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1.
Crystal Structure of Sodium Oxide Sulfate Na6O(SO4)2 was prepared from a mixture of Na2O and Na2SO4 by solid state reaction at 500 °C in silver crucibles. Its crystal structure (Fm 3 m, a = 967.7(1) pm, Z = 4, R1 = 0.060, wR2 = 0.1364) can be derived from the fluorite type of structure and corresponds to the anti‐Pentlandite type.  相似文献   

2.
On the Crystal Structure of CaFeF5 Single crystals of CaFeF5 were obtained by heating a mixture of the component fluorides at 860°C for 12 d (a = 549.2(1), b = 1007.6(2), c = 759.9(2) pm, β = 110.02(3)°; space group P21/c, Z = 4). The X‐ray structure redetermination of a twinned specimen confirmed the chain structure of octahedra sharing trans corners already known. But the anomalies reported earlier were removed and less distorted [FeF6] octahedra and [CaF7] pentagonal bipyramids were found, the distances of which are split within the usual range around mean values of Fe—F: 192.4 and Ca—F: 233.1 pm.  相似文献   

3.
The Crystal Structure of PrTe2 X‐ray diffraction single‐crystal structure analysis of PrTe2 prepared by chemical vapour transport reactions starting with praseodymium and tellurium in the presence of trace amounts of iodine also revealed superstructure reflections indicating just as for CeTe2 a (2 × 2 × 2)‐supercell of the basic anti‐Fe2As‐type structure instead of a (2 × 2 × 1)‐supercell as for LaTe2. In contrast to LaTe2 with monoclinic symmetry (space group P1c1), PrTe2 crystallizes tetragonal in the space group P4 with the lattice parameters a = 896.80(5) pm and c = 1811.9(1) pm (Z = 16). The doubling of the c‐lattice parameter compared to LaTe2 is observed due to different polyanionic structural motifs in the heights z ≈ 0 and z ≈ 1/2. These are a herringbone pattern of [Te2] dumbbell pairs (motif A; a topology which is also found in LaTe2), isolated square four‐membered [Te4] rings in z ≈ 0 (motif B) and additionally rectangular four‐membered [Te4] rings in z ≈ 1/2 (motif C). Though CeTe2 and PrTe2 are crystallizing isotypically, there are distinct differences in the interatomic distances within the polyanionic Te layers and resulting from these also a different topology of the structural motif C. The individual structural elements are causing a diffraction pattern, which is all in all to be explained by a statistical superposition of the different elements in form of microdomains.  相似文献   

4.
Crystal Structure of non‐aqueous Melaminium Chloride Melaminium chloride was obtained as colorless, needle‐shaped, single crystalline material from solid state reactions between melamin and ammonium chloride. The structure of [C3N6H7]Cl was refined by single crystal X‐ray diffraction: I2/m, Z = 8, a = 852.87(4), b = 1704.4(1) c = 918.44(4) pm and β = 92.165(6)°. The crystal structure contains melaminium ions stacked to columns along [100] and linked via N‐H···N bridges to form bands along [001]. Both of the two distinct chloride ions are stabilized by six hydrogen bonds through distorted trigonal prismatic arrangements of hydrogen atoms to yield a supramolecular structure.  相似文献   

5.
Crystal Structure of Boron Triiodide, BI3 Boron triiodide as a micro‐crystalline powder was obtained after sublimation of the reaction product of NaBH4 and iodine. An X‐ray powder diagram of the temperature‐, air‐, and light‐sensitive compound was collected at –73 °C. According to the results of the Rietveld refinement, the crystal structure of BI3 is isotypic to that of BCl3 (space group P63/m, no. 176, a = 699.09(2), c = 736.42(3) pm). The B–I bond length was determined to be 211.2(8) pm.  相似文献   

6.
NbOCl3 was obtained from a reaction of NbCl5 and Nb2O5 at 260?C. Contrary to the literature data, NbOCl3 crystallizes in the non‐centrosymmetric space group P&4macr;21m as determined by single‐crystal and powder X‐ray diffraction data (crystal: a = b = 1089.59(6) pm, c = 394.79(2) pm, Z = 4, R1 = 0.0229, wR2 = 0.0459, powder: a = b = 1086.36(6) pm, c = 393.65(2) pm). The niobium atoms are surrounded by distorted octahedra built of four chlorine atoms and two oxygen atoms in trans positions. Two such octahedra are edge‐bridged through shared chlorine atoms, forming dimers. These units are linked to each other by apical oxygen atoms forming one‐dimensional Nb2Cl6O2 chains parallel [001]. Contrary to the literature data two different Nb‐O distances are obtained.  相似文献   

7.
On the Crystal Structure of Melem C6N7(NH2)3 Single crystals of melem ( 1 ) were grown from both DMSO‐solutions and the gas phase. The structure of melem ( 1 ) was solved by single‐crystal X‐ray diffraction (P21/c, Z = 4, a = 741.66(15), b = 862.28(17), c = 1335.9(3) pm, β = 99.91(3)° R1 = 0.037 for 1098 reflections). The structure determination by X‐ray powder diffraction, which has been previously conducted, is in agreement with our data. The increased quality of the structural information allows for a more detailed understanding of the hydrogen bonding network.  相似文献   

8.
Crystal structure of AgIIF[AgIIIF4] For the first time dark brown single crystals of mixedvalent AgF[AgF4] were isolated under solvothermal conditions out of anhydrous HF/F2. The compound crystallizes in a new type of structure, triclinic with a = 499.9(2) pm, b = 1108.7(5) pm, c = 735.7(3) pm, α = 90.05(3)°, β = 106.54(4)°, γ = 90.18(4)°, spcgr. P1¯ — Ci1 (No. 2) and Z = 4.  相似文献   

