecke
Physics , 2002, DOI: 10.1103/PhysRevLett.90.134502
Abstract: In a model for rotating non-Boussinesq convection with mean flow we identify a regime of spatio-temporal chaos that is based on a hexagonal planform and is sustained by the {\it induced nucleation} of dislocations by penta-hepta defects. The probability distribution function for the number of defects deviates substantially from the usually observed Poisson-type distribution. It implies strong correlations between the defects inthe form of density-dependent creation and annihilation rates of defects. We extract these rates from the distribution function and also directly from the defect dynamics.
Octakis[2,2′,5,5′-tetrathiafulvalenium(0.5+)] bis[hexamolybdate(2−)] acetonitrile solvate
Ikram Zebiri,Berkahoum Anak,Yacine Djebli,Sihem Boufas
Acta Crystallographica Section E , 2009, DOI: 10.1107/s1600536809031092
Abstract: The asymmetric unit of the title compound, (C6H4S4)8[Mo6O19]2·CH3CN, contains two halves of two centrosymmetric [Mo6O19]2 hexamolybdate anions, which are each built up from six distorted MoO6 octahedra sharing common edges and one common vertex at the central O atom, six tetrathiafulvalene cations (three of which are located on mirror planes) to balance the charge and a half of an acetonitrile solvent molecule, likewise located on a mirror plane. The two central hexamolybdate O atoms occupy special positions 2a and 2d, respectively. The cations and anions are interlinked through C—H...O contacts.
Lung Surfactant Levels are Regulated by Ig-Hepta/GPR116 by Monitoring Surfactant Protein D  [PDF]
Taku Fukuzawa, Junji Ishida, Akira Kato, Taro Ichinose, Donna Maretta Ariestanti, Tomoya Takahashi, Kunitoshi Ito, Jumpei Abe, Tomohiro Suzuki, Shigeharu Wakana, Akiyoshi Fukamizu, Nobuhiro Nakamura, Shigehisa Hirose
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0069451
Abstract: Lung surfactant is a complex mixture of lipids and proteins, which is secreted from the alveolar type II epithelial cell and coats the surface of alveoli as a thin layer. It plays a crucial role in the prevention of alveolar collapse through its ability to reduce surface tension. Under normal conditions, surfactant homeostasis is maintained by balancing its release and the uptake by the type II cell for recycling and the internalization by alveolar macrophages for degradation. Little is known about how the surfactant pool is monitored and regulated. Here we show, by an analysis of gene-targeted mice exhibiting massive accumulation of surfactant, that Ig-Hepta/GPR116, an orphan receptor, is expressed on the type II cell and sensing the amount of surfactant by monitoring one of its protein components, surfactant protein D, and its deletion results in a pulmonary alveolar proteinosis and emphysema-like pathology. By a coexpression experiment with Sp-D and the extracellular region of Ig-Hepta/GPR116 followed by immunoprecipitation, we identified Sp-D as the ligand of Ig-Hepta/GPR116. Analyses of surfactant metabolism in Ig-Hepta+/+ and Ig-Hepta?/? mice by using radioactive tracers indicated that the Ig-Hepta/GPR116 signaling system exerts attenuating effects on (i) balanced synthesis of surfactant lipids and proteins and (ii) surfactant secretion, and (iii) a stimulating effect on recycling (uptake) in response to elevated levels of Sp-D in alveolar space.
[(2,3,5,6-η)-Bicyclo[2.2.1]hepta-2,5-diene]dibromidopalladium(II)  [cached]
Nam-Ho Kim,Kwang Ha
Acta Crystallographica Section E , 2009, DOI: 10.1107/s1600536809020583
Abstract: In the title complex, [PdBr2(C7H8)], the PdII ion lies in a distorted square-planar environment defined by the two Br atoms and the mid-points of the two π-coordinated double bonds of bicyclo[2.2.1]hepta-2,5-diene. The complex is disposed about a crystallographic mirror plane parallel to the ac plane passing through the Pd, Br atoms and the centre of the diene ligand.
Recent advances in the chemistry of gold(I) complexes with C-, N- and S-donor ligands Part II: Sulfur ylide, hydrosulfido, sulfido, trithiocarbonato, dithiocarbimato and 1, 1-ethylenedithiolato derivatives
José Vicente,M Teresa Chicote,M Dolores Abrisqueta,Pablo González-Herrero,Rita Guerrero
Gold Bulletin , 1998, DOI: 10.1007/BF03214777
Abstract: In these two papers we report the chemistry of gold(I) complexes with C-, N-, and S-donor ligands, as recently published by our group, and describe some previously unpublished results. In Part I, the synthesis of alkynyl, amino, imino and nitrido gold(I) complexes was reported (1). In this part, we give an account of the synthesis of gold(I) complexes with sulfur-containing ligands such as sulfur ylides, hydrosulfido, sulfido, trithiocarbonato, dithiocarbimato and 1, 1-ethylenedithiolato.
