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1.
A new compound α‐SrGaBO4 has been synthesized by solid state reaction at high temperatures, and its structure has been solved by direct methods from powder X‐ray diffraction. α‐SrGaBO4 has an orthorhombic system, Pccn space group, with lattice parameters a = 15.3154(7) Å, b = 8.9186(4) Å, c = 5.8130(3) Å, and Z = 8. The structure consists of infinite chains run parallel to the c axis and built up of GaO4 tetrahedral and BO3 triangles. The basic unit of these chains is a six ‐ membered Ga2BO8 ring formed by two GaO4 tetrahedra and one BO3 triangles. The Sr atom is bonded to eight oxygen atoms. The strontium atoms serve to hold the chains together through co‐ordination with oxygen atoms. DTA curve of noncrystalline glassy SrGaBO4 was discussed. The XRD results show no phase transition occurs between ‐173 °C and 127 °C. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

2.
The X‐ray diffraction has revealed that the polycrystalline hexagonal structured α‐In2Se3 thin films grown at substrate temperature of 200 °C with the unit cell parameters a = 4.03 Å and c = 19.23 Å becomes polycrystalline hexagonal structured InSe with a unit cell parameters of a = 4.00 Å and c = 16.63 Å by Cd‐doping. The analysis of the conductivity temperature dependence in the range 300‐40 K revealed that the thermionic emission of charged carriers and the variable range hopping are the predominant conduction mechanism above and below 100 K, respectively. Hall measurements revealed that the mobility is limited by the scattering of charged carriers through the grain boundaries above 200 K and 120 K for the undoped and Cd‐doped samples, respectively. The photocurrent (Iph) increases with increasing illumination intensity (F) and decreasing temperature up to a maximum temperature of ∼100 K, below which Iph is temperature invariant. It is found to have the monomolecular and bimolecular recombination characters at low and high illumination intensities, respectively. The Cd‐doping increases the density of trapping states that changes the position of the dark Fermi level leading to the deviation from linearity in the dependence of Iph on F at low illumination intensities.  相似文献   

3.
The crystal structure of 1‐allyl‐5‐(4‐methylbenzoyl)‐4‐(4‐methylphenyl)pyrimidine‐2(1H)‐thione (C22H20N2OS) has been determined from three dimensional single crystal X‐ray diffraction data. The title compound crystallizes in the monoclinic space group P 21/c, with a = 10.6674(13), b = 10.1077(7), c = 17.9467(19) Å, β = 98.460(9)°, V = 1914.0(3) Å3, Dcalc = 1.251 g cm–3, Z = 4. In the title compound, the allyl group shows positional disorder. Molecules are linked by C‐H···O, C‐H···N and C‐H···S intermolecular interactions forming two‐dimensional network. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

4.
The structure of the title compound, C15H13N4OCl was determined by single crystal X‐ray diffraction technique. The structure consists of a p‐chlorobenzylamino moiety and triazol and phenyl rings. The title compound crystallizes in the monoclinic space group P21/c with a = 14.368(3), b = 6.255(3), c = 17.631(3) Å, β = 113.24(3)°, Z = 4, V = 1455.8(8) Å3 and Dx = 1.372 gcm‐3. The structure was solved by direct methods and refined by full‐matrix least‐squares method (R=0.0477). The dihedral angle between the triazole moiety and the phenyl ring is 28.8(3)°. The molecular packing is stabilized by N‐H…N and N‐H…O types of inter molecular hydrogen bonds. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

5.
The title compound, C22H19N5O2, was prepared and its structure was determined by X‐ray diffraction [CCDC 216074]. The compound crystallizes from ethanol in the orthorhombic system, space group P212121, with unit cell parameters: a =10.048(1) Å, b = 13.935 (2) Å, c =14.607(2) Å, Z =4, and V=2045.3(5) Å3. The crystal structure was solved by direct methods and refined by full‐matrix least‐squares to a final R‐value of 0.0516 with 3621 unique reflections. The central six‐membered ring of the compound has a boat conformation and is not homoaromatic, in which adjacent atoms N1 and N4 deviate from the plane of the ring by 0.4546(33) Å and 0.3786(33) Å, respectively. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

