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1.
Nitrido-silicates. III [1] High-Temperature Synthesis, Crystal Structure, and Magnetic Properties of Ce3[Si6N11] Pure Ce3[Si6N11] was obtained as transparent yellow crystals by reaction of metallic cerium with silicon diimide (Ce:Si = 1:2) under nitrogen atmosphere in a specially developed high-frequency furnace at 1660°C. Ce3[Si6N11] (P4bm, a = 1013.7(3), c = 483.9(5) pm, Z = 2, R = 0.034, wR = 0.024) contains Ce3+ ions as well as a three-dimensional covalent anionic network structure of corner-sharing SiN4 tetrahedra. Measurements of the magnetic susceptibility gave no indications for magnetic ordering phenomena in the temperature range between 2 and 300 K. Above 100 K pure Curie-Weiss behaviour (μeff = 2,10 μB, determined at room temperature) was observed.  相似文献   

2.
Nitrido-Silicates. II. High Temperature Syntheses and Crystal Structures of Sr2Si5N8 and Ba2Si5N8 Pure Sr2Si5N8 and Ba2Si5N8 were obtained by reaction of silicon diimide with metallic strontium and barium, respectively. The reactions have been carried out under nitrogen atmosphere in a specially developed high-frequency furnace at temperatures between 1 550 and 1 650°C. Sr2Si5N8 (Pmn21, a = 571.0(2), b = 682.2(2), c = 934.1(2) pm, Z = 2, R = 0.037, wR = 0.021) and Ba2Si5N8 (Pmn21, a = 578.3(2), b = 695.9(2), c = 939.1(2) pm, Z = 2, R = 0.022, wR = 0.018) are isotypic and contain M2+ ions as well as a three-dimensional covalent network structure of corner-sharing SiN4 tetrahedra. Two sorts of N occur with molar ratio 1 : 1 which are bonded to two and three Si, respectively. Predominantly, the N which are bonded to two Si belong to the coordination spheres of the M2+ ions.  相似文献   

3.
Synthesis and Crystal Structure of Sodium Tetraoxo Nitrido Tungstate(VI), Na5WO4N Colourless crystals of Na5WO4N are obtained besides Na4WO2N2 [1] by the reaction of WO3 with NaNH2 (15:1) at 350°C ≥ T ≥ 750°C in autoclaves to prevent early decomposition of sodium amide. X-ray single crystal investigations are characterized by the following data:
  • Na5WO4N: Cmc21 (No. 36), Z = 4
  • a = 9.873(2) Å, b = 5.769(1) Å, c = 10.648(2) Å
  • Z(F)≥ 3σ(F) = 2182, Z(Var.) = 55, R/Rw = 0.029/0.039
The structure contains the tetragonal pyramidal ion WO4N5? with nitrogen at the apex connected via Na+ ions irregularly coordinated by one nitrogen and four oxygen atoms of different anions.  相似文献   

4.
Synthesis and Crystal Structure of Rb8[P4N6(NH)4](NH2)2 with the Adamantane-like Anion [P4N6(NH)4]6? RbNH2 reacts with P3N5 (molar ratio 6:1) at 400°C within 5 d to colourless Rb8[P4N6(NH)4](NH2)2. Suitable crystals for a X-ray structure determination were obtained: The compound contains adamantane-like molecular anions [P4N6(NH)4]6?. Their centres of gravity are arranged in a distorted hexagonal primitive array. All trigonal prisms of this array contain one amide ion. Rubidium ions connect the anions irregularly.  相似文献   