9.
Ternary Halides of the A3MX6 Type. VIII On the Crystal Structure of Li3InCl6 Colorless single crystals of Li3InCl6 are obtained from a 3 : 1 molar mixture of LiCl and InCl3 via Bridgman‐type crystal growth. The crystal structure (monoclinic, C2/m, Z = 2, a = 643.2(3), b = 1109.3(3), c = 639.8(3) pm, β = 109.8(1)° R1 = 0.0549, wR2 = 0.1364 (all data) may be derived from the AlCl3‐type of structure as was previously also found for the bromides Li3MBr6 (M = Sm–Lu, Y) and iodides Li3MI6 (M = Er–Yb, Y).  相似文献   

10.
Summary Contrary to the usual pyramidalization of nitrogen electron pair centers, the spatially distorted molecular skeleton of 1,8-naphthyridin is planarized upon protonation.
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11.
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   

12.
Synthesis and Crystal Structure of K2Mn3S4 Single crystals of K2Mn3S4 have been prepared by a fusion reaction of potassium carbonate with manganese in a stream of hydrogen sulfide at 900 °C. K2Mn3S4 crystallizes in a new monoclinic layered structure type (P2/c, a = 7.244(2) Å, b = 5.822(1) Å, c = 11.018(5) Å, β = 112.33(3)°, Z = 2) which can be described as a stacking variant of the orthorhombic Cs2Mn3S4 structure type. Measurements of the magnetic susceptibilities show antiferro‐magnetic interactions.  相似文献   

13.
The Crystal Structure of the Low‐Temperature Form of Ag5Te2Cl Crystals of trimorphic Ag5Te2Cl were obtained by solid state reaction from a stoichiometric mixture of silver, tellurium, and tellurium(IV)chloride (480 °C, 4–10 days). The crystals were cooled down to –80 °C without decomposition and data collection was carried out at this temperature. The low temperature form of the title compound crystallizes in space group P21/c with lattice constants of a = 19.359(1) Å, b = 7.713(1) Å, c = 19.533(1) Å, β = 90.6°(1), V = 2916.4(1), and Z = 16. The refinement converged to residual values of R1 = 0.0381 and wR2 = 0.0847, respectively. Te and Cl atoms form empty, distorted octahedra interconnected by common vertices to give a 3D‐network. Ag atoms form clusters with Ag–Ag distances between 2.83 Å and 3.10 Å.  相似文献   

14.
Crystal Structure of BaGdCl5 Colourless single crystals of BaGdCl5 are obtained from a 1 : 2 molar mixture of BaCl2 and GdCl3. It crystallizes with the monoclinic space group C2/c with a = 552.1(2), b = 1925.7(5), c = 687.4(2) pm, β = 93.25(4)° in a new structure. Ba2+ and Gd3+ have coordination numbers of 8 + 2 and 8, respectively.  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 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   

17.
Crystal Structure of Potassium Monomethylcarbonate Potassium monomethylcarbonate KCH3CO3 was obtained from reaction of dimethylcarbonate with potassium hydroxide in methanole. The crystal structure was determined (triclinic, P1 (no. 2), Z = 2, a = 380.9(2) pm, b = 558.9(3) pm, c = 985.3(3) pm, α = 100.71(2)°, β = 90.06(3)°, γ = 92.48(3)°, V = 205.9(2) · 106 pm3, wR(F2) = 0.054, wRobs(F) = 0.022). Structural relations between potassium monomethylcarbonate and potassium hydrogencarbonate are discussed.  相似文献   

18.
Synthesis and Crystal Structure of Sr2Rh7P6 Single crystals of Sr2Rh7P6 were obtained by reaction of the elements in molten lead at 1100 °C and investigated by X-ray methods. The compound crystallizes tetragonally (a = 11.080(2), c = 4.098(1) Å) and forms a crystal structure (P 4 21m; Z = 2) with ThCr2Si2 analogous units, which are linked with each other in a new way. Therefore the RhP4 tetrahedra form bands of edge sharing chains parallel to [001] anstead of layers as in the ThCr2Si2 type structure. The arrangement enables a part of the P atoms to form short P–P distances of 2,26 Å and space for additional Rh atoms with a likewise distorted tetrahedral coordination of P atoms is obtained.  相似文献   

19.
X-ray crystal structure analyses of sulfamide were carried out at 293 K and at 100 K:M=96.10, orthorhombic, Fdd2,Z=8,F(000)=400, Mo K, =0.71069 Å (graphite monochromator). A) 293 K:a=9.127 (1) Å,b=16.857 (5) Å,c=4.579 (1) Å,V=704.50 Å3,d x =1.812 Mgm–3, =0.648 mm–1,R=1.77%,R w =1.94% (384 reflections, 33 parameters). B) 100K:a=9.059 (1) Å,b=16.780 (8) Å,c=4.517 (1) Å,V=686.63 Å3,d x =1.859 Mgm–3, =0.665 mm–1,R=1.78%,R w =1.95% (404 reflections, 33 parameters). The sulfamide molecule shows at 293 K S-O and S-N distances of 1.429 (1) Å and 1.620 (1) Å, respectively, which are in agreement with IR data. Hydrogen positions could be determined from differenceFourier syntheses. Strong weakening of some intense low order reflections by extinction was observed, their anisotropy depends on the crystal and on temperature.
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20.
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