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1.
Crystals of new rare earth borates of the composition Ln[B6O9 (OH)3] (Ln = Sm-Lu), sp. gr. R3c are synthesized under hydrothermal conditions. Their crystal structures are determined on single crystals with Ln = Ho, Gd without preliminary determination of their chemical formulas. The polar anionic framework of the crystals consists of BO3 triangles and BO4 tetrahedra and has wide channels along the threefold axis of the structure, which are similar to the channels along the a, b, and c axes in cubic Li4[B7O12]Cl boracite with Li conductivity. Rare earth atoms are arranged in the structure over the cubic F pseudolattice, whereas the analogous positions in Li boracites are filled with Cl anions. The squared optical nonlinearity of the new crystals is comparable with the nonlinearity of quartz, whereas the electrical conductivity in borates at 300°C exceeds 10−6 S/cm. __________ Translated from Kristallografiya, Vol. 49, No. 4, 2004, pp. 681–691. Original Russian Text Copyright ? 2004 by Belokoneva, Ivanova, Stefanovich, Dimitrova, Kurazhkovskaya.  相似文献   

2.
The reactions in the C60-(TiCl4 + Br2) system have been performed in ampoules at elevated temperatures. The molecular structure of the fullerene halides (C60Cl5)2, C60 X 6, C60 X 8, and C60 X 24 (X = Cl, Br) has been determined and refined using single-crystal X-ray diffraction. It has been established that an increase in the bromine concentration results in an increase in the number of halogen atoms attached to the fullerene cage and in an increase in the relative fraction of bromine atoms in mixed halogen derivatives from almost pure chlorides (C60Cl5)2 and C60Cl6 to halides C60 X 8 and C60 X 24 with a high relative bromine content. Original Russian Text ? S.I. Troyanov, A.V. Burtsev, E. Kemnitz, 2009, published in Kristallografiya, 2009, Vol. 54, No. 2, pp. 268–275.  相似文献   

3.
Dark red crystals of bis[trans-dinitrobis(ethylenediamine)cobalt(III)] dichromate, [trans-Co(en)2(NO2)2]2(Cr2O7) have been obtained by slowly allowing to mix the solutions of potassium dichromate and trans-dinitrobis(ethylenediamine)cobalt(III) nitrate in 1:2 molar ratio in aqueous medium. Elemental analyses and spectroscopic techniques (IR, UV/visible, 1H and 13C NMR) were used for characterizing the complex salt. The complex salt crystallizes in the orthorhombic space group Fdd2 with unit cell dimensions a = 24.778(2) ?, b = 30.457(2) ?, c = 6.5364(5) ?, Z = 8, V = 4932.8(7) ?3, R1 = 0.0617 and wR2 = 0.1518. X-ray structure determination revealed an ionic structure consisting of cationic cobaltammine [trans-Co(en)2(NO2)2]NO3 and dichromate anion. It is the first crystal structure of this cation with a dianion.  相似文献   

4.
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   

5.
Single crystals of the compound (NH4)3[UO2(CH3COO)3]2[UO2(CH3COO)(NCS)2(H2O)] (I) are synthesized, and their structure is investigated using X-ray diffraction. Compound I crystallizes in the monoclinic system with the unit cell parameters a = 18.3414(6) ?, b = 16.3858(7) ?, c = 12.4183(5) ?, β = 92.992(1)°, space group C2/c, Z = 4, V = 3727.1(3) ?3, and R = 0.0253. The uranium-containing structural units of crystals I are mononuclear complexes of two types with an island structure, i.e., the [UO2(CH3COO)3] anionic complexes belonging to the crystal-chemical group (AB 301 = UO22+, B 01 = CH3COO) of the uranyl complexes and the [UO2(CH3COO)(NCS)2(H2O)] anionic complexes belonging to the crystal-chemical group AB 01M31 (A = UO22+, B 01 = CH3COO, M 1 = NCS or H2O).  相似文献   

6.
The single crystal structure of NH4[UO2(CH3COO)3] (I), K[UO2(CH3COO)3] (II), and Cs[UO2(CH3COO)3] (III) is studied by X-ray diffraction. I and II crystallize in the tetragonal crystal system. The crystal data are as follows: a = 13.6985(3) and c = 27.5678(14) ?, V = 5173.1(3) ?3, space group I41/a, Z = 16, and R = 0.023 for I; a = 13.8890(5) and c = 26.0839(18) ?, V = 5031.7(4) ?3, space group I41/a, Z = 16, and R = 0.037 for II. Crystals III are orthorhombic, a = 18.176(2), b = 13.119(2), and c = 22.088(4) ?, V = 5267(1)?3, space group Pbca, Z = 16, and R = 0.0424. In structures I–III, the uranium-containing structural units are represented by discrete mononuclear [UO2(CH3COO)3] groups, which belong to the AB 301 (A = UO22+, B 01=CH3COO) crystal chemical group of uranyl complexes.  相似文献   