6.
Single‐crystals of the layered copper hydroxide acetate Cu2(OH)3(CH3COO)·H2O were synthesized by heating copper acetate solution at 60 °C. The standard synthesis of the title compound based on slow titration of copper acetate solution with NaOH yielded materials with worse morphology and an additional phase present. The obtained products were characterized with powder X‐ray diffraction, high temperature powder X‐ray diffraction, scanning electron microscopy and infrared spectroscopy. The crystal structure was determined from single‐crystal X‐ray diffraction data, collected both at 120 K and at 293 K. The title compound crystallizes in the monoclinic botallackite‐type layered structure, space group P 21, with the lattice parameters a = 5.5776(3) Å, b = 6.0733(2) Å, c = 18.5134(8) Å, β = 91.802(4)° and a = 5.5875(4)Å, b = 6.0987(4) Å, c = 18.6801(10)Å, β = 91.934(5)° for 120 K and for 293 K, respectively. Acetate groups and water molecules are interlayered between corrugated sheets of edge‐sharing CuO6 octahedra exhibiting strong distortion resulted from the Jahn‐Teller effect. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

7.
The title compound (C9H7Br3) crystallizes in the triclinic space group with Z = 2; R = 0.043 for 1518 observed reflections [I = 2σ (I)]. The average Br‐C distance is 1.974 Å, Br‐C‐C angle is 110.0°. The five‐membered ring adopts a somewhat flattened structure. The atoms C1 and C3 have opposite configurations. The whole molecule has approximate (non‐crystallographic) Cs‐symmetry.  相似文献   

8.
Single crystals of Ca2FeO3Cl have been obtained as a by product during single crystal growth experiments of calcium ferrates from a CaCl2 flux. The reddish‐brown optically uni‐axial crystals adopt the tetragonal space group P4/nmm with a = 3.8381(4) Å and c = 13.685(2) Å and Z = 2 formula units per cell. The structure has been determined from a single crystal diffraction data set collected at room conditions and refined to final residual R(|F|) = 0.053 for 163 observed independent reflections with I > 2σ(I). Ca2FeO3Cl belongs to the structure family of the Ruddlesden‐Popper series with n = 1, which is also referred to as the K2NiF4‐type. Main building units are layers of perovskite type corner connected FeO5Cl‐octahedra perpendicular to [001]. The two crystallographically independent calcium ions are located between the octahedral layers and are coordinated by nine ligands each: Ca1 (4×O + 5×Cl) and Ca2 (9×O). Following prior studies Ca2FeO3Cl crystallizes in space group P4. However, the present investigation shows clearly that this assignment is incorrect and that the compound has been described in an unnecessarily low symmetry.  相似文献   

9.
Assembly of 5‐methoxyisophthalic acid (H2moip) with cadmium(II) ions in the presence of neutral ancillary 1,3‐bis(4‐pyridyl)propane (bpp) yields a new coordination polymer, [Cd(moip)(bpp)(H2O)]n·nH2O ( 1 ). X‐ray single‐crystal diffraction determination reveals that complex 1 crystallizes in the space group C2/c of monoclinic crystal system: a = 14.545(2), b = 18.749(3), c = 17.359(3) Å, β = 105.480(2)º. Complex 1 is a 4‐connected 3D diamondoid topological framework with a 2‐fold interpenetration. Interestingly, the dense adamantine cages with inherent microporous structure are filled with free water molecules to further stabilize the coordination network.  相似文献   

10.
The structure of the semiconducting alloy Cu2Cd0.5Mn0.5GeSe4 was refined from an X‐ray powder diffraction pattern using the Rietveld method. The present alloy crystallizes in the wurtz‐stannite structure, space group Pmn21 (No 31), and unit cell parameters values of a = 8.0253(2) Å, b = 6.8591(2) Å, c = 6.5734(2) Å and V = 361.84(2) Å3. The structure exhibits a three‐dimensional arrangement of slightly distorted CuSe4, Cd(Mn)Se4 and GeSe4 tetrahedras connected by corners. © 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim  相似文献   

11.
The ternary compound Cu2SnTe3 crystallizes in the Imm2 (Nº 44) space group, Z = 2, with a = 12.833(4) Å, b = 4.274(1) Å, c = 6.043(1) Å, V = 331.5(1) Å3. Its structure was refined from X‐ray powder diffraction data using the Rietveld method. The refinement of 25 instrumental and structural variables led to Rp = 10.2%, Rwp = 11.8%, Rexp = 7.7%, RB = 10.6%, S = 1.6 and χ2 = 2.6, for 5501 step intensities and 163 independent reflections. This compound is isostructural with Cu2GeSe3, and consists of a three‐dimensional arrangement of slightly distorted CuTe4 and SnTe4 tetrahedra connected by common corners. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

