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1.
Li(VO2)3(TeO3)2     
The title compound, lithium tris[dioxidovanadium(V)] bis[trioxidotellurium(IV)], contains chains of edge‐sharing distorted VO6 octahedra. The pyramidal TeO3 groups crosslink the chains into sheets. Finally, an Li+ cation adopting an unusual capped trigonal–bipyramidal LiO6 geometry bridges the layers to complete a three‐dimensional structure.  相似文献   

2.
(CF3)2PAsH2 and (CF3)2AsAsH2 (CF3)2PAsH2 is obtained in yields between 30 and 60% according to eq. (1) (CF3)2AsAsH2 is formed by the analogous reaction with (CF3)2AsI, but is not sufficiently stable to be isolated. Both compounds are decomposed according to eq. (2) (CF3)2PAsH2 can be studied in solution below ?40°C; it is characterized by molar mass determination and by its n.m.r. spectra (1H, 19F, 31P). Reactions with polar [HBr, (CH3)2AsH, (CH3)2PN(CH3)2] and nonpolar [Br2, As2(CH3)4] reagents proceed by cleavage of the P? As bond.  相似文献   

3.
The reaction of (CH3)2AsJ and AgN3 yields (CH3)2AsN3; a colourless liquid (b. p. 136°C) which dissolves as a monomeric in benzene. (CH3)2BiN3 is precipitated in form of colourless needles (dec. temp. 150°C) from an etherical solution of Bi(CH3)3 and HN3. According to its vibrational and mass spectra the molecules are not associated although the (CH3)2BiN3 is not soluble; dipole association of this polar molecules is assumed for the crystal structure. (CH3)2TlN3 can be obtained from TI(CH3)3 and ClN3 as well as from (CH3)2TlOH and HN3 in form of colourless needles and leaves (dec. temp. 245°C). According to its vibrational spectra it has an ionic structure, (CH3? Tl? CH3)+N?3.  相似文献   

4.
RbLi2Ga2(BO3)3     
The structure of rubidium dilithium digallium tris­(borate), RbLi2Ga2(BO3)3, contains two‐dimensional sheets of open‐branched rings of GaO4 tetrahedra and planar BO3 triangles that are joined by LiO4 tetrahedra to form a three‐dimensional framework. Ten‐coordinate Rb atoms lie on twofold axes and occupy channels within the framework that extend along the b axis.  相似文献   

5.
Two novel isopropylamine‐templated uranyl chromates, [(CH3)2CHNH3]3[(UO2)3(CrO4)2O(OH)3] ( 1 ) and [(CH3)2CHNH3]2[(UO2)2(CrO4)3(H2O)] ( 2 ) were prepared by hydrothermal method at 100 °C. The compounds were characterized by electron microprobe analysis and X‐ray diffraction crystal structure analysis [ 1 : trigonal, P31m, a = 9.646(4), c = 8.469(4) Å, V = 682.4(5) Å3; 2 : monoclinic, P21/c, a = 11.309(3), b = 11.465(3), c = 17.055(5) Å, β = 99.150(6)°, V = 2183.2(11) Å3]. The structure of 1 is based upon trimers of uranyl bipyramids interlinked by CrO4 tetrahedra to form [(UO2)3(CrO4)2O(OH)3]3– layers, whereas, in the structure of 2 , UO7 and UO6(H2O) pentagonal bipyramids are linked through CrO4 tetrahedra into the [(UO2)2(CrO4)3(H2O)]2– layers. The structures show many similarities to related uranyl selenate compounds, thus providing additional data on similarities and differences between uranyl sulfates, chromates, selenates, and molybdates.  相似文献   

6.
7.
Perfluorosalkyl Tellurium Compounds: Oxidation of (CF3)2Te; Preparations and Properties of (CF3)2TeCl2, (CF3)2TeBr2, (CF3)2Te(ONO2)2, and (CF3)2TeO From the oxidation of (CF3)2Te with Cl2, Br2, O2, and ClONO2 the new trifluoromethyl tellurium compounds (CF3)2TeCl2, (CF3)2TeBr2, (CF3)2TeO, and (CF3)2Te(ONO2)2 are prepared. The 19F, 13C and 125Te n.m.r. spectra, the vibrational and mass spectra as well as the chemical properties of these compounds are described. By variation of the reaction conditions CF3TeCl3 and CF3TeBr3 are also formed. It has not been possible to isolate (CF3)2TeI2, but there is some evidence that it is formed as an intermediate. (CF3)2Te reacts with ozone to a very unstable compound, which decomposes at low temperature.  相似文献   