5.
Nitrido Sodalites. I Synthesis, Crystal Structure, and Properties of Zn7–xH2x [P12N24]Cl2 with 0 ? x ? 3 The nitrido sodalites Zn7–xH2x[P12N24]Cl2 with 0 ? x ? 3 are obtained by heterogeneous pressure-ammonolysis of P3N5 at presence of ZnCl2 (T = 650°C). These compounds are available too by reaction of ZnCl2, (PNCl2)3, and NH4Cl at 700°C. The crystal structures of four representatives of the above mentioned compounds have been refined by the Rietveld full-profile technique using X-ray powder diffractometer data (I4 3m, a = 821.61(4) to 824.21(1) pm, Z = 1). In the solid a three-dimensional framework of corner-sharing PN4-tetrahedra occurs (P? N: 163.6 pm, P? N? P: 125.6°, mean values) which is isosteric with the sodalite type of structure. In the center of the β-cages Cl? ions have been found, which are tetrahedrally coordinated by Zn2+ ions. The Zn2+ ions are statistically disordered. According to the phase-width observed (0 ? x ? 3) the Zn2+ ions may be partially replaced each by two hydrogen atoms which on the other hand are covalently bonded to nitrogen atoms of the P? N framework. The IR-spectra of these compounds show characteristic vibrations.  相似文献   

6.
Synthesis and Crystal Structure of [Li(DME)2I] . LiI can be dissolved at 50°C in toluene/DME (2:1). At - 20°C [Li(DME)2I] ( 1 ) was isolated in 75% yield. 1 was characterized by NMR techniques as well as an X-Ray structure determination. 1 crystallizes in the space group C2/c with a = 1 356.9(2), b = 813.2(1), c = 1 259.1(2) pm, and β = 99.74(1)°.  相似文献   

7.
Nitride Sulfide Chlorides of the Lanthanides. III. Synthesis and Crystal Structure of Pr5N3S2Cl2 By reacting praseodymium with sulfur, sodium azide and praseodymium trichloride in sealed, evacuated silica tubes (850°C, 7 d), the nitride sulfide chloride Pr5N3S2Cl2 is obtained in case of a 4:2:1:1 molar ratio of the reactants (Pr:S:NaN3:PrCl3). A slight excess of trichloride or the addition of NaCl as a flux supports the yield of brownish red, rod-shaped transparent crystals which prove to be stable against hydrolysis. The crystal structure (monoclinic, C2/m (no. 12), a = 1540.2(1), b = 400.92(3), c = 1656.3(1) pm, β = 101.24(1)°, Z = 4, R = 0.039, Rw = 0.028) was determined by means of X-ray single crystal data. Thus five crystallographically different cations (Pr3+) are present which with three distinct kinds of nitride anions (N3?) build up two types of translationally commensurate chains from interconnected [NPr4] tetrahedra. With an additional edge per “chain-link” in chain I, two single chains [NPr3/3ePr1/1t]3+ (?[NPr2]3+) of cis-edge connected [NPr4] tetrahedra (known from the Sm4N2S3-type structure) are condensed into the double chain [(N1){(Pr1)(2+2)/(2+2)e,e(Pr2)(2+1)/(2+1)e,v}(N2)(Pr3)1/1t]3+ (?[N2Pr3]3+). Chain II consists of two single chains [NPr2/2vPr2/1t] 6+ (?[NPr3]6+) of vertex-connected [NPr4] tetrahedra (known from the Sm3NS3-type structure), which are condensed to the double chain [(N3)(Pr4)2/2e(Pr5)2/2v]3+ (?[NPr2]3+) via an additional edge per “chain-link” too. Both types of chains are bundled along [010] like a closest packing of rods. Four crystallographically different but by X-ray diffraction indistinguishable anions S2? and Cl? hold both cationic double chains together and also adjust the charge balance in a molar ratio of 1 : 1.  相似文献   

8.
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   

9.
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   

10.
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   

11.
A Contribution on the Crystal Structure of CuYW2O8, CuHoW2O8, and CuYW2O8 Single crystals of (I) CuY2O8, (II), CuHoW2O8, and (III) CuYbW2O8 were prepared and investigated by X-ray technique. (I) crystallizes with triclinic symmetry, space group C? P1 (a = 5.939 Å, b = 6.042 Å, c = 5.025 Å; α = 112.30°, β = 111.77°; Z = 1). (II) and (III) belong to monoclinic symmetry, space group C? P2/n (II) (a = 10.045 Å, b = 5.808 Å, c = 5.021 Å; β = 94.38°; z = 2 (III) a = 9.948 Å, b = 5.824 Å, c = 5.008 Å; β = 93.36°; Z = 2). The crystal structures will be discussed with respect to other to copper rare earth tungstates.  相似文献   

