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1.
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   

2.
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   

3.
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   

4.
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 º 2 ? 3σ(F º 2 )) = 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   

5.
Preparation and Crystal Structure of Cs2Sb4S7 The first thioantimonite of Cesium has been synthesized and its crystal structure determined. The substance crystallizes monoclinic with spacegroup P21/c. The lattice constants are a = 1111.2(5) pm, b = 1227.1(5) pm, c = 1163.7(5) pm and ß = 97.60(5)°. There are four formula units in the unit cell. Sb–S chains are formed by trigonal SbS3 pyramids and ψ-trigonal SbS4 bipyramids.  相似文献   

6.
Preparation and Crystal Structure of Rb2Sb4S7 The first thioantimonite of rubidium has been synthesized and its crystal structure determined. The substance crystallizes triclinic with spacegroup P1 . The lattice constants are a = 968.0(5) pm, b = 1193.4(5) pm, c = 723.1(5) pm, α = 87.68(5)°, β = 101.39(5)° and γ = 102.66(5)°. There are two formula units in the unit cell.  相似文献   

7.
Preparation and Crystal Structure of ZrP2S6 and ThP2S6 The compounds ZrP2S6 ( I ) and ThP2S6 ( II ) are synthesized from the elements at 750–800°C. They are isotypic (P42/m, Z = 2; I : a = 668.2, c = 948.9 pm; II : a = 688.0, c = 990.3 pm) and to be described as M4+(P2S6)4?. The thiohypodiphosphate anion has ideal staggered conformation. The cation is coordinated by a (slightly deformed) 42 m dodecahedron of S atoms. The geometrical details correspond to the most favourable ligand distribution.  相似文献   

8.
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   

9.
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   

10.
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   

11.
On the Preparation and Crystal Structure of Rb2Sb4S7 Rb2Sb4S7 was prepared by methanolothermal reaction of Rb2CO3 with Sb2S3 at a temperature of 140°C. An X-ray structural analysis demonstrated that the compound contains polythioantimonate(III) anions (Sb4S72?)n, for which the basic element is a ψ-trigonal (SbS4)-bipyramid. Edge bridged SbS4 polyhedra build vierer single chains (Sb4S84?)n, which are linked via two symmetry related S atoms with neighbouring chains so that an (Sb4S72?)n sheet is formed.  相似文献   

12.
Preparation, Crystal Structure, and Properties of KLi2As The novel arsenide KLi2As has been synthesized either from the elements or from mixtures of the binary components Li3As and K3As in sealed Nb ampoules at 823 K and 623 K, respectively. It crystallizes in the space group Pmmn (no. 59) with a = 445.8(9); b = 671.5(11); c = 627.0(12) pm and Z = 2 formula units. The metallic reflecting silvercoloured platelets hydrolize rapidly under wet air. The compound (Pearson code oP8) is isopuntal with BaLi2Si and an intermediate between the Li3N and the Na3As type of structure. Potassium is distorted tetrahedrally coordinated by four As atoms (d(K? As) = 355 and 367 pm), arsenic by four potassium and six lithium atoms (d(As? K) = 355–367 pm; d(As? Li) = 260–265 pm) in form of a sphenocorona. Lithium is threefold coordinated (distorted trigonal planar) by arsenic and this unit is enveloped by a monocapped trigonal prism build by three lithium and four potassium atoms.  相似文献   

13.
Preparation and Crystal Structure of a New Isomeric Form of As4S4 As4S4(II) was prepared by melting of the pure elements As and S in the atomic ratio 1:1 at the temperature range 500°–600°C and a quickly cooling to the room temperature. Yellow-orange coloured and very thin platy single crystals were recrystallized from a CS2 solution. The crystal parameters are: a = 11.193, b = 9.994, c = 7.153 Å and β = 92.8°. The space group in P21/n (No. 14). The molecule can be principally deduced from the As4-tetraedron. By the connection of the folded plane SAs3 to the platy pyramide S3As the cage structure of the As4S4(II) molecule will be built.  相似文献   

