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1.
Chalcogenohalogenogallates(III) and -indates(III): A New Class of Compounds for Elements of the Third Main Group. Preparation and Structure of [Ph4P]2[In2SX6], [Et4N]3[In3E3Cl6] · MeCN and [Et4N]3[Ga3S3Cl6] · THF (X = Cl, Br; E = S, Se) [In2SCl6]2?, [In2SBr6]2?, [In3S3Cl6]3?, [In3Se3Cl6]3?, and [Ga3S3Cl6]3? were synthesised as the first known chalcogenohalogeno anions of main group 3 elements. [Ph4P]2[In2SCl6] ( 1 ) (P1 ; a = 10.876(4) Å, b = 12.711(6) Å, c = 19.634(7) Å, α = 107.21(3)°, β = 96.80(3)°, γ = 109.78(3)°; Z = 2) and [Ph4P]2[In2SBr6] ( 2 ) (C2/c; a = 48.290(9) Å, b = 11.974(4) Å, c = 17.188(5) Å, β = 93.57(3)°, Z = 8) were prepared by reaction of InX3, (CH3)3SiSSi(CH3)3 and Ph4PX (X = Cl, Br) in acetonitrile. The reaction of MCl3 (M = Ga, In) with Et4NSH/Et4NSeH in acetonitrile gave [Et4N]3[In3S3Cl6] · MeCN ( 3 ) (P21/c; a = 17.328(4) Å, b = 12.694(3) Å, c = 21.409(4) Å, β = 112.18(1)°, Z = 4), [Et4N]3[In3Se3Cl6] · MeCN ( 4 ) (P21/c; a = 17.460(4) Å, b = 12.816(2) Å, c = 21.513(4) Å, β = 112.16(2)°, Z = 4), and [Et4N]3[Ga3S3Cl6] · THF ( 5 ) (P21/n; a = 11.967(3) Å, b = 23.404(9) Å, c = 16.260(3) Å, β = 90.75(2)°, Z = 4). The [In2SX6]2? anions (X = Cl, Br) in 1 and 2 consist of two InSX3 tetrahedra sharing a common sulfur atom. The frameworks of 3, 4 and 5 each contain a six-membered ring of alternating metal and chalcogen atoms. Two terminal chlorine atoms complete a distorted tetrahedral coordination sphere around each metal atom.  相似文献   

2.
Two ternary metal chalcogenides, Ba2In2Q5 (Q = S, Se) were successfully synthesized by solid‐state reactions. They are isostructural and crystallize in the orthorhombic space group Pbca (no. 61). Both of them have a similar three‐dimensional (3D) framework structure, which is composed of [InQ4] (Q = S, Se) tetrahedra that are alternatingly connected on layer in the ab plane, with Ba2+ cations arranged between In–S or In–Se layers for electric charge balance. The measured Raman and IR spectra show that title compounds have broad transparency range up to 20 μm. From the UV/Vis/NIR diffuse reflectance spectra, it can be seen that the bandgaps of Ba2In2S5 and Ba2In2S5 are 2.47 eV and 2.12 eV, which are larger than these of the calculation values (Ba2In2S5, 2.362 eV and Ba2In2Se5, 1.908 eV), respectively. The calculated partial densities of states indicate that the bandgaps are determined by the interaction of S‐3p and In‐5s (Ba2In2S5) or Se‐4p and In‐5s (Ba2In2Se5), respectively. The calculated birefringences (Δn) are about 0.03 (Ba2In2S5) and 0.05 (Ba2In2Se5) as the wavelength above 1 μm, respectively.  相似文献   