12.
Mixed-ligand Complexes of Technetium. XV. The Reaction of [TcNCl2(Me2PhP)3] with Dialkyldithiocarbamates and N,N-Dialkylthio-carbamoylbenzamidines [TcN(Cl)(Me2PhP)2(Et2dtc)], [TcN(Me2PhP)(Et2dtc)2], and [TcN(Et2dtc)2] can be prepared by stepwise ligand exchange reactions starting from dichlorotris(dimethylphenylphosphine)nitridotechnetium(V), [TcNCl2(Me2PhP)3], and diethyldithiocarbamate. In contrast to this, only one intermediate, [TcN(Cl)(Me2PhP)2(HEt2tcb)], could be isolated during the reaction with N,N-Diethlthiocarbamoylbenzamidine, which yields the bis chelate [TcN(HEt2tcb)2]. [TcN(Me2PhP)(Et2dtc)2] crystallizes in the monoclinic space group P21/c; a = 17.369(5) Å, b = 15.024(1) Å, c = 9.906(3) Å, β = 76.47(1)º, Z = 4. The phosphine is coordinated equatorially. The multiply bonded nitrogen ligand (Tc? N(1) 1.624(3) Å) strongly labilizes the trans positioned donor atom (distance Tc? S(4) 2.826(1) Å). [TcN(HEt2tcb)2] crystallizes in the triclinic space group P1 with a = 9.749(4) Å, b = 11.264(4) Å, c = 12.359(4) Å, α = 75.34(2)º, β = 79.69(2)º, γ = 87.55(2)º, Z = 2. The metal is five-coordinate with the nitrido donor atom occupying the apex of a square pyramid. It's basal plane is formed by the cis-coordinated chelate ligands. The technetium is situated over the basal plane by about 0.6 Å. The Tc?N distane was found to be 1.610(5) Å.  相似文献   

13.
On the Crystal Structure of Ca2PbO4 Single crystals of Ca2PbO4 were prepared by flux technique and investigated by X-ray methods. It crystallizes with orthorhombic symmetry, space group D-Pbam. (a = 5.832; b = 9.766; c = 3.375 Å, Z = 2.) Ca2PbO4 belongs to the Sr2PbO4 type. It shows Ca2+ in a seven fold and Pb4+ in octahedral coordination.  相似文献   

14.
Synthesis and Crystal Structure of (PPh4)2Se6 (PPh4)2Se6 has been prepared by the reaction of selenium with K2Se2 in dimethylformamide solution in the presence of K3[Mn(CN)6] and PPh4Br, forming black crystal needles. According to the crystal structure determination the compound consists of PPh+4 ions and chainlike hexaselenide ions. Space group P6 , Z = 2,4683 Observed unique reflections, R = 0.066. Lattice dimensions at ?90°C: a = 951.0, b = 1094.8, c = 2137.4 pm, α = 82.66°, β = 83.36°, γ = 89.96°.  相似文献   

15.
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   

16.
Synthesis and Crystal Structure of Cu2PtIIPt S8 (NH4)2PtCl6 and Cu(CH3COO)2 were reacted at 380 K in a constant flow of H2S in the molar ratio of 2:1. Subsequent annealing of the product in sealed quartz glass ampoules in the presence of CuS as a buffer for the sulfur activity (temperature range 770 to 870 K) yields Cu2Pt4S8 as a polycrystalline, greyish black powder. Cu2Pt4S8 crystallizes in the space group P2/n (No. 13) with the cell parameters a = 10.6478(2), b = 6.9350(1), c = 6.7411(1) Å, β = 91.942(1), Z = 2. The structure determination and refinement were performed by the means of x-ray powder diffraction data of this first copperthioplatinate. There are no isotypic compounds known, so far. According to the characteristic coordination of the metals by sulfur, the oxidation states are Cu+I, Pt+II and Pt+IV, the compound may be formulated as Cu2Pt+IIPtS8. Cu2Pt4S8 exhibits diamagnetic and semiconducting properties.  相似文献   

