共查询到20条相似文献,搜索用时 10 毫秒
1.
Abderrahim Guelylah Gotzon Madariaga 《Acta Crystallographica. Section C, Structural Chemistry》2003,59(5):i32-i34
The structure of Rb2Cd2(SO4)3 at room temperature has been refined using X‐ray diffraction data. The structure is similar to that of other cubic langbeinites. However, the title compound differs from other type I langbeinites in that the bond‐valence sums of the metal cations (in particular the Rb atoms) are practically equal to their nominal chemical valences. 相似文献
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Ali Boudjada Olivier Hernandez Jean Meinnel Mohammed Mani Werner Paulus 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(9):1106-1108
In the structure of triiodomesitylene (1,3,5‐triiodo‐2,4,6‐trimethylbenzene), C9H9I3, at 293 K, the benzene ring is found to be significantly distorted from ideal D6h symmetry; the average endocyclic angles facing the I atoms and the methyl groups are 123.8 (3) and 116.2 (3)°, respectively. The angle between the normal to the molecular plane and the normal to the (100) plane is 5.1°. No disorder was detected at 293 K. The thermal motion was investigated by a rigid‐body motion tensor analysis. Intra‐ and intermolecular contacts are described and topological differences compared with the isomorphous compounds trichloromesitylene and tribromomesitylene are discussed. 相似文献
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Berislav Peri Biserka Koji‐Prodi 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(2):211-212
The structure of 4,4′‐dibromobenzophenone, C13H8Br2O, was determined at two different temperatures (293 and 103 K). A phase transition was not detected in this temperature range. Its crystal structure was found to be isostructural with that of the diiodo analogue, but not with the structure of the dichloro derivative. 相似文献
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《Angewandte Chemie (International ed. in English)》2015,54(35):10066-10067
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Dmitry Yu. Naumov Dmitrii S. Yufit Elena V. Boldyreva Judith A. K. Howard 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(7):790-792
The crystal structure of poly[copper(II)‐di‐μ‐hypophosphito‐μ‐urea], [Cu(H2PO2)2(CH4N2O)]n, has been determined at 293, 100 and 15 K. The geometry of the hypophosphite anion is very close to ideal, with point symmetry mm2. Each Cu atom lies on an inversion centre and is coordinated to six O atoms from four hypophosphite anions and two urea molecules, forming a tetragonal bipyramid. The unique urea molecule lies on a twofold axis. Each hypophosphite anion in the structure is coordinated to two Cu atoms. The hypophosphite anions, urea molecules and CuII cations form polymeric ribbons. The CuII cations in the ribbon are linked together by two hypophosphite anions and a urea molecule, which is coordinated to Cu via an O atom. The ribbons are linked to each other by N—H?O hydrogen bonds and form polymeric layers. 相似文献
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Brian N. Figgis Alexandre N. Sobolev 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(8):885-886
The crystal structure of trisodium hexanitrocobaltate(III) has been determined by X‐ray diffraction at 293 and 10 K. It contains the slightly distorted octahedral Co(NO2)63? anion. 相似文献
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Brian N. Figgis Alexandre N. Sobolev Edward S. Kucharski Vanessa Broughton 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(6):e228-e229
The crystal structure of tripotassium sodium hexachloroferrate(II) has been determined by X‐ray diffraction at 293, 84 and 9.5 K. The accurate and extensive data sets collected should be suitable for charge–density analysis studies. 相似文献
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George Ferguson Christopher Glidewell John Nicolson Low James L Wardell 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(6):692-694
The title compound, C14H14O2S2, contains discrete molecules and is a polymorph of a structure reported previously by Caputo, Palumbo, Nardelli & Pelizzi [Gazz. Chim. Ital. (1984), 114 , 421–430]. The present structure contains no intermolecular C—H?O hydrogen bonds, whereas in the previous polymorph, the molecules are linked into continuous chains by such interactions. 相似文献
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Brian N. Figgis Alexandre N. Sobolev Edward S. Kucharski Vanessa Broughton 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(7):735-737
The crystal structure of dicaesium potassium hexacyanomanganese(III) has been determined by X‐ray diffraction at 293, 85 and 10 K. The Mn and K atoms lie on inversion centres and the Cs atom is in a general position. The accurate and extensive data sets collected should be suitable for charge–density analysis studies. 相似文献
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Gilles Olive Dianne D. Ellis Didier Siri Franois Le Moigne Martin Lutz Anthony L. Spek Paul Tordo Jean‐Pierre Reboul 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(6):720-722