3.
Arsenidostannates with [SnAs] Nets Isostructural to Grey Arsenic: Synthesis and Crystal Structure of Na[Sn2As2], Na0.3Ca0.7[Sn2As2], Na0.4Sr0.6[Sn2As2], Na0.6Ba0.4[Sn2As2], and K0.3Sr0.7[Sn2As2] The metallic lustrous compounds Na[Sn2As2], Na0.3Ca0.7[Sn2As2], Na0.4Sr0.6[Sn2As2], Na0.6Ba0.4[Sn2As2] and K0.3Sr0.7[Sn2As2] were prepared from melts of mixtures of the elements. The compounds crystallize in the trigonal system (space group R3 m, No. 166, Z = 3) with lattice constants see in “Inhaltsübersicht”. The structures are isotypic to Sr[Sn2As2] containing puckered [SnAs] nets which are stacked with a sequence of six layers. The E(I)/E(II) atoms are located between each second [SnAs] layer in trigonal antiprismatic interstices formed by As atoms. In the resulting [Sn2As2] double layers the 2[SnAs] nets are stacked in such a way that additional Sn—Sn contacts arise.  相似文献   

4.
S5N5 [GaCl4]? and S5N5 [Ga2Cl7]?. Synthesis, IR Spectra, and Crystal Structures . S5N5[GaCl4] was obtained in high yields from gallium and trithiazyl chloride; depending on the solvent, different second products are formed: S4N4Cl[GaCl4] in dichloromethane and S3N2Cl[GaCl4] in carbon tetrachloride. These products can be separated due to their high solubility in CH2Cl2, S5N5[GaCl4] being only slightly soluble. S3N2Cl[GaCl4] can be converted to S5N5[GaCl4] with additional (NSCl)3. By the action of GaCl3 on S5N5[GaCl4], S5N5[Ga2Cl7] is formed. The IR spectra of the title compounds are reported; they differ considerably as well in number as in frequencies of the cation bands and show that the S5N5 ion has different structures depending on the anion. The crystal structures of both compounds were determined by X-ray diffraction. Crystal data: S5N5[GaCl4], orthorhombic, a = 943.8, b = 1369.0, c = 2068.8 pm, space group Pnma, Z = 8 (1381 observed reflexions, R = 0.075); S5N5[Ga2Cl7], monoclinic, a = 847.5, b = 1298.2, c = 1654.0 pm, β = 93.51°, space group P21/n, Z = 4 (1359 observed reflexions, R = 0.065). S5N5[GaCl4] is isotypic with S5N5[AlCl4], showing a heartshaped S5N5 ion, but large ellipsoids of vibration suggest the presence of some kind of disorder (statical or dynamical). In S5N5[Ga2Cl7] the S5N5 has an azulene-like structure. In both cases the cations are planar, all S? N bond lengths being approximately equal.  相似文献   

5.
Ba3N2 reacts at 950°C under pure N2 with Zr to yield dark red, air-sensitive Ba[ZrN2]. This new compound crystallizes in the tetragonal space group P4/nmm with a = 416.10(2), c = 839.2(1) pm and Z = 2. The crystal structure was solved and refined using X-ray and neutron powder diffraction data. In the nitrido zirconate [ZrN2]2? the Zr atoms exhibit a square-pyramidal coordination by five N atoms at distances of 201(3) and 220.2(2) pm. The pyramids share all the edges in the basal plane to form layers parallel to (001) with their apices alternately pointing up and down. The Ba2+ cations are integrated into these layers at the levels of the pyramidal apices. The structure can be interpreted as a stuffed PbFCl type. Ba2[NbN3] is formed by the reaction of Ba3N2 and NbN or of Ba and Nb at 1 000°C under N2. Isostructural to Ba2[TaN3] it crystallizes in the monoclinic space group C2/c with a = 613.2(3), b = 1 176.8(3), c = 1 322.9(4) pm, β = 91.65(2)°, Z = 8. The nitrido niobate anions form chains of corner sharing NbN4 tetrahedra with distances Nb? N between 188(1) and 199.9(9) pm.  相似文献   