8.
Crystals of PbCu3(OH)(NO3)(SeO3)3·1/2H2O [a=7.761(3)Å,b=9.478(4)Å,c=9.514(4)Å, =66.94(2)°, =69.83(2)°, =81.83(2)°, space group P ,Z=2] and Pb2Cu3O2(NO3)2(SeO3)2 [a=5.884(2)Å,b=12.186(3)Å,c=19.371(4)Å, space group Cmc21,Z=4] were synthesized under hydrothermal conditions. Their crystal structures were refined with three-dimensional X-ray data toR w=0.033 resp. 0.055. In PbCu3(OH)(NO3)(SeO3)3·1/2H2O the Cu atoms are [4+1] and [4+2] coordinated and via SeO3 groups a three-dimensional atomic arrangement is built up. In Pb2Cu3O2(NO3)2(SeO3)2 there are sheets, which are connected only via Pb-O bonds ranging from 2.98 Å to 3.16 Å.
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9.
The ruthenium(II) complex used as a catalyst in reactions of alcohols and Et3SiH proved to be the dimer [(CH3)3PRu(CO)2Cl2]2 and not the complex [(CH3)3P]2 Ru(CO)2Cl2. Both complexes were prepared, characterized and their catalytic properties were compared.  相似文献   

10.
The infrared spectra of the title compounds are reported and discussed. The influence of the peroxide groups on the bond properties of the other ligands and some characteristics of the metal—peroxide interactions are analyzed.  相似文献   

11.
12.
Xenon trioxide (XeO3) forms adducts with triphenylphosphine oxide, dimethylsulfoxide, pyridine-N-oxide, and acetone by coordination of the ligand oxygen atoms to the XeVI atom of XeO3. The crystalline adducts were characterized by low-temperature, single-crystal X-ray diffraction, and Raman spectroscopy. Unlike solid XeO3, which detonates when mechanically or thermally shocked, solid (C5H5NO)3(XeO3)2, [(C6H5)3PO]2XeO3, and [(CH3)2SO]3(XeO3)2 are insensitive to mechanical shock. The [(CH3)2SO]3(XeO3)2 adduct slowly decomposes over several days to (CH3)2SO2, Xe, and O2. All three complexes undergo rapid deflagration when ignited by a flame. Both [(C6H5)3PO]2XeO3 and (C5H5NO)3(XeO3)2 are room-temperature stable and the [(CH3)2CO]3XeO3 complex dissociates at room temperature to form a stable solution of XeO3 in acetone. The xenon coordination sphere of [(C6H5)3PO]2XeO3, a distorted square-pyramid, provides the first example of a five-coordinate XeO3 complex with only two Xe- - -O adduct bonds. The xenon coordination spheres of the remaining adducts are distorted octahedra, comprised of three Xe- - -O secondary bonds that are approximately trans to the primary Xe−O bonds of XeO3. Quantum-chemical calculations were used to assess the nature of the Xe- - -O adduct bonds, which are described as predominantly electrostatic bonds between the nucleophilic oxygen atoms of the bases and the σ-holes of the electrophilic xenon atoms.  相似文献   

13.
The experimental results obtained for the specific molar heat capacity of the tellurites Yb2(TeO3)3, Dy2(TeO3)3 and Er2(TeO3)3 are processed by the least squares method. The temperature dependence of the specific molar heat capacity derived is used to determine the thermodynamic properties: entropy ( \UpdeltaTT Sm0 ), \left( {\Updelta_{T\prime }^{T} S_{m}^{0} } \right), enthalpy ( \UpdeltaTT Hm0 ) \left( {\Updelta_{T\prime }^{T} H_{m}^{0} } \right) and Gibbs function ( \UpdeltaTT Gm0 ) \left( {\Updelta_{T\prime }^{T} G_{m}^{0} } \right) of the tellurites Yb2(TeO3)3, Dy2(TeO3)3 and Er2(TeO3)3.  相似文献   

14.
The title compound, lithium trimanganese bis­[trioxo­selenate(IV)] hexa­kis[hydrogentrioxoselenate(IV)], is built up from a vertex‐sharing network of distorted MnIIIO6 octa­hedra, SeO3 and HSeO3 pyramids and unusual Li(OH)6 octa­hedra, resulting in a dense three‐dimensional structure. Mn, Li and one Se atom have site symmetries of , , and 3, respectively. An O—H⋯O hydrogen bond helps to establish the crystal packing.  相似文献   

15.
16.
The title compounds have been respectively synthesized by solution process and solvothermal reaction, and their crystal structures were determined by X-ray diffraction method. For (CH3CH2CH2CH2NH3)6(BiI6)(I)2I3 1, it crystallizes in tficlinic, space group P1^- with Mr = 2049.76, a = 8.5719(1), b = 11.7461(3), c = 15.700(1)A, V = 1451.4(1)A^3, Z = 1, Dc = 2.345 g/cm^3, F(000) = 924, μ(MoKα) = 8.907 mm^-1, T = 293(2) K, the final R = 0.0655 and wR = 0.0804 for 2399 observed reflections with I 〉 2σ(I). For (NH3CH2CH2NH3)2Bi2I10 2, it crystallizes in monoclinic, space group P21/n with Mr= 1811.20, a = 8.434(4), b = 13.862(6), c = 13.362(6)A, V = 1499.9(12)A^3, Z = 2, Dc = 4.010 g/cm^3, F(000) = 1536,μ(MoKα) = 22.007 mm^-1, T = 293(2) K, the final R = 0.0584 and wR = 0.1451 for 1798 observed reflections with I 〉 2σ(I). The structures of 1 and 2 contain halobismuthate monomer and dimers, respectively. It is noteworthy that the dimers and their organic counters in 2 connect each other by N…I hydrogen bonds to form a layered structure, and the electrostatic interactions and crystal packing forces between layers give rise to the packing of the crystal. The optical absorption spectra of 1 and 2 reveal the appearance of sharp optical gaps of 2.13 and 2.01 eV, respectively.  相似文献   