12.
A new coordination polymer, [Ag3hmt3(μ3 ‐btc)]·5H2O (1) (hmt = hexamethylenetetramine, btc=1,3,5‐benzenetricarboxlic), has been successfully synthesized. Crystal data: P21/a, a = 11.9906(2) Å, b = 17.3689(2) Å, c = 16.96100(10) Å, β = 101.9820(14)°, V = 3455.40(7) Å3, Z = 4, Dc = 2.002 Mg/m3. In the hexagonal structure of Ag‐hmt unit, each Ag‐hmt unit comprises three Ag atoms and three hmt ligands. The μ3 ‐btc ligands bridge adjacent two‐dimensional honeycomb‐like Ag‐hmt layers to form three‐dimensional networks. Structure analysis show that hydrogen bonds play a key role for the stable structure in the compounds. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

13.
The crystallization of alkali‐earth phosphates in the melts of Cs2O‐P2O5‐MIIO (MII – Ca, Sr, Ba) pseudo‐ternary systems have been investigated at various Cs/P molar ratios and at fixed value of MII/P equal to 0.15. Type of the phosphate which crystallizes in melts depends on the Cs/P initial ratio. Crystallization fields of CsMIIP3O9, MII2P2O7 and Cs2MIIP2O7 were briefly investigated and characterized. The new diphosphate Cs2CaP2O7 has been obtained and investigated by the single crystal and powder X‐ray diffraction and FTIR‐ spectroscopy. It crystallizes in C 2/m space group, with the following parameters of the monoclinic cell: a = 10.261(2), b = 5.9316(12), c = 7.2404(14) Å, β = 118.54(3)°. The architecture of [CaP2O7]2‐ anionic sublattice, which is built up from [CaO6] octahedra and [P2O7] bitetrahedra, interlinked via the common oxygen vertices, gives rise to formation of hexagonal tunnels along crystallographic direction b, where caesium atoms are located. One of the most remarkable features of the structure is specific positional disorder of the diphosphate group, which is connected with the existence of two equiprobable half‐occupied sites of the bridging oxygen. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

14.
A chiral complex of (R)‐2‐((pyridin‐2‐ylmethylene)amino)‐2′‐hydroxy‐1,1′‐binaphthyl ( L ) with hydrated nickel (II) acetate has been synthesized and spectroscopically characterized. The crystal structure of [NiL2(CH3OH)(CH3COO)]CH3COO·CH3OH has been determined by single‐crystal X‐ray diffraction. The complex crystallizes in the orthorhombic space group P 2(1) 2(1) 2(1) with cell constants a = 15.1035 (19), b = 17.836 (2), c = 18.730 (2)Å, α = β = γ = 90.00°, Z = 4. The structure was solved by direct methods and refined to R = 0.0346 (wR2 = 0.0863). The analytical result of the crystal structure indicates that a pair of L ligands chelate to a Ni (II) atom in an asymmetric fashion with one Ni‐N bond being longer than the other, the Ni (II) atom is further coordinated by one methanol molecule and one acetate anion to form a distorted octahedral geometry. In the crystal of the complex, the coordination cation [NiL2(CH3OH)(CH3COO)]+, the uncoordinated methanol molecule and uncoordinated acetate anion are further assembled into one‐dimensional chain structure via intermolecular hydrogen bonds along the a‐axis. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

15.
The title compound (C19H21F3N2O5) has been determined from three dimensional X‐ray diffraction data. The crystals are monoclinic, a = 7.626(4)Å, b = 17.515(4)Å, c = 15.066(3)Å, β = 101.02(3)°, V = 1975(1)Å3, Z = 4, Dcalc = 1.393g cm‐3, space group P21/c. The structure was solved by direct methods and refined by full‐matrix least‐squares method (R = 0.039).  相似文献   