6.
Ba5[CrN4]N: The First Nitridochromate(V) Ba5[CrN4]N is prepared by reaction of mixtures of Li3N, Ba3N2 and CrN/Cr2N (1 : 1) (molar ratio Li : Ba : Cr = 3 : 5 : 1) in tantalum crucibles at 700°C with flowing nitrogen (1 atm) within a period of 48 h. After cooling down to room temperature (60°C/h) black-shining single crystals of the ternary phase with a platy habit are obtained (monoclinic, C2/m; a = 1054.0(2) pm, b = 1170.9(3) pm, c = 937.7(2) pm, b? = 110,79(2)°; Z = 4). The crystal structure contains isolated complex anions [CrVN4]7? which nearly satisfy the ideal tetrahedral symmetry (Cr? N [pm]: 2 × 175.3(4), 2 × 175.8(5); N? Cr? N [°]: 106.8(2), 109.5(2), 2 × 109.9(2), 2 × 110,3(2)). The coordination sphere for each of the terminal nitride functions of the complex anions is completed by five neighbouring Ba2+ ions (distorted CrBa5 octahedra). The octahedra are connected via common CrBa2 faces as well as CrBa edges thereby forming condensed tetrameric octahedral groups. The isolated nitride ions which are also present in the crystal structure of Ba5[CrN4]N are in an octahedral environment of Ba2+ ions. The presence of a d1-System (Cr(V)) is confirmed by magnetic susceptibility data.  相似文献   

7.
Chloro- and Polyselenoselenates(II): Synthesis, Structure, and Properties of [Ph3(C2H4OH)P]2[SeCl4] · MeCN, [Ph4P]2[Se2Cl6], and [Ph4P]2[Se(Se5)2] By symproportionation of elemental selenium and SeCl4 in polar protic solvents the novel chloroselenates(+II), [SeCl4]2? and [Se2Cl6]2?, could be stabilized; they were crystallized with voluminous organic cations. They were characterized from complete X-ray structure analysis. Yellow-orange [Ph3(C2H4OH)P]2[SeCl4] · MeCN (space group P1 , a = 10.535(4), b = 12.204(5), c = 16.845(6) Å, α = 77.09(3)°, β = 76.40(3)°, γ = 82.75(3)° at 140 K) contains in its crystal structure monomeric [SeCl4]2? anions with square-planar coordination of Se(+II). The mean Se? Cl bond length is 2.441 Å. In yellow [Ph4P]2[Se2Cl6] (space group P1 , a = 10.269(3), b = 10.836(4), c = 10.872(3) Å, α = 80.26(3)°, β = 79.84(2)°, γ = 72.21(3)° at 140 K) a dinuclear centrosymmetric [Se2Cl6]2? anion, also with square-planar coordinated Se(+II), is observed. The average terminal and bridging Se? Cl bond distances are 2.273 and 2.680 Å, respectively. From redox reactions of elemental Se with boranate/thiolate in ethanol/DMF the bis(pentaselenido)selenate(+II) anion [Se(Se5)2]2? was prepared as a novel type of a mixed-valent chalcogenide. In dark-red-brown [Ph4P]2[Se(Se5)2] (space group P21/n, a = 12.748(4), b = 14.659(5), c = 14.036(5) Å, β = 108.53(3)° at 140 K) centrosymmetric molecular [Se(Se5)2]2? anions with square-planar coordination of the central Se(+II) by two bidentate pentaselenide ligands is observed (mean Se? Se bond lengths: 2.658 Å at Se(+II), 2.322 Å in [Se5]2?). The resulting six-membered chelate rings with chair conformation are spirocyclically linked through the central Se(+II). The vibrational spectra of the new anions are reported.  相似文献   

