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1.
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During an attempt to grow crystals of the nonlinear optical material Cd3Zn3B4O12 using a KBF4 flux, crystals of a new cadmium dizinc potassium borate fluoride compound, CdZn2KB2O6F, were unexpectedly isolated. The structure consists of layers constructed of distorted corner‐sharing ZnO3F tetrahedra and BO3 triangles. Both Zn and B reside on threefold rotation axes, while the F anion is located at a site of 3.2 symmetry. The CdII (site symmetry ) and K+ (site symmetry 3.2) ions occupy six‐ and nine‐coordinate interlayer sites, respectively. The BO3 triangles and ZnO3 pyramids from the ZnO3F tetrahedra share bridging O atoms with each other to form an extended [ZnBO3] layer parallel to (001). Although these layers are similar to the [MBO3] layers seen in other compounds, they are uniquely bridged here by the Cd centres and F anions to form a three‐dimensional framework. In so doing, a series of channels is formed along the [010] direction and the K+ cations are found in these channels.  相似文献   

3.
A novel beryllium borate CsBe4(BO3)3 has been grown in crystals by high-temperature flux method using spontaneous nucleation technique for the first time. The crystal structure of this compound was determined by single crystal X-ray diffraction analysis. It crystallizes in the orthorhombic space group Pnma with lattice parameters a = 8.3914(5) Å, b = 13.3674(7) Å, c = 6.4391(3) Å, Z = 4, V = 722.28(7) Å3. The crystal takes the same structure type as Rb analog based on the units of BO3 triangles and BeO4 tetrahedrons, displaying a three-dimensional tunnel structure with Cs atoms filling in the cages. The IR spectrum confirms the presence of BO3 groups and the UV–vis–IR diffuse reflectance spectrum exhibits this compound has a short UV cut-off edge below 200 nm. Band structures and density of states were calculated.  相似文献   

4.
《Solid State Sciences》2001,3(4):461-468
Single crystals of synthetic Li3InB2O6 were obtained by heating a mixture of Li2CO3, In2O3 and B2O3; its formula was determined by the resolution of the structure from X-ray diffraction data. The compound is monoclinic, space group P21/n; the unit cell parameters are a=5.168(5) Å, b=8.899(9) Å, c=10.099(10) Å, β=91.112(17)°; Z=4. The crystal structure was solved from 669 reflections until R=0.0249; it exhibits a three-dimensional framework of vertex-sharing InO5 trigonal bipyramids and BO3 triangles, which isolates Li ions in channels. This structure is characterized by unusual oxygenated environments of In cations and of one of the three Li cations, which are forming more or less regular trigonal bipyramids. This compound melts incongruently at 827 °C; the powder may be obtained by annealing at 750 °C a mixture of Li2CO3, In2O3 and B2O3.  相似文献   

5.
The present study reports on a novel barium acetato-propionate complex, obtained by the reaction of barium acetate with propionic acid, used as an oxide precursor with applications in superconducting thin films deposition. The molecular structure has been determined by X-ray diffraction on single crystals and demonstrated to be [Ba7(CH3CH2COO)10(CH3COO)4·5H2O]. The barium acetato-propionate is a three-dimensional channel-type polymer. The thermal decomposition of the barium precursor has been studied by simultaneous differential thermal analysis-thermogravimetry-mass spectrometry (DTA-TG-MS) in air at a heating rate of 10 °C/min. Based on these analyses, infrared spectroscopy was further used to characterize the precursor solution by the step-wise addition of the reagents. The X-ray diffraction on the precursor powder at different temperatures was performed.  相似文献   

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7.
《Solid State Sciences》2012,14(7):936-940
A new compound, K3ZnB5O10, has been synthesized by solid-state reaction. It crystallizes in the monoclinic system, space group P21/n with unit–cell parameters a = 7.6391(5) Å, b = 19.2304(13) Å, c = 7.6905(5) Å, β = 116.698(4)° and Z = 4. The structure of the compound is solved by the direct methods and refined to R1 = 0.0286 and wR2 = 0.0600. K3ZnB5O10 contains a two-dimensional ZnB5O10 layer, which forms by connecting isolated double ring [B5O10] groups and ZnO4 tetrahedra. The K atoms filling in the interlayer and intralayer link the layers together. Functional groups presented in the sample were identified by FTIR spectrum. UV–vis–NIR diffuse reflectance spectrum exhibits ultraviolet cutoff edge is about 190 nm. The DSC analysis proves that K3ZnB5O10 is a congruently melting compound.  相似文献   

