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1.
The crystal structure of a new mineral britvinite Pb7.1Mg4.5(Si4.8Al0.2O14)(BO3)(CO3)[(BO3)0.7(SiO4)0.3](OH, F)6.7 from the Lángban iron-manganese skarn deposit (V?rmland, Sweden) is determined at T = 173 K using X-ray diffraction (Stoe IPDS diffractometer, λMoKα, graphite monochromator, 2θmax = 58.43°, R = 0.052 for 6262 reflections). The main crystal data are as follows: a = 9.3409(8) ?, b = 9.3579(7) ?, c = 18.8333(14) ?, α = 80.365(6)°, β = 75.816(6)°, γ = 59.870(5)°, V = 1378.7(2) ?3, space group P1, Z = 2, and ρcalcd = 5.42 g/cm3. The idealized structural formula of the mineral is represented as [Pb7(OH)3F(BO3)2(CO3)][Mg4.5(OH)3(Si5O14)]. It is demonstrated that the mineral britvinite is a new representative of the group of mica-like layered silicates with structures in which three-layer (2: 1) “sandwiches” composed of tetrahedra and octahedra alternate with blocks of other compositions, such as oxide, oxide-carbonate, oxide-carbonate-sulfate, and other blocks. The tetrahedral networks (Si5O14)∞∞ consisting of twelve-membered rings are fragments of the britvinite structure. Similar networks also form crystal structures of the mineral zeophyllite and the synthetic phase Rb6Si10O23. In the crystal structures under consideration, the tetrahedral networks differ in the rotation of tetrahedra with respect to the layer plane. Original Russian Text ? O.V. Yakubovich, W. Massa, N.V. Chukanov, 2008, published in Kristallografiya, 2008, Vol. 53, No. 2, pp. 233–242.  相似文献   

2.
High-quality centimeter-sized single crystals of La1.2Sr1.8−yCayMn2O7 (0.0y0.2) were successfully grown using a floating zone method associated with an image furnace. We present the growth conditions together with a characterization of the single crystals by means of optical and electron microscopy, EDX and ICPAES analysis, DTA-TGA measurements and redox titration, X-ray powder diffraction, Laue X-ray back-reflection and neutron diffraction. We also stress the main aspects of the complex thermodynamical and kinetic behaviors of these compounds.  相似文献   

3.
The structure of the (La0.9Sr0.1)(Fe0.8Mg0.2)O3− y oxide is investigated using neutron diffraction at temperatures of 10, 295, 500, 700, and 1000 K. The results of the structure refinement are in good agreement with the experimental data on the electrical conductivity and confirm the inference that the oxidation state of iron cations is higher than 3+ and that the structure of the compound is antiferromagnetically ordered at temperatures below 500 K. Original Russian Text ? S.A. Ivanov, G.M. Kaleva, A.V. Mosunov, E.D. Politova, S.-G. Eriksson, 2008, published in Kristallografiya, 2008, Vol. 53, No. 1, pp. 69–75.  相似文献   

4.
The (Pb0.90La0.10)TiO3 [PLT] thick films (3.0 μm) with a PbO buffer layer were deposited on the Pt(1 1 1)/Ti/SiO2/Si(1 0 0) substrates by RF magnetron sputtering method. The PLT thick films comprise five periodicities, the layer thicknesses of (Pb0.90La0.10)TiO3 and PbO in one periodicity are fixed. The PbO buffer layer improves the phase purity and electrical properties of the PLT thick films. The microstructure and electrical properties of the PLT thick films with a PbO buffer layer were studied. The PLT thick films with a PbO buffer layer possess good electrical properties with the remnant polarization (Pr=2.40 μC cm−2), coercive field (Ec=18.2 kV cm−1), dielectric constant (εr=139) and dielectric loss (tan δ=0.0206) at 1 kHz, and pyroelectric coefficient (9.20×10−9 C cm−2 K−1). The result shows the PLT thick film with a PbO buffer layer is a good candidate for pyroelectric detector.  相似文献   

5.