8.
Crystal Structures of the Polyselenides [Cs(18-Crown-6)]2Se5 · DMF, [Rb(222-Crypt)]2Se6, [Ba(15-Crown-5)2]Se6 · DMF, and [Na(12-Crown-4)2]Se7 . The title compounds have been prepared by reactions of the corresponding diselenides with excess selenium in the presence of crown ethers in dimethylformamide solutions, forming black crystals. [Cs(18-Crown-6)]2Se5 · DMF: Space group P21/m, Z = 2, 2 194 observed unique reflections, R = 0.119. Lattice dimensions at 20°C: a = 1 041.2; b = 1 496.3; c = 1 459.7 pm; β = 100.39°. The compound forms an ionic triple with Cs…Se-contacts between 374 and 381 pm. [Rb(222-Crypt)]2Se6: Space group P1 , Z = 2, 7 405 observed unique reflections, R = 0.056. Lattice dimensions at – 70°C: a = 1 106.8; b = 1 460.8; c = 1 718.8 pm; α = 89.22°; β = 86.65°; γ = 71.53°. The compound contains Se62? chains without direct contact with each other. [Ba(15-Crown-5)2]Se6 · DMF: Space group P21/n, Z = 4, 2 680 observed unique reflections, R = 0.055. Lattice dimensions at – 80°C: a = 1 051.9; b = 1 322.4; c = 2 729.9 pm; β = 100.93°. The compound contains Se62? chains, which are isolated from each other by the cations and the included DMF molecules. [Na(12-Crown-4)2]2Se7: Space group P1 , Z = 2, 7 313 observed unique reflections, R = 0.042. Lattice dimensions at – 70°C: a = 1 260.9; b = 1 433.6; c = 1 462.9 pm; α = 80.27°; β = 78.60°; γ = 69.34°. The compound contains Se72? chains without direct contacts with each other.  相似文献   

9.
Three Alkali‐Metal Erbium Thiophosphates: From the Layered Structure of KEr[P2S7] to the Three‐Dimensional Cross‐Linkage in NaEr[P2S6] and Cs3Er5[PS4]6 The three alkali‐metal erbium thiophosphates NaEr[P2S6], KEr[P2S7], and Cs3Er5[PS4] show a small selection of the broad variety of thiophosphate units: from ortho‐thiophosphate [PS4]3? and pyro‐thiophosphate [S3P–S–PS3]4? with phosphorus in the oxidation state +V to the [S3P–PS3]3? anion with a phosphorus‐phosphorus bond (d(P–P) = 221 pm) and tetravalent phosphorus. In spite of all differences, a whole string of structural communities can be shown, in particular for coordination and three‐dimensional linkage as well as for the phosphorus‐sulfur distances (d(P–S) = 200 – 213 pm). So all three compounds exhibit eightfold coordinated Er3+ cations and comparably high‐coordinated alkali‐metal cations (CN(Na+) = 8, CN(K+) = 9+1, and CN(Cs+) ≈ 10). NaEr[P2S6] crystallizes triclinically ( ; a = 685.72(5), b = 707.86(5), c = 910.98(7) pm, α = 87.423(4), β = 87.635(4), γ = 88.157(4)°; Z = 2) in the shape of rods, as well as monoclinic KEr[P2S7] (P21/c; a = 950.48(7), b = 1223.06(9), c = 894.21(6) pm, β = 90.132(4)°; Z = 4). The crystal structure of Cs3Er5[PS4] can also be described monoclinically (C2/c; a = 1597.74(11), b = 1295.03(9), c = 2065.26(15) pm, β = 103.278(4)°; Z = 4), but it emerges as irregular bricks. All crystals show the common pale pink colour typical for transparent erbium(III) compounds.  相似文献   

10.
Synthesis and Crystal Structure of [Na(12-Crown-4)2]2[Hg(Se4)2] · 1.5 DMF . The title compound has been prepared by the reaction of Na2Se4 with mercury acetate in DMF solution in the presence of 15-crown-5, forming dark red crystal needles. [Na(12-crown-4)2]2[Hg(Se4)2] · 1.5 DMF crystallizes in the space group C2/c with eight formula units per unit cell. The structure was determined with 3 824 observed unique reflections, R = 0.085. Lattice dimensions at - 70°C: a = 2 884(2), b = 1 407.7(7), c = 2 843(2) pm, β = 93.93(5)°. The structure consists of [Na(12-crown-4)2]+ ions with a sandwichlike coordination of the crown ether molecules, and of [Hg(Se4)2]2? ions, in which the mercury atom is coordinated by two tetraselenido ions in a chelating fashion. The [Hg(Se4)2]2? ions are arranged to infinite chains via Se…?Se contacts.  相似文献   