7.
Thin films (1-10 μm thickness) of nanocomposites (NC) based on organic coordinated compound (OCC) Eu(TTA)2(Phen3PO)2NO3 (where TTA is thenoyltrifluoroacetonate (C8H5F3O2S), Phen - 1,10-phenanthroline (C12H8N2)) and polymer - polyvinylpyrrolidone ((C6H9NO)n) (PVP)) were obtained by chemical methods. NC were characterized by measurements of optical transmission, and photoluminescence (PL) at different concentrations of Eu(TTA)2(Phen3PO)2NO3 in NC. Using the optical transmission spectra, the characteristic parameters of NC such as threshold of absorbance and the position of the absorption edge on the concentration of the OOC in NC, etc., were determined. The light displacement of threshold absorption to infrared region was observed with increasing of concentration of coordinated material in NC. It was established that the excitation spectrum at which the photoluminescence in NC take place cover the range of wavelength from 200 to 410 nm. The PL of nanocomposites was detected as specific for internal transitions 4f-4f of the Eu3+ ion 5D0  7Fi (i = 0,1,2,3 and 4) centred at 537, 580, 615, 650 and 702 nm, respectively at T = 300 K. The dominant PL was observed at 615 nm and its halfwidth is less than 10 nm. The intensity of photoluminescence at 615 nm of NC is 2 times higher than the value of intensity of PL of Eu(TTA)2(Phen3PO)2NO3 powders at equal conditions of excitation.  相似文献   

8.
The crystal structure of the [La(DMSO)6(H2O)PW12O40] · C2H5OH complex (I) (where DMSO is dimethyl sulfoxide) is determined by X-ray diffraction analysis. The coordination polyhedron of the La atom is a distorted tricapped trigonal prism in which two cap sites are occupied by oxygen atoms of the heteropolyanions. For these atoms, the La-O distances [2.760(9) and 2.801(9) Å] are considerably longer than the other distances [ranging from 2.441(10) to 2.569(10) Å] in the environment of the La atom. __________ Translated from Kristallografiya, Vol. 47, No. 6, 2002, pp. 1039–1041. Original Russian Text Copyright ? 2002 by Grigoriev, Shirokova, Fedoseev, Den Auwer.  相似文献   

9.
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   

10.
A complex of copper(II) with the diethylenetriaminemonopripionate ligand [Cu2(4-Dtmp)2](ClO4)2 (I) is synthesized and characterized using X-ray diffraction. The crystals of compound I are monoclinic, a = 7.740(2) Å, b = 19.199(3) Å, c = 8.449(2) Å, β = 91.61(2)°, Z = 2, and space group P21/n. The structural units of crystal I are centrosymmetric dimeric cations and statistically disordered ClO 4 anions. In the cation, the copper atom is coordinated by three N atoms [mean Cu-N, 2.01(1) Å] and two O atoms [Cu-O, 2.134(6) Å and 1.958(7) Å] of the pentadentate bridging-chelate Dtmp ligand, which occupy vertices of the trigonal bipyramid. The binuclear cations are linked via centrosymmetric pairs of hydrogen bonds into ribbons aligned parallel to the a axis of the crystal. The ClO 4 anions form columns in the same direction. In the crystal, the cationic ribbons and anionic columns alternate in a chessboard fashion. __________ Translated from Kristallografiya, Vol. 50, No. 3, 2005, pp. 450–454. Original Russian Text Copyright ? 2005 by Antsyshkina, Sadikov, Poznyak, Sergienko.  相似文献   

11.
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   

12.
Single crystals of PbUO2(CH3COO)4(H2O)3 have been investigated by X-ray diffraction (R = 0.029 for 3175 reflections). The structure of this compound is formed by [Pb(CH3COO)(H2O)3]+ chains, which are oriented along the [100] axis and limited by one-core complexes [UO2(CH3COO)3]. The coordination numbers of the Pb(II) and U(VI) atoms are 8, and the coordination polyhedron of uranium is a hexagonal bipyramid whose vertices contain oxygen atoms of three bidentate cyclic acetate groups and the uranyl group. Taking into account the different crystallographic roles of acetate ions, the crystal-chemical formula of [PbUO2(CH3COO)4(H2O)3] chains can be written as AAB 21 B 11(B 01)2 M 31, where A = Pb; A′ = UO22+; M 1 = H2O; and B 21, B 11, and B 01 are CH3COO groups.  相似文献   