A new mono-functionalized organoimido hexamolybdate derivative: bis(tetra-n-butylammonium) (5-chloro-2-methylphenylimido)-μ6-oxido-dodeca-μ2-oxido-pentaoxidohexamolybdate(VI)
Qiang Li,Zichen Xiao,Liye Chen,Jin Zhang
Acta Crystallographica Section E , 2011, DOI: 10.1107/s1600536811036063
Abstract: The title complex, [(C4H9)4N]2[Mo6(C7H6ClN)O18], was prepared by the reaction of (Bu4N)4[α-Mo8O26] and 2-methyl-5-chloroaniline hydrochloride with N,N′-dicyclohexylcarbodiimide as dehydrating agent in dry acetonitrile solution. The arylimido ligand is linked to an Mo atom of the Lindqvist-type hexamolybdate anion by an Mo[triple-bond]N triple bond, with a bond length of 1.732 (4) and an Mo[triple-bond]N—C bond angle of 169.1 (4)°, typical for monodentate imido groups in such hybrid complexes. Due to the interaction between one H atom in the aryl group and an O atom of a symmetry-related hexamolybdate cluster, the anions form centrosymmetric dimers in the crystal structure. Weak C—H...O contacts are observed between the cations and anions. Unresolved disorder in some of the butyl chains of the ammonium cation is noted.
A NEW LINDQVIST-TYPE HEXAMOLYBDATE CLUSTER FUNCTIONALIZED WITH THE jt-DONOR LIGAND 4-BROMO-2,6-DIMETHYLPHENYLIMIDO: SPECTROSCOPIC, ELECTROCHEMICAL AND STRUCTURAL STUDIES
CORTéS,MARCELA; FUENTEALBA,MAURICIO; MANZUR,CAROLINA; CARRILLO,DAVID;
Journal of the Chilean Chemical Society , 2008, DOI: 10.4067/S0717-97072008000100004
Abstract: a new ionic organic-inorganic hybrid complex of formula (?-bu4n)2[mo(?018(nr)]1/2me2co, r = -c6h2-2,6-me2-4-br, (w-bu4n)2[l]-i4me2co, has been prepared in acetonitrile by reacting tetrabutylammonium a-octamolybdate, (?-bu4n)4[0t-mo8o26], with 2,6-dimethyl-4-bromoaniline hydrochloride, 2,6-me2-4-br-c6h2nh2hcl, using n,n'-dicyclohexylcarbodiimide, (c6hu)n=c=n(c6h11), as dehydrating agent. this complex, formulated as (?-bu4n)2[l]1/2me2co, contains a c-br group which can be functionahzed for constructing novel hybrid materials. the complex was fully characterized by ir, uv-vis, 'h- and "c-nmr spectroscopies, and authenticated by single crystal x-ray diffraction analysis. the asymmetric unit contains two crystallographically independent anions, [l]2", differing by the orientation of the phenyl ring relative to the hexamolybdate skeleton, and one molecule of acetone. both molecules differ in the angles mo(l)-n(l)-c(l)= 172.2(6) and mo(7)-n(2)-c(9)= 175.6(6)°. these angles, near to 180°, indicate the presence of a mo=n triple bond
A NEW LINDQVIST-TYPE HEXAMOLYBDATE CLUSTER FUNCTIONALIZED WITH THE jt-DONOR LIGAND 4-BROMO-2,6-DIMETHYLPHENYLIMIDO: SPECTROSCOPIC, ELECTROCHEMICAL AND STRUCTURAL STUDIES  [cached]
MARCELA CORTéS,MAURICIO FUENTEALBA,CAROLINA MANZUR,DAVID CARRILLO
Journal of the Chilean Chemical Society , 2008,
Abstract: A new ionic organic-inorganic hybrid complex of formula ( -Bu4N)2[Mo( 0(18)(NR)]1/2Me2CO, R = -C6H2-2,6-Me2-4-Br, (w-Bu4N)2[l]-i4Me2CO, has been prepared in acetonitrile by reacting tetrabutylammonium a-octamolybdate, ( -Bu4N)4[0t-Mo8O26], with 2,6-dimethyl-4-bromoaniline hydrochloride, 2,6-Me2-4-Br-C6H2NH2HCl, using N,N'-dicyclohexylcarbodiimide, (C6H U)N=C=N(C6H11), as dehydrating agent. This complex, formulated as ( -Bu4N)2[l]1/2Me2CO, contains a C-Br group which can be functionahzed for constructing novel hybrid materials. The complex was fully characterized by IR, UV-Vis, 'H- and "C-NMR spectroscopies, and authenticated by single crystal X-ray diffraction analysis. The asymmetric unit contains two crystallographically independent anions, [l]2", differing by the orientation of the phenyl ring relative to the hexamolybdate skeleton, and one molecule of acetone. Both molecules differ in the angles Mo(l)-N(l)-C(l)= 172.2(6) and Mo(7)-N(2)-C(9)= 175.6(6)°. These angles, near to 180°, indicate the presence of a Mo=N triple bond
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