17.
Synthesis and Crystal Structure Determination of LiAl[(P2O6)2] Single crystals of previously unknown LiAl[(P2O6)2] have been obtained by reaction of Li2CO3, Al2O3 and H3PO4 (1:1:16) at 350°C. The title compound crystallizes in Pbcn (a = 1 244.54(1), b = 823.40(1), c = 892.46(1) pm; Z = 4). The least-squares refinement (with anisotropic temperature factors) was performed using 766 observed reflections yielding R = 0.029 and R(w) = 0.075. Four anion chains are running parallel to the shortest axis in the unit cell, the period of identity amounting to four. Aluminium is surrounded by an almost regular octahedron, lithium by a distorted tetrahedron of oxygen.  相似文献   

18.
Mercury Compounds with Cyancarbanions. I . Synthesis and Crystal Structure of Dimercury(I)-bis(tricyanmethanide ) With the triclinic unit cell, space group P1 , with the lattice constants a = 5.2794(1) Å, b = 9.9279(1) Å, c = 11.3376(2) Å, α = 71.004(4)°, β = 76.459(2)° and γ = 74.601(4)° are two formula units. The three-dimensional network, which characterizes the structure, results from dimercury(I) ions with sp3 hybridization, which form beside the homonuclear metal bonding three covalent bonds to cyanonitrogen atoms. The tricyanmethanide ion acts by losing symmetry as a tridentate ligand.  相似文献   

19.
Synthesis and Crystal Structure of Cs8P8O24 · 8H2O Cs8P8O24 · 8H2O was obtained from Na8P8O24 · 6H2O by cation exchange. Crystal growth was achieved by applying gel techniques (agar agar). The crystal structure (P1 ; a = 766.6(8); b = 1 156.9(9); c = 1 163.4(9) pm; α = 100,2(1)°; β = 106.5(2)°; γ = 92.2(1)°; Z = 1; 4 099 unique diffractometer data; R = 0.051; R(w) = 0.037) contains cyclo-octaphosphate anions with point symmetry C2h. The cesium atoms are coordinated irregularily by eight and ten oxygen atoms, respectively. The threedimensional linkage of the P8O248?-rings is established via bonds to cesium atoms and hydrogen bonds Provided by H2O molecules.  相似文献   

20.
Synthesis and Crystal Structure of Na10[P4(NH)6N4](NH2)6(NH3)0.5 with an Adamantane-like Anion [P4(NH)6N4]4? Crystals of Na10[P4(NH)6N4](NH2)6(NH3)0.5 were obtained by the reaction of P3N5 with NaNH2 (molar ratio 1:20) within 5 d at 600°C in autoclaves. The following data characterize X-ray investigations: Fm3 m, Z = 8, a = 15.423(2) Å, Z(F) = 261 with F ≥ 3 σ(F) Z(Variables) = 27, R/Rw = 0.086/0.089 The compound contains the hitherto unknown anion [P4(NH)6N4]4?, which resembles adamantane. The total structure can be described as follows: The centers of gravity of units of [Na8(NH2)6(NH3)]2+ – 8Na+ on the corners of a cube, 6NH2? on the ones of an inscribed octahedron with NH3 in the center – follow the motif of a cubic-closest packed arrangement. Units of [Na12(NH2)6]6+ – 12Na+ on the corners of a cuboctahedron and 6NH2? on the ones of an inscribed octahedron – occupy all octahedral and those of [P4(NH)6N4]4? all tetrahedral sites.  相似文献   

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