Abstract  

A new acetyl phosphorylamidate P(O)[NHC(O)C6H4(4-NO2)][N(CH(CH3)2)(CH2C6H5)]2 has been synthesized and characterized by elemental analysis, 1H, 13C and 31P NMR, IR and single crystal X-ray diffraction. Single crystal X-ray analysis shows that it belongs to triclinic system, space group P[`1] P\bar{1} , with a = 10.5868(16) Å, b = 11.8058(18) Å, c = 12.4364(19) Å, α = 65.410(3)°, β = 67.492(4)°, γ = 85.879(3)°, V = 1,298.6(3) Å3, and Z = 2. The intermolecular PO···HN hydrogen bond makes H-bonded dimer of molecule with Ci symmetry. In the crystal network, the dimers are aggregated in the chain arrays through π-stacking between p-NO2–C6H4–C(O)–NH– moieties. Moreover, weak C–H···O and C–H···π interactions exist in the crystal network.  相似文献   

6.
Abstract  A novel binuclear Smarium (III) complex with N-(2-propionic acid)-salicyloyl hydrazone (C10H10N2O4, H3L) was prepared and characterized. The crystal structure of [Sm2(H2L)2(HL)2(H2O)4] (1) was determined by X-ray single crystal diffractometry. 1 crystallizes in the monoclinic systerm, space group P2(1)/c, with a = 0.10229(2), c = 31.549(7), b = 0.70599(15) nm, and Z = 4. In the structure, Sm(III) is nine-coordinated by carboxyl O and acyl O atoms and imido N atoms of two ligands (H2L and HL forms) and O atoms from two water molecules. H2L and HL act as tridentate ligands which form two stable five-numbered chelating rings sharing one edge in the keto form for each ligand, and the carboxyl groups of two ligands were coordinated via bidentated bridging form. The coordination polyhedron around Sm (III) was described as a monocapped square antiprism. The inter- and intramolecular hydrogen bonds resulted in a three-dimensional network and provided extra stability for the structure. The complex was researched the interaction with calf thymus DNA by electronic absorption titration and emission titration. The results show that the complex is bound to calf thymus DNA mainly by intercalation .The complex also shows good fluorescence property. Index Abstract  The title compound, [Sm2(H2L)2(HL)2(H2O)4] was synthesized by the treatment of N-(2-propionic acid)-salicyloyl hydrazone (C10H10N2O4, H3L) and Sm(NO3) · 4H2O and its crystal structure determined. Single crystal X-ray diffraction analysis reveals that Sm (III) is nine-coordinated by carboxyl O and acyl O atoms and imido N atoms of two ligands (H2L and HL forms) and O atoms from two water molecules. The carboxyl groups of two ligands were coordinated via bidentated bridging form. The coordination polyhedron around Sm (III) was described as a monocapped square antiprism. The inter- and intramolecular hydrogen bonds resulted in a three-dimensional network and provided extra stability for the structure.   相似文献   

7.
Epitaxial (La0.07Sr0.93)SnO3 [LSSO] films were deposited on CaF2 substrates by pulse laser deposition. The (1 0 0)c orientation of LSSO films was observed only on (1 1 0)CaF2, whereas (1 1 0)c orientation was found on (1 1 1)CaF2 and (1 0 0)CaF2. (0 0 1) polar axis oriented tetragonal Pb(Zr0.35Ti0.65)O3 films were grown on the fabricated (1 0 0)cLSSO∥(1 1 0)CaF2 by pulsed metal organic chemical vapor deposition. The (0 0 1)Pb(Zr0.35Ti0.65)O3∥(1 0 0)cLSSO∥(1 1 0)CaF2 stack structure exhibited about 70% transparency with an adsorption edge of approximately 330 nm.  相似文献   

8.
A new basic Nd3+ nitrate, [Nd6O(OH)8(H2O)14(NO3)6](NO3)2 · 2H2O (I), is isolated in the crystal form and studied. Compound I differs from the basic Ln nitrates containing [Ln 6O(OH)8] clusters in that it involves a larger number of water molecules. The incorporation of additional water molecules is accompanied by changes in the coordination environment of one of the three crystallographically independent Nd3+ cations. Two cations have coordination polyhedra in the form of a monocapped tetragonal antiprism with a coordination number of 9, and the third cation has a polyhedron in the form of a bicapped tetragonal antiprism with a coordination number of 10. Original Russian Text ? I.A. Charushnikova, C. Den Auwer, 2007, published in Kristallografiya, 2007, Vol. 52, No. 2, pp. 248–251.  相似文献   

