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1.
Tetramethylammonium sodalite, a synthetic species of composition (CH3)4NAlSi5O12, has been obtained in good yield under hydrothermal conditions in the absence of metal cations. Its crystal structure has been determined using accurate powder data since single crystals could not be grown. The structure seems to be body-centered cubic with a = 8.975 Å but the true symmetry is non-cubic (probable space group I4 ). Each cage of the aluminosilicate framework contains one tetramethylammonium ion. The organic cation does not conform to the cubic symmetry of the ideal framework. The methyl groups point to oxygen atoms of the framework, and the short methyl-oxygen distances of 3.06 Å indicate strong C? H … O interaction. The present results indicate beyond doubt that C? H … O hydrogen bonding involving methyl groups can occur in silicates. This is of particular significance in zeolite chemistry and in the interpretation of interlayer distances in organic clay complexes. 相似文献
2.
Synthesis and Crystal Structure of HfOS On attempts to prepare binary and ternary hafnium sulfides a small quantity of single crystals was obtained which could be identified as HfOS. The new compound is cubic, space group P213 with a = 5.6824(6) Å. It is isostructural with the cubic form o ZrOS. In order to refine the structure parameters intensity measurements were carried out by means of a four-circle single crystal diffractometer. 相似文献
3.
Synthesis and Crystal Structure of KMnP and KMnAs KMnP and KMnAs have been prepared from the elements at 800-°C in a closed system. X-ray investigations suggest a layer-type structure where the manganese atoms are tetrahedrally coordinated by the phosphorus or arsenic atoms. The coordination polyhedra share common edges in two dimensions. The compounds crystallize in the space group P4/nmm with a = 4.275, c = 7.668 Å for KMnP and a = 4.391, c = 7.791 Å for KMnAs, respectively; z = 2. The structural relations to the ternary arsenides with transition metals and lithium, t o Mn2As, to the oxidehalides of the lanthanides and to ternary sulfides are discussed. 相似文献
4.
W. E. Schklower Yu. T. Strutschkow L. E. Guselnikow W. W. Wolkowa W. G. Awakyan 《无机化学与普通化学杂志》1983,501(6):153-156
Molecular and Crystal Structure of Tetramethylcyclodisilthiane The molecular and crystal structure of the title compound (I) has been determined by X-ray diffraction. The Si2S2-tetracycle is planar with Si? S bond length of 2.152(2) Å and bond angles SiSSi smaller then SSiS (82.46(6) and 97.54(7)°). 相似文献
5.
Synthesis and X-Ray Structure Determination of N-Formylformamidinium Hexachloroantimonate The title compound is formed in high yields by the interaction of [Cl2CH? NH? CH?NH2][SbCl6] with SO2 in CH2Cl2 solution. According to the spectra (i.r. and 1H-n.m.r.) the cation [O?CH? NH? CH?NH2]+ exists in an almost planar, all-cisoide conformation. The hexachloroantimonate crystallizes in the orthorhombic space group Pna21 with 4 formula units per cell. The anion-cation cross-linkage by relative short NH…?Cl(Sb) bridges is remarkable. The structure was refined to an R value of 0.027. 相似文献
6.
A new synthetic zeolite, (CH3)4NA1Si3O8, H2O, has been synthesized and shown to be an isotype of the mineral gismondine, CaAl2Si2O8,4H2O. Sodium and other cations can be introduced by ion exchange after thermal decomposition of the organic cation. A continuous structural change to «cubic» NaP has thereby been recorded, which indicates that the latter is also based on a gismondine-type aluminosilicate framework. The crystal structure of tetramethylammonium-gismondine has been determined using X-ray powder data supplemented by electron diffraction. The crystals are tetragonal, a = 9.84 and c = 10.02 Å, with 4 formula units per unit cell. The apparent symmetry of the framework structure is I41/amd, however, this is violated by the organic cation. Two of the methyl groups are pointing to oxygen atoms of the framework and the short methyl-oxygen distances indicate C? H ? O interaction. 相似文献
7.
