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101.
D. N. Dybtsev M. P. Yutkin E. V. Peresypkina A. V. Virovets Y. Hasegawa H. Nishihara V. P. Fedin 《Russian Chemical Bulletin》2007,56(9):1782-1786
The reaction of Co(NO3)2·6H2O with 1,3,5-benzenetricarboxylic acid (H3btc, trimesic acid) in DMF at 100 °C afforded the coordination polymer [Co3(dmf)6(btc)(Hbtc)(H2btc)]··9H2O (1) (dmf is N,N′-dimethylformamide, DMF). According to the X-ray diffraction study, the metal-organic coordination polymer is composed of
planar honeycomb (6,3) networks, in which the organic benzenetricarboxylate anions and the inorganic Co2+ cations play a role of three-connected nodes. Disordered water molecules are intercalated between the layers. A study of
the magnetic properties showed the presence of a weak antiferromagnetic coupling between the Co2+ ions (S = 3/2).
Dedicated to Academician G. A. Abakumov on the occasion of his 70th birthday.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1719–1723, September, 2007. 相似文献
102.
Allais C. Keller G. Lesieur P Ollivon M. Artzner F. 《Journal of Thermal Analysis and Calorimetry》2003,74(3):723-728
Polymorphism of trilaurin mixed with 4% of cholesterol was studied with a setup coupling calorimetry and phase characterisation
by in-situ X-ray diffraction (Microcalix). Four polymorphic forms were identified. Monotropic and enantiotropic transitions
were identified from the reconstruction of Gibbs free energy diagram which allows the control of trilaurin polymorphism.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
103.
E. V. Chubarova D. G. Samsonenko H. G. Platas F. M. Dolgushin A. V. Gerasimenko M. N. Sokolov Z. A. Starikova M. Yu. Antipin V. P. Fedin 《Journal of Structural Chemistry》2004,45(6):1004-1013
Compounds of trigonal cluster chloroaqua complexes with cucurbit[8]uril were synthesized by slowly evaporating HCl solutions of chalcogenides heterometallic cubane cluster complexes of molybdenum and tungsten with cucurbit[8]uril in air; the complexes were characterized by X-ray diffraction analysis: (H3O)8[Mo3S4(H2O)2.5Cl6.5]2Cl(PdCl4)·(C48H48N32O16)· 29H2O (a = 13.3183(17) Å, b = 13.7104(18) Å, c = 18.225(3) Å; α = 80.263(3)°, β = 77. 958(3)°, γ = 87.149(4)°, V = 3207.4(7) Å3, space group P
, Z = 1, ρ(calc) = 1.900 g/cm3), (H3O)4 [Mo3S4(H2O)3Cl6]2·(C48H48N32O16)3·68H2O (a = 21.413(6) Å, c = 49.832(10) Å; γ = 120°, V = 19788(8) Å3, space group R
, Z = 3, ρ(calc) = 1.695 g/cm3), (H3O)6 [Mo3S4(H2O)3Cl6]2Cl2·(C48H48N32O16)·12H2O (a = 15.881(2) Å, b = 17.191(2) Å, c = 23.276(4) Å; β = 98.865(15)°, V = 6278.7(15) Å3, space group P21/c, Z = 2, ρ(calc) = 1.638 g/cm3), [W3S4(H2O)5Cl4]2·(C48H48N32O16)3·35H2O (a = 21.038(3) Å; α = 61.20(1)°, V = 6762.0(14) Å3, space group R
, Z = 1, ρ(calc) = 1.582 g/cm3). The [Mo3S4(H2O)3Cl6]2− anion complex was isolated as three geometrical isomers.Original Russian Text Copyright © 2004 by E. V. Chubarova, D. G. Samsonenko, H. G. Platas, F. M. Dolgushin, A. V. Gerasimenko, M. N. Sokolov, Z. A. Starikova, M. Yu. Antipin, and V. P. Fedin__________Translated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 6, pp. 1049–1058, November–December, 2004. 相似文献
104.
《Chemphyschem》2002,3(12):1024-1030
N,N,N‐butylethylpentylpropylammonium iodide 4 and related molecules have been selectively synthesised from commercially available aldehydes, amines and alkyl iodides using a reductive alkylation procedure. The crystalline texture of 4 obtained on cooling is optically isotropic between crossed polarisers, indicating a cubic structure. Differential scanning calorimetry (DSC, +10 K min?1) reveals a glass phase transition at ?59 °C and a melting point at 192 °C. The melting entropy (23.9 J mol?1 K?1) indicates a first‐order transition between a highly disordered mesophase and the isotropic liquid. Powder X‐ray diffraction patterns were indexed in the cubic system (a=14.08Å; Pm n space group). In this cell, the molecular packing with Z=6 corresponds to a rather low compactness of 65 %. Iodine and tetraalkylammonium ions occupy positions with a m2 site symmetry. These highly symmetrical states may be generated by stepwise rotation of the ammonium cation. The same structural model for orientationally disordered crystal (ODIC) phases can be applied to a series of tetraalkylammonium bromides and iodides. 相似文献
105.