9.
10.
Three heteroacidoligand uranyl complexes M 4[(UO2)2C2O4(SO4)2(NCS)2] (M = K+ (I), Rb+ (II)) and K4[(UO2)2C2O4(SeO4)2(NCS)2] (III) have been synthesized and their crystal structure has been determined by X-ray diffraction analysis. The compounds I–III are isostructural and crystallized in the monoclinic system, sp. gr. P21/c, Z = 2, a = 11.5548(3) ?, b = 7.0847(1) ?, c = 13.5172(3) ?, β = 93.130(1)°, V = 1104.90(4), R = 0.015 (I); a = 11.5854(9) ?, b = 7.3841(6) ?, c = 13.9072(9) ?, β = 95.754(3)°, V = 1183.74(15), R = 0.0235 (II); a = 11.6715(3) ?, b = 7.1418(2) ?, c = 13.8546(1) ?, β = 93.539(1)°, V = 1152.66(5), R = 0.0126 (III). Basic structural units of these crystals are [(UO2)2C2O4(XO4)2(NCS)2]4− chains, which belong to the crystallochemical group A 2 K 02 B 22 M 21 (A = UO22+, K 02 = C2O2−4, B 2 = SO42− or SeO42−, M 1 = NCS) of uranyl complexes. Uranium-containing chains are connected into a 3D framework via a system of electrostatic interactions with potassium or rubidium cations from outer spheres. Original Russian Text ? I.V. Medrish, E.V. Peresypkina, A.V. Virovets, L.B. Serezhkina, 2008, published in Kristallografiya, 2008, Vol. 53, No. 3, pp. 495–498.  相似文献   

11.
The crystal structures of three Pd(II) compounds with diamine tetracarboxylates in different protonation states are determined, namely, [Pd(H2 Cdta)] · H2O (I), [Pd(H3 EdtpCl] · 2H2O (II), and (H6 Edtp)[PdCl4] · 4H2O (III) (R 1 = 0.0230, 0.0313, and 0.0277 for 3040, 3377, and 3809 reflections with I > 2σ(I) for I–III, respectively). Crystals I and II are built of neutral complexes [Pd(H2 Cdta)] and [Pd(H3 Edtp)Cl], respectively, and crystallization water molecules. Crystal III consists of [PdCl4]2− anionic complexes, H6 Edtp 2+ cations, and water molecules. In I, one of the protonated acetate groups of the H2 Cdta 2− ligand forms a very weak additional Pd-O bond [2.968(2) Å] over the 2N + 2O coordination square. In II and III, the protonated propionate groups of the H3 Edtp ligand and the H6 Edtp 2+ cation are not involved in Pd coordination and the coordination squares consist of the 2N + O + Cl and 4Cl atoms, respectively. __________ Translated from Kristallografiya, Vol. 48, No. 2, 2003, pp. 278–282. Original Russian Text Copyright ? 2003 by Polyakova, Poznyak, Sergienko.  相似文献   

12.
The reaction of the pincer diphosphine ligand 4,6-bis(diphenylphosphinomethyl)-m-xylene (dppx) with the metal cluster compounds PhCCo3(CO)9 and Ru66-C)(CO)17 has been explored. Both clusters react with dppx to afford the simple substitution products [PhCCo3(CO)8]2(dppx) and [Ru66-C)(CO)16]2(dppx), where two cluster units are tethered by the pincer ligand. The molecular structures of the title products and the 2:1 cluster-pincer ligand stoichiometry have been established by X-ray crystallography. The stability of [PhCCo3(CO)8]2(dppx) and [Ru66-C)(CO)16]2(dppx) has been investigated under gentle thermolysis conditions (ca. 55–65°C). Both dppx-substituted clusters are unstable with [PhCCo3(CO)8]2(dppx) decomposing and [Ru66-C)(CO)16]2(dppx) transforming into the diphosphine-bridged cluster Ru66-C)(CO)15(μ-dppx) as the major observable product. The identity of the latter cluster has been ascertained by IR and NMR spectroscopies and mass spectrometry.  相似文献   