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A new quaternary oxide, BiGaTi4O11 (bismuth gallium tetratitanium undecaoxide), was prepared by heating a mixture of the binary oxides at 1373 K in air. BiGaTi4O11 melts at 1487 K and prismatic single crystals were obtained from a sample melted at 1523 K and solidified by furnace cooling. The structure of BiGaTi4O11 was analyzed using single‐crystal X‐ray diffraction to be of a new type that crystallized in the space group Cmcm. A Bi3+ site is coordinated by nine O2? anions, and three oxygen‐coordinated octahedral sites are statistically occupied by Ga3+ and Ti4+ cations. A relative dielectric constant of 46 with a temperature coefficient of 57 ppm K?1 in the temperature range 297–448 K was measured for a polycrystalline ceramic sample at 150 Hz–1 MHz with a dielectric loss tan δ of less than 0.01. Electrical resistivities measured at 1073 K by alternating‐current impedance spectroscopic and direct‐current methods were 1.16 × 10?4 and 1.14 × 10?4 S cm?1, respectively, which indicates that electrons and/or holes were conduction carriers at high temperature. The optical band gap estimated by the results of diffuse reflectance analysis was 2.9–3.0 eV, while the band gap obtained from the activation energy for electrical conduction was 3.5 eV.  相似文献   

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11.
A new fluoride borate crystal, CdZn2KB2O6F, has been synthesized by flux-supported solid-state reaction. The crystal structure has been determined by single-crystal X-ray diffraction. It crystallizes in the trigonal space group with a=5.0381(6) Å, b=5.0381(6) Å, c=15.1550(19) Å, α=90.00°, β=90.00°, γ=120.00°, Z=2. The crystal represents a new structure type in which ZnBO3 layers are connected through bridging fluorine and cadmium atoms alternately along the c-axis. K+ cations are filled in the intralayer open channels to balance charge. IR and Raman spectra further confirm the crystal structure. Photoluminescent measurement reveals that CdZn2KB2O6F exhibits blue fluorescence at room temperature in the solid-state.  相似文献   

12.
Cs(3)Mn(2)O(4), a new member of the small family of ternary manganese (II/III) mixed-valent compounds, has been synthesized via the azide/nitrate route and studied using powder and single crystal X-ray diffraction, magnetic susceptibility measurements and density functional theory (DFT). Its crystal structure (P2(1)/c, Z = 8, a = 1276.33(1) pm, b = 1082.31(2) pm, c = 1280.29(2) pm, β = 118.390(2)°) is based on one-dimensional MnO(2)(1.5-) chains built up from edge-sharing MnO(4) tetrahedra. The title compound is the first example of an intrinsically doped transition metalate of the series A(x)MnO(2), (A = alkali metal) where a complete 1:1 charge ordering of Mn(2+) and Mn(3+) is observed along the chains (-Mn(2+)-Mn(3+)-Mn(2+)-Mn(3+)-). From the magnetic point of view it basically consists of ferrimagnetic MnO(2) chains, where the Mn(2+) and Mn(3+) ions are strongly antiferromagnetically coupled up to high temperatures. Very interestingly, their long-range three-dimensional ordering below the Néel temperature (T(N)) ~12 K give rise to conspicuous field dependent magnetic ordering phenomena, for which we propose a consistent picture based on the change from antiferromagnetic to ferromagnetic coupling between the chains. Electronic structure calculations confirm the antiferromagnetic ordering as the ground state for Cs(3)Mn(2)O(4) and ferrimagnetic ordering as its nearly degenerate state.  相似文献   

13.
Potassium bis(malonato)borate C6H4BKO8 (I) was synthesized for the first time in an aqueous medium. Well-shaped single crystals were formed. Their X-ray diffraction structure (space group P \(\overline 1 \), a = 7.4073(2) Å, b = 7.9161(2) Å, c = 9.0755(2) Å, α 113.225(1)°, β = 91.553(1)°, γ = 104.760(2)°, Z = 2) was refined by the full-matrix least-squares method in the anisotropic (K, C, O, B) or isotropic (H) approximations to R1 = 0.394, wR2 = 0.1080, 2661 independent reflections (Bruker-Nonius KappaCCD, λMoK α radiation). The structure is formed by spirane-type complex anions and potassium cations. A complex anion consists of two malonic acid molecules coordinated in the bidentate mode to the same four-coordinate boron atom. The K+ coordination geometry is an irregular nine-vertex polyhedron formed by the oxygen atoms of seven complex anions. The structure of compound I is layered.  相似文献   