A. N. Chekhlov 《Journal of Structural Chemistry》2005,46(1):182-184
The crystal and molecular structure of tris(m-chlorophenyl)phosphine selenide, C18H12Cl3PSe (I), was investigated by X-ray diffraction (XRD) analysis. The trigonal rhombohedral structure of I (space group \(R\overline 3 c\), a = 14.110(2) Å, c = 32.360(4) Å, Z = 12) was solved by direct methods and refined by least squares in an anisotropic approximation (R = 0.029) for 1319 averaged measured reflections (CAD-4 automatic diffractometer, λCuKα). 相似文献
106.
A polyphosphide of the type (NaP)X 1 was obtained from red phosphorus and sodium in presence of small amounts of naphthalene in 1,2-dimethoxyethane as solvent. 1 reacts with alkyl halides in dependence on the kind of alkyl group with formation of different alkylcyclophosphanes. As definite compounds Me5P5 2 , Et5P5 3 (with not definite constitution), i-Pr4P4 4 and t-Bu4P4 5 could be isolated. 1 was identified by X-ray diffraction, 2 – 5 by means of their 1H, 13C, 31P n.m.r. and mass spectra. The molecular structure of 4 was identified by electron diffraction. 相似文献
107.
Crystals of Ba5Fe5−xPtxClO13 and Ba5Co5−yPtyClO13 were prepared for x=1.31, 1.51, 1.57, 1.59 and y=0, 0.97 and 1.08 in a BaCl2 flux and investigated by X-ray diffraction methods. These compounds adopt a 10H perovskite structure built from the stacking of BaO3 and BaOCl layers in the sequence (BaO3)4(BaOCl) with space group P63/mmc. The cation sites within the trimeric unit of face-sharing octahedra are occupied by Co or Fe and Pt ions, while the tetrahedral sites formed between BaO3 and BaOCl layers are only occupied by Fe or Co. Moreover, oxygen stoichiometry indicates an average oxidation state for Co and Fe higher than +III, indicating the stabilization of Co4+ and Fe4+. 相似文献
108.
The structural and magnetic properties of a new ternary Ir-Mn-Ge phase, Mn3IrGe, as well as the solid solution Mn3Ir(Si1−xGex), 0?x?1, have been investigated by means of X-ray and neutron powder diffraction, magnetization measurements and first principles calculations. The crystal structure is cubic, of the AlAu4-type (an ordered form of the β-Mn structure), Z=4, space group P213, and the unit-cell dimension varies linearly with the silicon content. For all compositions, antiferromagnetic ordering is found below a critical temperature of about 225 K. The magnetic structure is noncollinear, as a result of frustrated magnetic interactions on a triangular network of Mn atoms, on which the moments rotate 120° around the triangle axes. The magnitude of the magnetic moment at 10 K is 3.39(4) μB for Mn3IrGe. The theoretical calculations reproduce with very good accuracy the magnitudes as well as the directions of the experimentally observed magnetic moments. 相似文献
109.
Khafizova L. O. Ibragimov A. G. Yalalova D. F. Borisova A. L. Khalilov L. M. Dzhemilev U. M. 《Russian Chemical Bulletin》2003,52(9):2012-2016
A method for the synthesis of secondary and tertiary alcohols was developed. The method is based on cycloalumination of olefins with trialkylalanes in the presence of Zr-containing catalysts followed by the CuCl-catalyzed in situ reaction of the corresponding aluminacyclopentanes with aldehydes or ketones. 相似文献
110.
Bagiyan G. A. Koroleva I. K. Soroka N. V. Ufimtsev A. V. 《Russian Chemical Bulletin》2003,52(5):1135-1141
Side self-oxidation of thiols was studied. It was found that these reactions in neutral and alkaline solutions are induced by impurities of variable-valence metals. The ability of transition metals to catalyze oxidation of thiols changes in the order Cu > Mn > Fe > Ni Co. The plot of the self-oxidation rate vs. pH passes through a maximum whose position on the pH scale depends on both the nature of metal and the structure of the thiol oxidized. For thiols having different structures, the kinetic orders in reactions catalyzed by copper ions differently vary with pH, which is apparently associated with the formation of complexes possessing different catalytic activity. 相似文献