13.
A new organic-inorganic hybrid γ-octamolybdate complex, (NH4)4[(C3H7NO)2Mo8O26]·2CH3CH2OH·2H2O was synthesized from the mixture of ethanol, DMF, 4-aminobenzoic acid, (NH4)6Mo7O24·4H2O, HCl and H2O. The structure was determined by X-ray crystallography. It crystallizes in monoclinic P21/n space group with the crystal cell parameters of a = 8.8825(4), b = 21.1608(10), c = 11.1343(6) ?, β = 104.7720(10)°, V = 2023.64(17) ?3 and Z = 2. The crystal X-ray analysis shows that two DMF molecules are bound to γ-octamolybdate anion. The molecular structure is stabilized by the complex hydrogen bonding.  相似文献   

14.
The crystal structure of a new synthetic aluminophosphate {[Rb1.94(H2O,OH)3.84](H2O)0.1}{Al4(OH)4[PO4]3} synthesized under mild hydrothermal conditions (T = 280°C, P = 100 atm) in the Rb2O-Al2O3-P2O5-H2O system is determined using X-ray diffraction (Stoe IPDS diffractometer, λMoK α, graphite monochromator, 2θmax = 64.33°, R = 0.032 for 312 reflections). The main crystal data are as follows: a = 7.4931(6) ?, space group P 3m, Z = 1, and ρcalcd = 2.76 g/cm3. It is shown that the synthesized compound belongs to the pharmacosiderite structure type with a characteristic mixed open microporous framework composed of octahedra and tetrahedra. A comparative crystal chemical analysis of related phases is performed, and the chemical compositions of promising absorbents, i.e., hypothetical compounds potentially possible in the structure type under consideration, are proposed. It is established that pharmacosiderite and rhodizite are homeotypic to each other. Original Russian Text ? O.V. Yakubovich, W. Massa, O.V. Dimitrova, 2008, published in Kristallografiya, 2008, Vol. 53, No. 3, pp. 442–449.  相似文献   

15.
The X-ray crystal structure of propargylammonium hexafluorosilicate, 2(C3H6N)+ (SiF6)2−, is determined. The SiF6 anion is involved in N−H...F and C−H...F interactions with eight surrounding cations. This involves two-three-and four-center N−H...F hydrogen bonds, and additional C−H...F interactions with C...F distances down to 2.963(6) ?. The alkynyl C−H donors form only C−H...F interactions of unfavorable geometries.  相似文献   

16.
Two 1D polymeric complex, [Cu(CBC)2(Dabco)(H2O)] n (1) and [Ag2(HBC)2(Dabco)] n (2) have been synthesized and characterized by X-ray single crystal analysis, where CBCH is p-chlorobenzoic acid, HBCH 2 is 2-hydroxybenzoic acid and Dabco is 1,4-diazabicyclo[2.2.2]octane. Complex 1 has been obtained in high yield by hydrothermal synthesis from CuO and CBCH and Dabco, and complex 2 has been obtain by evaporation of the solvent from silver salicylate and Dabco, 1 crystallizes in the orthorhombic space group Pmn2 1 with a = 24.3310(5) ?, b = 6.9050(6) ?, c = 5.9980(5) ?, Z = 2, V = 1007.70(4) ?3 and Dx = 1.657 g cm−3, 2 crystallizes in the monoclinic space group P2 1 /m with a = 10.292(3) ?, b = 6.913(2) ?, c = 14.417(4) ?, β = 95.660(5), Z = 2, V = 1020.8(5) ?3 and Dx = 1.959 g cm−3. The final R value is 0.0302 for 1323 measured reflections for 1 and the final R value is 0.0684 for 1545 measured reflections for 2. The atomic arrangement is built by infinite one-dimensional polymeric chain in both complexes. These chains are cross-linked by hydrogen bonds involving the coordinated water molecules to form a two-dimensional framework in complex 1.  相似文献   