13.
Single crystals of rare earth (RE) selenates of the compositions Nd(HSeO4)3, Sm(HSeO4)3, and Nd2(SeO4)3 · 5H2O are synthesized and studied by X-ray diffraction analysis at T = 297 and 180 K. It is established that Nd and Sm hydrogen selenates are isostructural to one another and to the corresponding hydrogen sulfates. Neodymium selenate pentahydrate is not isostructural to the analogous RE sulfates, although their structural motifs are similar. __________ Translated from Kristallografiya, Vol. 49, No. 5, 2004, pp. 835–840. Original Russian Text Copyright ? 2004 by Zakharov, Troyanov, Kemnitz.  相似文献   

14.

Abstract  

Two copper coordination polymers [CuI(bipy)1/2Cl] n (1) and {[(CuII)4(phen)4(SSA)2Cl2] (H2O)2(DMF)2} n (2)(bipy = 4,4′-bipyridine, phen = 1,10-phenanthroline, H3SSA = 5-sulfosalicylic acid, DMF = N,N-dimethylformamide) have been prepared and characterized by X-ray diffraction, elemental analysis, IR spectrum and 2 was also studied by cyclic voltammetric method. X-ray analysis indicates that both of them have Cu2Cl2 bridging subunit. Complex 1 is a two dimensional network structure. While 2 shows a one dimensional zigzag chain. Electrochemistry studies reveal that complex 2 undergo a quasi reversible one-electron metal-centered redox process at E 1/2 = +0.062 V.  相似文献   

15.
Barite-type α-BaBeF4 (a = 8.8594(3), b =5.3265(2), c = 7.0493(2) Å, Pnma (No. 62)) and Ba(BeF4)0.535(7)(SO4)0.465(7) (a = 8.8657(2), b = 5.3902(2), c = 7.1007(2) Å, Pnma (No. 62)) were prepared by precipitation from aqueous solutions and their structures refined from laboratory X-ray powder diffraction data. In the case of α-BaBeF4 it was possible to identify the light atom Be on a difference Fourier map and to refine its positional parameters in the presence of a heavy atom (Ba). Both phases contain almost ideal isolated BX42− tetrahedra (B = Be, Be/S and X = F, F/O) together with Ba, that is 12-fold coordinated by X. The plausibility of the resulting structures was proved with the help of the bond valence model. For both compounds no phase transitions were found up to 550C.  相似文献   

16.
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   

17.
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   

18.
On the basis of the physicochemical analysis of the solubility phase diagrams for the Me 2SO4-NiSO4-H2O ternary systems (Me = Na, Rb, or Cs), the optimum concentration and temperature conditions for the crystallization of the Me 2Ni(SO4)2 · nH2O solid phases were found. Techniques for growth of single crystals of these binary salts have been developed. Such techniques allow application of mother liquors containing hydrates or anhydrous sulfates of Na, Rb, Cs, and Ni as raw materials. Na2Ni(SO4)2 · 4H2O, Rb2Ni(SO4)2 · 6H2O, and Cs2Ni(SO4)2 · 6H2O single crystals (28–34) × (8–13) × (5–10) mm3 in size have been grown from aqueous solutions in the dynamic regime. Original Russian Text ? L.V. Soboleva, 2007, published in Kristallografiya, 2007, Vol. 52, No. 6, pp. 1141–1144.  相似文献   

19.
The title compound, Cu3(Bipy)2(L1)2(L2)2⋅4H2O, was synthesized in the methanol solution of Bipy and Cu(II) in the presence of 1-((2-sulfonate-ethylimino)-methyl)-2-naphthol (L1), which was condensation compound of taurine and 2-hydroxy-1-naphthaldehyde. This complex crystallized in the space group P-1 with a = 9.825(2) ?, b = 12.626(2) ?, c = 14.342(3) ?, α = 90.29(1), β = 100.67(1), γ = 101.67(2), and Z = 2. In the trinuclear Cu(II) complex, there are two type Cu atoms which have square and square pyramid geometries, respectively. The Cu–N distances vary from 1.965(3) to 2.000(4) ?, while the Cu–O distances are between 1.896(3) and 2.337(4) ?.  相似文献   

20.
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