Preparation and Crystal Structure of CsTe4 CsTe4 results from a melting reaction at 570°C in sealed quartztubes. The starting materials Cs and Te in the molar ratio 1:4 are produced in a first step by controlled decomposition of the CsN3 from mixtures of CsN3 and Te (1:4) at 350°C. CsTe4 is monoclinic, space group P21/c, with a = 7.857(1) Å, b = 7.286(1) Å, c = 14.155(2) Å, β = 93.83(1)°, and Z = 4. The tellurium atoms form a two-dimensional puckered layer built of from pseudo-trigonal-bipyramidal, T-shaped units Te4?. The central tellurium atom of this unit may be considered as a pseudo iodine. The compound is compared with other tellurides MTen having some like that unexpected principles of connection. 相似文献
8.
Synthesis and Crystal Structure of LiHSO4 Single crystals of the new compound LiHSO4 are synthezised from the system Lithiumsulfate/Sulfuric acid. The up to day not determined structure of the title compound is monoclinic, space group P21/c with the lattice constants a = 5.234(2), b = 7.322(1) and c = 8.363(1) Å, b? = 90.02(2)°. The volume of the unit cell has been determined to V = 320.5 Å3, the number of formula units to Z = 4 and the density to Dx = 2.156 g cm?3. There are crystallographically identical SO3(OH)- and LiO4-tetrahedra in the structure. Every tetraheda is linked to four different tetrahedra of the other sort. Two neighboured LiO4 terahedra form a common edge. In that way layers are formed running parallel the yz-plane. These layers are connected over hydrogen bonds. 相似文献
9.
Synthesis and Crystal Structure of KTeOF3 KTeOF3 has been synthesized by solid state reaction of KF, TeO2 and KTeF5 in equimolar amounts. Its crystal structure has been solved by single crystal structure analysis (P42/n, a = 1007.96(3), c = 789.58(3) pm, Z = 8, R1 = 0.0311). As a characteristic feature, the compound contains unprecedented dimeric anions Te2O2F62– formed by two edge‐sharing pseudo‐octahedral units. IR and Raman data are given. 相似文献
10.
Preparation and Crystal Structure of KSbS2 Red KSbS2 was prepared in a aqueous solution of KHS and Sb2S3 under mild hydrothermal conditions. For crystallographic data see ?Inhaltsübersicht”?. There are SbS-chains, built up by ψ-trigonal bipyramids, which are connected by sharing edges. The K+-Ions between these chains have a nearly octaedric coordination. 相似文献
11.
Synthesis and Crystal Structure of CaBiVO5 Single crystals of the hitherto unknown compound CaBiVO5 were prepared and investigated by X-ray work. It crystallizes with orthorhombic symmetry, space group D? Pbca, a = 11.2022, b = 5.4283, c = 15.5605 Å, Z = 8. The crystal structure is characterized by layers of the edge-linked CaO7 polyhedra, isolated VO4 tetrahedra and an asymmetric surrounding of Bi3+ by oxygen. 相似文献
12.
Preparation and Crystal Structure of CsBO2 Colourless single crystals of CsBO2 have been prepared from intimate mixtures of CsO0.57 and B2O3 (Cs:B = 3.2:1.0; 600°C, 38 d). The structure determination from fourcircle diffractometer data (MoK, 443 Io (h k l), R = 3.1%, Rw = 2.0%) confirms the isotypy with NaBO2 and KBO2: space group R 3 c; a = 1 363.7(2) pm, c = 836.5(2) pm; Z = 18. A characteristic structure unit is the planar cyclic anion [B3O6]3?. Effective Coordination Numbers (ECoN), Mean Fictive Ionic Radii (MEFIR), the Madelung Part of Lattice Energy (MAPLE) and the Charge Distribution (CHARDI) are calculated and discussed. 相似文献
13.