14.
A new semiorganic single crystal, tris(allylthiourea)silver(I) nitrate was grown from an aqueous solution containing silver(I) nitrate and allylthiourea by slow evaporation solution growth technique at room temperature. The crystal belongs to trigonal system with centrosymmetric space group R3 and the cell parameters are, a = 12.5090(4) Å, b = 12.5090(4) Å, c = 21.7130(8) Å, V = 3348.89 Å3, and Z = 6. The various functional groups present in the molecule are confirmed by Fourier transformed infrared spectroscopy. High transmittance is observed in the visible region and band-gap energy is calculated by Kubelka–Munk algorithm. The structure and the crystallinity of the materials were further confirmed using powder X-ray diffraction analysis. Microhardness studies were also carried out to elucidate the mechanical behavior. Thermogravimetric and differential thermal analysis reveal the purity of the sample and no decomposition is observed up to the melting point.  相似文献   

15.
Single crystals of a new compound, BaBi2B4O10 were grown by cooling a melt with the stoichiometric composition. The crystal structure of the compound has been solved by direct methods and refined to R1=0.049 (wR=0.113) on the basis of 1813 unique observed reflections (|Fo|>4σ|Fo|). It is monoclinic, space group P21/c, a=10.150(2), b=6. 362(1), c=12.485(2) Å, β=102.87(1)o, V=786.0(2) Å3, Z=4. The structure is based upon anionic thick layers that are parallel to (001). The layers can be described as built from alternating novel borate [B4O10]8− chains and bismuthate [Bi2O5]4− chains extended along b-axis. The borate chains are composed of [B3O8]7− triborate groups of three tetrahedra and single triangles with a [BO2] radical. The borate chains are interleaved along the c-axis with rows of the Ba2+ cations so that the Ba atoms are located within the layers. The layers are connected by two nonequivalent Ba-O bonds as well as by two equivalent Bi-O bonds with bond valences in the range of 0.2-0.3 v.u.Thermal expansion of BaBi2B4O10 studied by high-temperature X-ray powder diffraction in the temperature range of 20-700 °C (temperature step 30-35 °C) is highly anisotropic. While the b and c unit-cell parameters increase almost linearly on heating, temperature dependencies of a parameter and β monoclinic angle show nonlinear behavior. As a result, on heating orientation of thermal expansion tensor changes, and bulk thermal expansion increases from 20×10−6 °C−1 at the first heating stage up to 57×10−6 °C−1 at 700 °C that can be attributed to the increase of thermal mobility of heavy Bi3+ and Ba2+ cations.  相似文献   

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17.
Single crystals of tribarium diyttrium hexaborate, which crystallized in the cubic system, have been obtained by spontaneous crystallization from a high‐temperature melt using Li2O–BaO–B2O3 as flux. Its structure is composed of isolated [B2O5]4− groups, irregular BaO9 polyhedra and regular YO6 polyhedra which occupy alternate sites running along the [111] direction. Irregular BaO9 polyhedra and regular YO6 polyhedra construct a three‐dimensional framework, which is reinforced by [B2O5]4− groups.  相似文献   

18.
A new complex [Cs(Db18C6)2]+[FeCl4]? was prepared and studied by X-ray diffraction (orthorhombic, space groupP21212,a = 22.934 Å,b= 24.024 Å,c= 16.665 Å,Z= 8; direct method, anisotropic full-matrix least-squares refinement,R= 0.087 for all 8800 independent reflections; CAD4 automated diffractometer, λMoK α. Two independent [FeCl4]? anions have a slightly distorted tetrahedral structure. Two independent host-guest type complex cations [Cs(Db18C6)2]+ have a sandwich structure. The Cs+ cation is located between two Db18C6 crown ligands below and above the centers of their 18-membered macrocycles and is coordinated by all 12 O atoms. The coordination polyhedron of Cs+ (C.N. 12) is a distorted hexagonal antiprism rotated toward a hexagonal prism.  相似文献   

19.
Kim Y  Martin SW 《Inorganic chemistry》2004,43(9):2773-2775
The thioborate phase Ba7(BS3)4S was synthesized from solid state reaction and its crystal structure determined by single crystal X-ray diffraction analysis. It crystallizes in the monoclinic space group C2/c (No. 15) with a = 10.1750(15) A, b = 23.970(4) A, c = 10.1692(15) A, beta = 90.095(2) degrees, and Z = 4. The structure consists of isolated trigonal planar (BS3)3- anions, and isolated S2- anions and Ba2+ cations. The additional sulfur anions have five-fold barium coordination, while the barium cations are coordinated by eight or nine sulfur atoms. Powder X-ray diffraction patterns from a bulk sample are compared to the calculated diffraction pattern from the single crystal structural analysis, and there is excellent agreement in general. The vibrational modes of the isolated (BS3)3- units were measured from Raman scattering and IR absorption spectra, and the frequencies agree very well with those found for similar orthothioborate phases.  相似文献   

20.
The crystal structure of the layered acid phosphate, AlH2P3O10.2H2O, has been determined and provides a new structure-type for a series of metal phosphates with interlamellar regions likely to be highly suited to intercalation behaviour.  相似文献   

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