11.
Reaction of Tin Chlorides with Polysulfides. Crystal Structures of (PPh4)2[SnCl2(S6)2], (PPh4)2[Sn4Cl4S5(S3)O], and (PPh4)2[SnCl6] · S8 · 2CH3CN . The reaction of PPh4[SnCl3] with Na2S4 in acetonitrile in the presence of small amounts of water yields (PPh4)2[Sn4Cl4S5(S3)O] and minor amounts of (PPh4)2[SnCl2(S6)2], PPh4Cl · 2S8 and (PPh4)2[SnCl6]. SnCl4 is partially reduced by (PPh4)2Sx, PPh4[SnCl3] and (PPh4)2[SnCl6] · S8 · 2CH3CN being produced. According to the X-ray crystal structure determination the [Sn4Cl4S5(S3)O]2?-ion consists of an O atom that is coordinated by four Sn atoms which in turn are liked with one another by five single S atoms and one S3 group. In the [SnCl2(S6)2]2?-ion the Sn atom is octahedrally coordinated by two Cl atoms in trans arrangement and by two chelating S6 groups. Octahedral [SnCl6]2? ions and S8 molecules in the crown conformation are present in (PPh4)4[SnCl6] · S8 · 2CH3CN.  相似文献   

12.
Na5[CuO2][CO3], Na5[CuO2][SO3], Na5[CuO2][S], and Na5[CuO2][SO4] were obtained as single crystals and powders from reactions of Na2O, Cu2O, and Na2X with X = CO32—, SO32—, S2—, and SO42—, respectively. A redox reaction between CdO and Co metal occurs in the presence of Na2O and Na2X, yielding Na5[CoO2][X] with X = CO32— and S2—. From a mixture of Na2SO4, CdO and Na2O in Ni‐containers we observed the formation of Na5[NiO2][S] single crystals. Single crystals of Na25[CuO2]5[SO4]4[S] can be grown by annealing Na5[CuO2][SO3] at 600 °C, leading to the decomposition of SO32—, yielding SO42— and S2— at 550 °C. The structures have been determined from single crystal data and powder data. All structures contain the isolated complex [MO2]3— in a dumb‐bell like arrangement. The main feature of these compounds is that the anions SO42—, SO32—, CO32— and S2— are not connected to the transition metal. The formation of Na5[CuO2][X] (X = S2—, SO42—, SO32—, CO32—) has been studied by thermal analysis and in situ X‐ray diffraction techniques. Infrared spectra confirm the presence of SO42—, SO32—, and CO32—, respectively, in the structures.  相似文献   

13.
Li6+2x[B10Se18]Sex (x ≈ 2), an Ion‐conducting Double Salt Li6+2x[B10Se18]Sex (x ≈ 2) was prepared in a solid state reaction from lithium selenide, amorphous boron and selenium in evacuated carbon coated silica tubes at a temperature of 800 °C. Subsequent cooling from 600 °C to 300 °C gave amber colored crystals with the following lattice parameters: space group I2/a (at 173 K); a = 17.411(1) Å, b = 21.900(1) Å, c = 17.820(1) Å, β = 101.6(1)°. The crystal structure contains a well‐defined polymeric selenoborate network of composition ([B10Se16Se4/2]6?)n consisting of a system of edge‐sharing [B10Se16Se4/2] adamantanoid macro‐tetrahedra forming large channels in which a strongly disorderd system of partial occupied Li+ cations and additional disordered Se2? anions is observed. The crystal structure of the novel selenoborate is isotypic to Li6+2x[B10S18]Sx (x ≈ 2) [1]. X‐ray and 7Li magic‐angle spinning NMR data suggest that the site occupancies of the three crystallographically distinct lithium ions exhibit a significant temperature dependence. The lithium ion mobility has been characterized by detailed temperature dependent NMR lineshape and spin‐lattice relaxation measurements.  相似文献   