16.
Crystals of the double sulfate CaMg2(SO4)3 have been obtained by solid‐state reactions of stoichiometric amounts of anhydrous CaSO4 and MgSO4 in sealed and evacuated silica tubes with chlorine gas as mineraliser. The crystal structure was determined from single crystal X‐ray diffractometer data [P 63/m, Z = 2, a = 8.3072(4), c = 7.3057(8) Å, R [F2 > 2σ (F2)] = 0.0317, wR (F2 all) = 0.0785, 476 structure factors, 33 variable parameters] and consists of distorted [CaO6] octahedra (3 symmetry), [MgO6] octahedra (3 symmetry) and SO4 tetrahedra (m symmetry) as single building units. The structure is made up of 1[CaO6/2] chains of face‐sharing [CaO6] octahedra that extend parallel to [001], alternating with columns of face‐sharing [MgO3/1O3/2]2 dimers. Both types of chains are linked via corner‐sharing with SO4 tetrahedra into a three‐dimensional framework structure. Although the compound crystallizes in a new structure type, it is topologically related to the NaZr2(PO4)3 (Nasicon) structure, and a comparative discussion between both structural arrangements is given. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

17.
The crystal structure of β‐CsB5O8 has been determined from X‐ray powder diffraction data using synchrotron radiation: Pbca, a = 7.8131(3) Å, b = 12.0652(4) Å, c = 14.9582(4) Å, Z = 8, ρcalc = 2.967 g/cm3, R‐p = 0.076, R‐wp = 0.094. β‐CsB5O8 was found to be isostructural with β‐KB5O8 and β‐RbB5O8. The crystal structure consists of a double interlocking framework built up from B‐O pentaborate groups. The crystal structure exhibits a highly anisotropic thermal expansion: αa = 53, αb = 16, αc = 14 · 10‐6/K; the anisotropy may be caused by partial straightening of the screw chains of the pentaborate groups. The similarity of the thermal and compositional (Cs‐Rb‐K substitution) deformations of CsB5O8 is revealed: increasing the radius of the metal by 0.01 Å leads to the same deformations of the crystal structure as increasing the temperature by 35°C. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

18.
The structures of the title compounds C26H37N2O2Sn ( I ) and C14H9IN2O2 ( II ) were determined by single‐crystal X‐ray diffraction technique. Compound I crystallizes in the triclinic space group P1 with a = 9.560(3) Å, b = 16.899(6) Å, c = 17.872(5) Å, α = 65.957(7)°, β = 83.603(5)°, γ ( = 75.242(5)°, V = 2549.8(13) Å3, Z = 4, and D =1.374 g/cm3. The compound consists of a quinazolinone ring with phenol and tributylstannyl moieties. Compound II crystallizes in the monoclinic space group P21/c with a = 7.6454(12) Å, b = 5.9270(9) Å, c = 27.975(4) Å; α = 90°, β = 95.081(3)°, γ = 90°, V = 1262.7(3) Å3, Z = 4, and D = 1.915 g/cm3. The compound consists of a quinazolinone ring with phenol and iodine substituents. For both I and II , the short intramolecular O–H…N and two long intermolecular N–H…O hydrogen bonds are highly effective in holding the molecular system in a stable state. (© 2006 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

19.
A supramolecular compound, {[CuMn(pydc)2(H2O)5]·2H2O} ( 1 ) (pydc = pyridine‐2,6‐dicarboxylate dianion), has been synthesized and characterized by single‐crystal X‐ray diffraction. Single‐crystal X‐ray analysis reveals that it crystallizes in the triclinic space group P‐1, a = 8.4763(17) Å, b = 9.7715(19) Å, c = 13.909(3) Å, α =101.234(3)°, β =102.520(3)°, γ= 97.375(4)°. Two mixed‐metal ions exhibit similar coordinated geometries with octahedron. 1 possesses a 3‐D unusual supramolecular network featuring 1D water tape. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

20.
X‐ray powder technique was used in the investigation of AgCd2GaS4–'AgZn2GaS4' section to determine the region of AgCd2GaS4‐based solubility. It was established that the solid solution forms up to 75 mol.% 'AgZn2GaS4'. The refinement of AgCd0.5Zn1.5GaS4 structure was performed. This alloy crystallizes in orthorhombic structure (space group Pmn21 ) with unit cell parameters a =0.78772(2), b =0.67221(2), c =0.64019(2) nm, V =0.33899(3) nm3. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   

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