17.
Formation and Structure of the Cyclophosphanes P4(CMe3)2[P(CMe3)2]2 and P4(SiMe3)2[P(CMe3)2]2 n-Triphosphanes showing a SiMe3 and a Cl substituent at the atoms P1 and P2, like (Me3C)2P? P(SiMe3)? P(CMe3)Cl 3 or (Me3C)2P? P(Cl)? P(SiMe3)2 4 are stable only at temperatures below ?30°C. Above this temperature these compounds lose Me3SiCl, thus forming cyclotetraphosphanes, P4(CMe3)2[P(CMe3)2]2 1 out of 3 , P4(SiMe3)2[P(SiMe3)2]2 2a (cis) and 2b (trans) out of 4 . The formation of 1 proceeds via (Me3C)2P? P?PCMe3 5 as intermediate compound, which after addition to cyclopentadiene to give the Diels-Alder-adduct 6 (exo and endo isomers) was isolated. 6 generates 5 , which then forms the dimer compound 1 . Likewise (Me3C)2P? P?P-SiMe3 8 (as proven by the adduct 7 ) is formed out of 4 , leading to 2a (cis) and 2b (trans). Compound 1 is also formed out of the iso-tetraphosphane P[P(CMe3)2]2[P(CMe3)Cl] 9 , which loses P(CMe3)2Cl when warmed to a temperature of 20°C. 1 crystallizes monoclinically in the space group P21/a (no. 14); a = 1762.0(15) pm; b = 1687.2(18) pm; c = 1170.5(9) pm; β = 109.18(5)° and Z = 4 formula units in the elementary cell. The molecule possesses E conformation. The central four-membered ring is puckered (approx. symmetry 4 2m; dihedral angle 47.4°), thus bringing the substituents into a quasi equatorial position and the nonbonding electron pairs into a quasi axial position. The bond lengths in the four-membered ring of 1 (d (P? P) = 222.9 pm) are only slightly longer than the exocyclic bonds (221.8 pm). The endocyclic bond angles \documentclass{article}\pagestyle{empty}\begin{document}$ \bar \beta $\end{document}(P/P/P) are 85.0°, the torsion angles are ±33° and d (P? C) = 189.7 pm.  相似文献   

18.
19.
Summary Single crystal X-ray data of the hydrothermally grown new phase Li2Cu3(SeO3)2(SeO4)2 were measured with a four-circle diffractometer up to sin /=0.81 Å–1 [I2/a,Z=4,V=1175.5 Å3,a=16.293(6),b=5.007(2),c=14.448(6) Å, = 94.21(1)°]. The structure was determined by direct and Fourier methods and refined toR=0.034,R w =0.027 for 2 086 independent reflections.Cu(1)[4+1]O5 forms a tetragonal pyramid, Cu(2)[4 + 2]O6 is a strongly elongated octahedron. The Li atom is surrounded by four O atoms forming a distorted tetrahedron. Se(IV)O3 and Se(VI)O4 groups are in accordance to literature, mean Se-O bond lengths are 1.714 and 1.644 Å.
Die Kristallstruktur von Li2Cu3(SeO3)2(SeO4)2
Zusammenfassung Einkristall-Röntgendaten der hydrothermal gezüchteten neuen Phase Li2Cu3(SeO3)2(SeO4)2 wurden mit einem Vierkreisdiffraktometer im Bereich bis zu sin /=0.81 Å–1 gemessen [I2/a,Z=4,V=1175.5 Å3,a=16.293(6),b=5.007(2),c=14.448(6) Å, =94.21(1)°]. Die Kristallstruktur wurde mittels direkter und Fourier-Methoden bestimmt und für 2 086 unabhängige Reflexe zuR=0.034,R w =0.027 verfeinert.Cu(1)[4+1]O5 bildet eine tetragonale Pyramide, Cu(2)[4+2]O6 ist ein stark verlängertes Oktaeder. Das Li-Atom ist von vier O-Atomen in Gestalt eines verzerrten Tetraeders umgeben. Die Se(IV)O3-und Se(VI)O4-Gruppen entsprechen der Literatur, die mittleren Se-O-Abstände betragen 1.714 und 1.644 Å.
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20.
The structure of the title compound, which has been synthesized by evaporation at 294 K, consists of centrosymmetric uranyl hexagonal bipyramids that share opposite equatorial edges with two nitrate triangles, resulting in two distinct finite clusters of composition [(UO2)(H2O)2(NO3)2]. There are two unique symmetrically independent UVI positions and two unique nitrate groups.  相似文献   

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