14.
Synthesis and Crystal Structure of Ba6ZnIn2Cl20 Colourless single crystals of Ba6ZnIn2Cl20 are obtained from a 6 : 3 : 2 molar mixture of BaCl2, ZnCl2 and InCl3 at 420 °C in a Pyrex ampoule. It crystallizes with the monoclinic space group P21/c (Z = 4) with a = 1957.8(2), b = 1014.69(8), c = 1778.7(2) pm, β = 110.94(1)°, in a new structure. Zn2+ is surrounded tetrahedrally and In3+ octahedrally by chloride ions. Half of the [InCl6] octahedra are isolated from each other, the other half shares common edges to form [In2Cl10] double octahedra. Ba2+ has coordination numbers of eight and nine. There are chloride ions that do not belong to Zn2+ or In3+ so that the formula may be written as Ba12Cl10[ZnCl4]2[InCl6]2[In2Cl10].  相似文献   

15.
Pentabromothio-diarsenate and -diantimonate: Preparation, Vibrational Spectra, and Crystal Structures of PPh4[As2SBr5] and PPh4[Sb2SBr5] The title compounds were obtained in CH2Br2 from PPh4Br, HBr and As2S3 or Sb2S3, respectively. Their i.r. and Raman spectra are reported. Their crystal structures were determined by X-ray diffraction. Crystal data: PPh4[As2SBr5], monoclinic, space group P21/n, Z = 4, a = 1192.3, b = 1528.1, c = 1618.0 pm, β = 95.53°, isotypic with PPh4[As2SCl5] (structure determination with 1539 observed reflexions, R = 0.052); PPh4[Sb2SBr5], triclinic, space group P1 , Z = 2, a = 1044,8, b = 1207.1, c = 1307.8 pm, α = 104.77, β = 108.63, γ = 98.34° (2398 observed reflexions, R = 0.032). Both ions, [As2SBr5]? and [Sb2SBr5]?, have the same general structure: including the lone electron pairs, the As and Sb atoms have distorted trigonal-bipyrimidal coordination, two bipyramids sharing a common edge with sulfur and bromine as bridging atoms. The [As2SBr5]? ions are associated to chains via As…Br contacts, the [Sb2SBr5]? ions form pseudodimeric units by Sb…S and Sb…Br contacts. Whereas the crystal packing of the As compound is similar to that of other PPh4+ compounds having a cation to anion ratio of 1:1, the Sb compound shows the packing principle known for 2:1 compounds.  相似文献   

16.
During an investigation of the SrO–CuO–P2O5–H2O system, single crystals of distrontium hexahydroxidocuprate(II), Sr2[Cu(OH)6], were obtained by the hydrothermal method. The blue prismatic crystals of Sr2[Cu(OH)6] adopt the same structure type as Ba2[Cu(OH)6], Sr2[Zn(OH)6] and Ba2[Zn(OH)6]. The Cu atoms, located at (0, 0, ) (site symmetry ), form mutually isolated and highly elongated Cu(OH)6 octahedra, which are interconnected to slightly distorted Sr(OH)6 trigonal prisms, forming a layered structure. The location of H atoms from difference Fourier maps and their refinement allowed the precise determination of a three‐dimensional hydrogen‐bonding network in which all hydroxide O atoms are involved. In addition, the hydrogen‐bonding topologies in Sr2[Cu(OH)6] and other similar hexahydroxidometallates with the general formulae M1[M2(OH)6], M12[M2(OH)6] and M13[M2(OH)6] were analysed in detail.  相似文献   