14.
Preparation and Crystal Structure of Cu2SrSnS4 Cu2SrSnS4 was prepared from a mixture of the three binary sulfides at 620-700° C. The structure analyses by single crystal X-ray investigations yields a trigonal C-symmetrie for the unit of the structure with a = 6.290 and c = 15.578 Å and three formula units. Space group: C–P31 (No. 144). Copper and tin have tetrahedral surrounding of S2?. The neighbourhood of Sr2+ has the shape of a deformed archimedic antiprisma.  相似文献   

15.
Synthese and Crystal Structure of Ag2MnO4 Single crystals of Ag2MnO4 have been grown from aqueous solution. The crystal structure has been solved and refined using diffractometer data (Pnma, a = 999.8(2); b = 698.9(1); c = 547.4(2) pm). The mean bond-length Mn? O within the tetrahedral anions is 167.9 pm. In spite of similar lattice constants and identical space group, Ag2MnO4 is not isostructural to Olivine. The structural differences are discussed.  相似文献   

16.
Synthesis and Crystal Structure of NaBi2AuO5 NaBi2AuO5 was obtained by hydrothermal reaction of ‘Bi2O5’, Au2O3 · 2H2O and saturated aqueous NaOH solution at temperatures from 300 to 600°C and oxygen pressure from 3 × 108 to 6 × 108 Pa for the first time. The crystal structure (P4 b2; a = 1 220.02(6) pm; b = 386.68(3) pm; Z = 4; Rw = 0.022) consists of bisphenoidic distorted AuO4 groups, which are stacked in c-direction. They are connected by square pyramidal BiO5 units. Sodium is occupying holes within the Au/Bi/O framework thus formed.  相似文献   

17.
Preparation and Crystal Structure of Cs4SnO3 Crystals of Cs4SnO3 were synthesized by reaction of SnO with elemental Cs. The compound crystallizes with the triclinic spacegroup P1 with lattice constants a = 737.61(9) pm, b = 1171.3(1) pm, c = 1199.2(1) pm, α = 66.08(3)°, β = 80.88(2)°, γ = 82.28(3)° and Z = 4. The crystal structure exhibits isolated stannate(II) ions [SnIIO3]4– of ψ-tetrahedral form. Whereas a new structure type is present, there is a close relationship with the structures of the Cs stanntates and plumbates(IV).  相似文献   

18.
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   

19.
Synthesis, Crystal Structure and Properties of Cesium Ozonide By reaction between CsO2 and mixtures of O2 and O3 in the temperature range from 25°C to ?70°C and subsequent extraction with liquid ammonia pure CsO3 was obtained in grammeamounts. By X-ray powder and thermal techniques a reversible, structural phase transition was detected at +8°C, and decomposition into CsO2 and O2 at +53°C. The low-temperature form (T? CsO3) is isostructural to RbO3 (P21/c; a = 675.1(2), c = 901.5(3) pm, β = 120.74(3)°l Z = 4), the crystal structure of H? CsO3, which shows orientational disorder with respect to the ozonide ion, corresponds to the CsCl-type of structure (a = 436.06(3) pm). Using the geometry as determined for KO3 and RbO3, and the vibrational frequencies of different isotopomeres, the force constants of O3? have been redetermined.  相似文献   

20.
Preparation and Crystal Structure of Rubidium Triiodoplumbate(II) RbPbJ3 crystallizes in the orthorhombic space group Pnam(D) (lattice parameters see above); it is isomorphous with CsPbJ3. The crystal structure has been determined from 1452 independent reflexes by Patterson- and Fourier-syntheses and refined three dimensionally by least-squares-methods. 6 I surround Pb nearly octahedrally. The octahedra are arranged in the form of double chains along the c-axis, which are held together by Rb. (Pb? I bond distances see above). The “inert 6s-pair” at Pb is stereochemically inactive.  相似文献   

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