Dieter Chales de Beaulieu Hanskarl Müller-Buschbaum 《Monatshefte für Chemie / Chemical Monthly》1982,113(4):415-420
Single crystals of BaVO2,5 were prepared by high temperature LASER-technique under a hydrogen atmosphere. The X-ray investigation leads to a trigonal symmetry (a=571.8;c=1161.3 pm, space group C
3v
1
-P3m 1). BaVO2,5 consists of a closest sphere packing of oxygen with a sequence of cubic and hexagonal layers of the type ... ccchh ... The consequences in respect to the coordination of Ba2+ and V3+ are discussed. 相似文献
14.
Triphenylgallane reacts with alkyl- and aryl-thiols, respectively, with formation of the corresponding diphenylalkyl- and diphenylaryl-thiogallanes. Spectra and some physical and chemical properties of the new compounds are given. The results of the X-ray structure determination of diphenylethylthiogallane are discussed. 相似文献
15.
Synthesis and Crystal Structure of Calcium Imide, CaNH Single-crystals of calcium imide were obtained for the first time by the reaction of a mixture of calcium amide with sodium amide at 850°C in an autoclave for salt melts. After cooling the autoclave to room temperature the crystals are embedded in solid Na which was extracted by liquid ammonia. The structure of calcium imide was determined from single-crystal diffractometer data: space group Fm3 m, Z = 4, a = 5.143(1) Å, R/Rw = 0.032/0.028 mit N(F ? 3σ(F )) = 26, N(Var.) = 5. Ca and N atoms are arranged in the motif of the NaCl structure type. The hydrogen atoms of the imide groups are disordered within the Ca octahedra, and they occupy a six fold split position. 相似文献
16.
The Crystal Structure and Absolute Configuration of Mikrolin. The crystal structure and absolute configuration of mikrolin has been determined by X-ray diffraction. Crystals of mikrolin belong to space group P212121 with a = 17.867, b = 7.947, c = 9.824 Å, Z = 4. The structure was solved by multi-solution method, and refined to R = 0.060. The anomalous scattering of CuKα-radiation by chlorine was used to determine the absolute configuration of the molecule. 相似文献
17.
Preparation and Crystal Structure of Lithiumhydrogensulfide, LiHS Lithiumhydrogensulfide, LiHS, is prepared from lithiumamide, LiNH2, by reaction with liquid hydrogensulfide. At 150°C the solubility of LiHS in H2S is sufficient for the growth of single crystals in a temperature gradient within the autoclaves used. The X-ray structure determination at 295 K is characterized by the following data: Lithium occupies tetrahedral sites in a distorted cubic close-packed arrangement of S; in PtS sulfur occupies tetrahedral sites in a similar way in a distorted close packing of Pt. Hydrogen atoms of the HS??ions are dynamically disordered in a split position linearly bound to S. At 228 K a thermal effect occurs in DSC-measurements indicating that below this temperature the HS??ion has fixed positions. 相似文献
18.
Preparation, Crystal Structure, and Properties of Potassium Hydrogen Cyanamide For the preparation of KHCN2 melamine has been reacted with potassium amide in liquid ammonia. After evaporation of the solvent the resulting solid has been transformed at 210°C. KHCN2 (P212121, a = 708.7(2), b = 909.0(2), c = 901.4(2) pm, Z = 8, R = 0.039, wR = 0.016) is yielded as a coarse crystalline product. In the solid K+ and HCN ions occur. As expected two significantly differing bond-distances C? N (117.3(5) pm) and HN? C (128.7(5) pm) have been found in the anion. According to IR-spectroscopy a non linear group N? C? N (174.4(4)°) is observed. 相似文献
19.
W. E. Oberhnsli 《Helvetica chimica acta》1969,52(7):1905-1911
The crystal structure of the Nb-methobromid of the alcaloid meloscin has been determined by three-dimensional X-ray crystallographic methods. The crystals belong to the orthorhombic space group P212121 with four molecules per unit cell. The cell constants are a = 10.01, b = 17.79, c = 11.43 Å. The absolute configuration has been obtained by the use of anomalous dispersion effects. 相似文献