17.
Synthesis and Crystal Structures of (PPh4)2[In(S4)(S6)Cl] and (PPh4)2[In(S4)Cl3] InCl and PPh4Cl yield (PPh4)2[In2Cl6] in acetonitrile. This reacts with Na2S4 in presence of PPh4Cl, forming (PPh4)2[In(S4)(S6)Cl]. Its crystal structure was determined by X-ray diffraction (R = 0.075, 2 282 observed reflexions). It is isotypic with (PPh4)2[In(S4)(S6)Br] and contains anions with trigonal-bipyramidal coordination of In, Cl occupying an axial position, and the S4 and S6 groups being bonded in a chelate manner. The reaction of (PPh4)2[In2Cl6] and sulfur in acetonitrile yielded (PPh4)2[InCl5] and (PPh4)2[In(S4)Cl3]. The crystal structure analysis of the latter (R = 0.072, 4 080 reflexions) revealed an anion with distorted trigonal-bipyramidal coordination of In, the S4 group occupying one axial and one equatorial position; the S4 group shows positional disorder.  相似文献   

18.
New Oxogallates of Alkaline Metals: On K6[Ga2O6] and Rb6[Ga2O6] as well as Na3GaO3 and Cs6[Ga2O6] Due to powder and single crystal data K6[Ga2O6] a = 7.099; b = 11.116; c = 6.484 Å; ß = 101.66° and Rb6[Ga2O6] a = 7.393; b = 11.475; c = 6.798 Å; ß = 103.5° crystallize isotypic with K6[Fe2O6]; space group C2/m-C32h; As well has been prepared the hitherto unknown Na3GaO3 a = 11.48, b = 10.82, c = 6.13 Å, space-group Imcm or I2cm Z = 8; and Cs6[Ga2O6] a = 7.26, b = 12.1, c = 7.68 Å, ß = 105°, Z = 4, space-group P21/a.  相似文献   

19.
Pr4S3[Si2O7] and Pr3Cl3[Si2O7]: Derivatives of Praseodymium Disilicate Modified by Soft Foreign Anions For synthesizing both the disilicate derivatives Pr4S3[Si2O7] and Pr3Cl3[Si2O7], Pr, Pr6O11 and SiO2 are brought to reaction with S and PrCl3, respectively, in suitable molar ratios (850 °C, 7 d) in evacuated silica tubes. By using NaCl as a flux, Pr4S3[Si2O7] crystallizes as pale green, transparent single crystals (tetragonal, I41/amd, a = 1201.6(1), c = 1412.0(2) pm, Z = 8) with the appearance of slightly compressed octahedra. On the other hand, Pr3Cl3[Si2O7] emerges as pale green, transparent platelets and crystallizes monoclinically (space group: P21, a = 530.96(6), b = 1200.2(1), c = 783.11(8) pm, β = 109.07(1)°, Z = 2). In both crystal structures ecliptically conformed [Si2O7]6– units of two corner‐linked [SiO4] tetrahedra with Si–O–Si bridging angles of 131° in the sulfide and 148° in the chloride disilicate are present. In Pr4S3[Si2O7] both crystallographically independent Pr3+ cations show coordination numbers of 8 + 1 (5 S2– and 3 + 1 O2–) and 9 (3 S2– and 6 O2–). For Pr1, Pr2 and Pr3 in Pr3Cl3[Si2O7] coordination numbers of 10 (5 Cl and 5 O2–) and 9 (2 ×; 4 Cl and 5 O2– or 3 Cl and 6 O2–, respectively) occur.  相似文献   

20.
In the ternary system Se/Bi/Cl a new polycation containing phase besides the already known Se4[Bi4Cl14], Se8[Bi4Cl14], and Se10[Bi5Cl17] was discovered. Red, transparent, plate shaped crystals of Se10[Bi4Cl14] were formed by reaction of Se/SeCl4/BiCl3 in 15:1:8 molar ratio in evacuated glass ampoules applying a temperature gradient from 90 to 80 °C. The crystal structure consists of bicyclic Se102+ cations and of layered chloridobismutate anions with the cations located between the anionic planes. The atoms of the cation form a six membered ring with a Se4 chain bridging over the 1,4 positions of the Se6 ring. The anions are made up of BiCl7 polyhedra connected by common edges to layers all contain an anion of identical formula and two‐dimensional connectivity, but these polymeric chloridobismutates are not isostructural. The structural differences are discussed on basis of the different topologies of the nets made up by the bismuth atoms.  相似文献   

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