17.
A combinatorial and topological analysis of Li19Na8Ba15 (hP842, a = 20 ?, c = 93 ?, V = 33552 ?3, P $ \bar 3 $ \bar 3 ) has been performed using computer methods (the TOPOS program package). Two types of crystal-forming quasi-spherical nanoclusters about 20 ? in diameter with internal Friauf polyhedra (A-172) and icosahedra (B-137) have been established by the complete decomposition of the 3D factor graph of the structure into cluster substructures. Each type of nanoclusters forms close-packed 2D layers 36, which alternate along the c axis. The B-137 and A-172 nanoclusters are composed of three layers and have shell compositions (1 + 12 + 32 + 92) and (1 + 16 + 59 + 103) with local symmetries 3 and $ \bar 3 $ \bar 3 , respectively; they were revealed for the first time in crystal structures as cluster precursors. The icosahedral B-137 nanocluster contains a 104-atom quasicrystal approximant (Samson cluster).  相似文献   

18.
4-(Piperidyl-1)-2-phenylpyrido[2,3-a]anthraquinonium-7,12 hexachlorodicuprate(II) and 4-(piperidyl-1)-2-phenylpyrido[2,3-a]anthraquinonium-7,12 dibromocuprate(I) are isolated in the crystalline state and investigated using X-ray diffraction. It is established that the Cu(II) cation is reduced to the Cu(I) cation during the synthesis of anionic bromocuprate complexes in the presence of hydrobromic acid. The spectral characteristics of the prepared compounds are discussed. Original Russian Text ? O.V. Kovalchukova, A.I. Stash, S.B. Strashnova, V.K. Belsky, Tran Than Tung, B.E. Zaĭtsev, 2008, published in Kristallografiya, 2008, Vol. 53, No. 3, pp. 484–487.  相似文献   

19.
Two imidazolidin ruthenium complexes, [RuCl2{[N-(2,4,6-trimethyl-benzyl)-N-(n-butyl)]-imidazolidin-2-ylidene}], 1, and [RuCl2{[N-(2,4,6-trimethyl-benzyl)-N-(2-methoxyethyl)]-imidazolidin-2-ylidene}], 2, have been synthesised and their crystal structures have been determined from single crystal X-ray diffraction data. Compound 1 is monoclinic, of space group C2/c with a = 18.466(4) Å, b = 14.816(3) Å, c = 15.413(3) Å, β = 118.067(2), and V = 3720.9(12) Å3 with Z = 8 for dcalc = 1.536 g/cm3. Compound 2 is monoclinic, of space group P21/c with a = 8.1800(5) Å, b = 14.344(8) Å, c = 14.809(9), β = 91.604(10), and V = 1736.7(18) Å3 with Z = 4 for dcalc = 1.653 g/cm3. In each complex the ligand functions as an arene and carbene, occupying four coordination sites. The two chlorines in each compound complete a distorted octahedron.  相似文献   

20.
Treatment of [Os3(CO)12] with indole in presence of a methanolic solution of Me3NO⋅2H2O at 60C afforded the previously reported compounds [(μ-H)Os3(CO)10(μ-OMe)] 2, [(μ-H)Os3(CO)10(μ-OH)] 3 and [Os3(CO)10(μ-OH)(μ-OMeCO)] 4 in 10, 5 and 20% yields, respectively. The reaction of [Os3(CO)10(MeCN)2] with indole at room temperature gave [(μ-H)Os3(CO)10(μ-1,2-η2-NC8H6)] 5 in 40% yield. Compounds 4 and 5 have been characterized by single crystal X-ray diffraction studies. Compound 4 crystallizes in the monoclinic space group P2(1)/c with a = 23.1239(3), b = 9.8087(4), c = 16.9017(6) ?, β = 92.6998(14), Z = 8 and V = 3829.3(2) ?3 and 5 crystallizes in the monoclinic space group P2(1)/c with a = 9.009(3), b = 9.764(4), c = 24.906(6) ?, β = 93.452(14), Z = 4 and V = 2186.9(13) ?3. Compound 4 consists of an open cluster of three osmium atoms with the hydroxy and methoxycarbonyl ligands bridging the open Os–Os edge. Compound 5 consists of an isosceles triangle of osmium atoms with one elongated Os–Os edge which is bridged by the hydride and the indolyl ligands.  相似文献   

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