The title compound, C4H11NO6P2, reveals a two‐dimensional network of P—O—H?O=P and N—H?O=P hydrogen‐bond interactions, forming molecular slabs parallel with the (010) plane. One O—H?O interaction is distinct within these sets: whilst forming the shortest intermolecular hydrogen bond, it possesses a short P—O(H) bond of 1.5291 (10) Å. Weak C—H?O contacts link individual stacks to produce a three‐dimensional array. The compound is zwitterionic: one H atom from a P—O—H group has transferred to the pyrrolidine ring N atom. 相似文献
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Alicja Janik Anna Chyra Katarzyna Stadnicka 《Acta Crystallographica. Section C, Structural Chemistry》2007,63(10):o572-o575
The crystal structure of a protected l ‐tyrosine, namely N‐acetyl‐l ‐tyrosine methyl ester monohydrate, C12H15NO4·H2O, was determined at both 293 (2) and 123 (2) K. The structure exhibits a network of O—H...O and N—H...O hydrogen bonds, in which the water molecule plays a crucial role as an acceptor of one and a donor of two hydrogen bonds. Molecules of water and of the protected l ‐tyrosine form hydrogen‐bonded layers perpendicular to [001]. C—H...π interactions are observed in the hydrophobic regions of the structure. The structure is similar to that of N‐acetyl‐l ‐tyrosine ethyl ester monohydrate [Soriano‐García (1993). Acta Cryst. C 49 , 96–97]. 相似文献
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《Acta Crystallographica. Section C, Structural Chemistry》2017,73(11):937-940
Adiponitrile, C6H8N2, is a key intermediate in the synthesis of the polyamide Nylon 66 and is produced industrially on a large scale. We have determined the crystal and molecular structure of adiponitrile by single‐crystal X‐ray analysis at 100 K, a suitable crystal (m.p. 275 K) having been grown from the melt at low temperature. The compound crystallizes in the monoclinic space group P 21/c with Z = 2. In the crystal structure, the molecule adopts an exact Ci‐symmetric gauche –anti –gauche conformation of the C—C—C—C skeleton about an inversion centre. The molecules are densely packed, with short intermolecular contacts between the α‐H and nitrile N atoms. 相似文献
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Anna Michta Elbieta Chemecka Maria Nowak Joachim Kusz 《Acta Crystallographica. Section C, Structural Chemistry》2008,64(8):o411-o413
The title compound, C8H9NS, has four symmetry‐independent molecules in the asymmetric unit. These molecules link into two independent infinite N—H...S hydrogen‐bonded chains in the a‐axis direction with graph‐set notation C22(8). The NH—CS group adopts a trans conformation and forms a dihedral angle of about 50° with the phenyl ring. The intermolecular hydrogen‐bond energy calculated by the density functional theory (DFT) method is −14.95 kJ mol−1. The correlation between the IR spectrum of this compound and the hydrogen‐bond energy is also discussed. This molecular system is of interest because of its biological function. 相似文献
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Rüdiger W. Seidel Richard Goddard 《Acta Crystallographica. Section C, Structural Chemistry》2015,71(8):664-666
The simplest alkyl aryl ether, anisole (methoxybenzene), C7H8O, is a feedstock chemical and is widely used in the pharmaceutical industry. The structure of anisole at 100 K, as determined by single‐crystal X‐ray analysis, is reported. A crystal (m.p. 236 K) suitable for X‐ray diffraction was obtained from the melt. The title compound crystallizes in the centrosymmetric space group P21/c with two molecules in the asymmetric unit (Z′ = 2). Both crystallographically distinct molecules adopt a virtually flat (Cs‐symmetric) conformation. The arrangement of the molecules in the solid state appears to be governed by close packing. No face‐to‐face π–π stacking of the molecules is observed, but rather edge‐to‐face interactions result in a herringbone packing motif. 相似文献
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Shao‐Fang Lu Zi‐Xiang Huang Jin‐Ling Huang 《Acta Crystallographica. Section C, Structural Chemistry》2006,62(9):i73-i75
The single‐crystal X‐ray diffraction structure analysis of an excellent non‐linear optical material, viz. II‐BaB2O4 or Ba3(B3O6)2, has been carried out at 163 and 293 K. The two sets of structural data are compared and indicate a significant shortening of the c axial length in the unit cell at 163 K, whereas the a and b axial lengths essentially do not change. 相似文献
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Rüdiger W. Seidel Richard Goddard Nils Nthling Christian W. Lehmann 《Acta Crystallographica. Section C, Structural Chemistry》2016,72(10):753-757
Acetic anhydride (ethanoic anhydride), (CH3CO)2O, is a widely used acetylation reagent in organic synthesis. The crystal and molecular structure, as determined by single‐crystal X‐ray analysis at 100 K, is reported for the first time. A crystal of the title compound (m.p. 200 K) suitable for X‐ray diffraction was grown from the melt at low temperature. The title compound crystallizes in the orthorhombic space group Pbcn, with Z = 4. In the crystal, the molecule adopts an exact C2‐symmetric conformation about a crystallographic twofold axis. The molecules are densely packed. Two of the methyl H atoms form short intermolecular contacts to a neighbouring carbonyl O atom, which can be viewed as weak hydrogen bonds. 相似文献
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