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1.
《结构化学》1993,(4)
<正> Complex Cp'2 ErCl(Cp'=2-methoxyethylcyelopentadienyl)(I)has been synthesized by the reaction of Cp' Na and ErCl3 in THF It crystallizes in space group Pnma with a=12.269(0),b=11.742(6),c=11.197(2)A,V=1613.1A3,Dc=1.849 g/cm3,Z=4,A=0.71073 A,μ(MoKa)=54.38 cm-1,F(000)=876,R=0.043,Rw=0.046.The Er atom is formally nine-coordinated with a pseudo-trigonal bipyramidal geometry with the "equatorial" plane composed of the Er atom,the Cl atom and the centers(1)and(2)of the two Cp rings(Cp=cy-clopentadienyl).The molecule is located at the crystallographic mirror plane through the atom C(3),C(4),C(S),Er,O(1)and C(6).The atom Cl and the atoms of Cp'(2)(except C(16)and C(16'))are disordered with an occupancy of 0.5 each. 相似文献
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J. C. J. Bart I. W. Bassi M. Calcaterra 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3):347-352
Abstract The molecular and crystal structure of bis(triphenylbenzylphosphonium)tetrabromocadmate has been determined by x-ray diffractometer data. Crystals are triclinic, space-group Pl with two formula units in a unit-cell of dimensions a = 12.506(6), b = 10.471(5), c = 18.396(13) Å, α = 93.07(4)°, β = 105.75(5)°, γ = 92.58(4)°. The structure was solved by direct and Fourier methods and refined by least-squares techniques to R = 0.061 for 3723 independent observed reflections. The structure consists of tetrabromocadmate (II) anions and triphenylbenzylphosphonium cations, both with a quasi-perfect tetrahedral symmetry around the cadmium and phosphorus atoms. The most significant average bond distances are: Cd-Br, 2.588(2) Å, P[sbnd]C (Phen), 1.794(5) Å and P[sbnd]CH2, 1.806(6) Å. The P[sbnd]C (Phen) bonds are in slightly distorted staggered conformation (gauche-, gauche +, and trans) in respect of the C (Phen)-CH2 bonds of the benzyl residues. The interatomic distances between the ions correspond to the usual Van der Waals distances. 相似文献
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《Journal of Coordination Chemistry》2012,65(4):215-220
Abstract The crystal and molecular structure of [Cu(p-NO2C6 H5CH2CONHCH2CO2)2 (H2O)2] has been determined by single-crystal, x-ray diffraction techniques. The compound is centrosymmetric crystallizing in a monoclinic unit cell (P21/c) with two molecules per unit cell. The cell dimensions are: a = 11.588(1)A, b = 11.405(1)A, c = 8.041(1)Å and β = 93.47 · (1). The structure was solved by Patterson methods and refined to a value of R = 0.063. The coordination about the copper assumes an unexpected square planar geometry in which two phenaceturic moieties are each coordinated through the carboxylic oxygen (Cu—O = 1.933A) and the two waters complete the coordination (Cu—Ow = 1.959Å). The overall conformation of the phenaceturic acid is retained although there is a rotation of 180° about the peptide C—N bond. 相似文献
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<正> The crystal structure of the title compound has been determined. PdC52H44N2P4, Mr = 927. 2, monoclinic, space group P21 /n, a =12. 102(2), b = 9.997(2), c=20. 254(5)(?),β=93. 80(2)°, V = 2445. 0(?)3, Z = 2, R =0. 075 and Rw = 0. 095 for 3535 observed reflections (I>3σ(I)), The palladium atom is located on the symmetric center and adopts a square planar coordination surroundings with two biphosphine ligands and two cyanide groups. The molecular structure in crystals is different from that in solution in which the molecule is very fluxional, probably due to the rapid alteration in coordination sites between the coordinated and uncoordinated phosphorus atoms of the biphosphine ligands. Their properties are also reported. 相似文献
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《Journal of Coordination Chemistry》2012,65(4):237-243
Abstract A three dimensional X-ray structural analysis of rubidium bis (pyridine-2,6-dicarboxylato)chromate(III), Rb[Cr(dipic)2], has been carried out. The structure was refined by full matrix least-squares methods, using 713 observed independent reflections recorded at room temperature, to a conventional weighted R of 0.034. The crystals are tetragonal with a=b=6.950(3) Å, c=29.47(1) Å, space group 14 1/a and Z=4. The point group symmetry of the [Cr(dipic)2]? ion is S4. The Cr–N and Cr–O distances (1.974(4) and 2.000(3) Å respectively) noticeably differ from the usual values in aminoacid chromium(III) complexes. The π bonding effect of the pyridine nitrogen atom corroborates the previous spectral studies on the sodium salt of this complex. The lability of [Cr(dipic)2]? in acid solution has been tentatively explained on the basis of the relatively severe strain within the complex ion. 相似文献
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《结构化学》1984,(1)
<正> Preliminary information. The vanadyl complexes are found to be increasingly used in the areas of catalysis, new materials research as well as in bio chemistry. Therefore, more attentions have been paid to such compounds. The title complex K_2[VO(C_2H_3O-3)_2(C_2H_2O_3)] H_2O has been prepared by reaction of VOSO_4 with hydroxyacetic acid in aqueous solution, with KOH added to a suitable PH value. 相似文献
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《结构化学》1985,(3)
<正> INTRODUCTION. The reaction oF MoCl_3·3H_2O with dithiocarbamate in organic solvents is a interesting research area. Thus, several dinuclear and trinuclear molybdenum complexes have been synthesized The dinuclear oxo-dridged molybdenum compound was obtained by this reaction in acetonmethanol mixed solvent. The molecular configuration has been characterized 相似文献
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<正> The compound [Et_4N]_2[Fe_2S_2(NO)_4] (M_r=556.36) crystallizes in the monoclinic,space group P 2_1/n with a=9. 688(3), b=10. 882(2), c=12. 625(2), β=97. 86(3)°, Z=2, V=1318. 4, D_c=1. 40g/cm~3, ;μ(MoK_a)=12. 8cm~(-1) and F(000)=588. The final R=0. 028 and R_w=0. 029 for 2041 reflections (I≥3σ(I)).The crystals of [Et_4N]_2[Fe_2S_2(NO)_4] consist of discrete cations [Et_4N]~+ and anions 相似文献
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《结构化学》1989,(1)
<正> C14H10N2,Mr =206.24, space group P21/n, a =5.861(3), b =10.230 (5), c =17.440(11) A,β=92.07(5)°,V= 1045(1) A3,Z=4, Dx=1.31 g.cm-3, MoKa radiation,u=0.73 cm-1,F(000)=432,R=0.063 for 1054 observed reflections. 2-Phenylquinoxaline molecule is approximately planar. The dihedral angle between the quinoxaline ring and the substituted phenyl ring is 7.0°. The C-C bond distance connecting these two rings is 1.495(4) A. The whole molecule is a conjugation system. 相似文献
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《结构化学》1985,(2)
<正> INTRODUCTION. In our attempts of chemical simulation of the active center of nitrogenase we have been interested in the reaction system of various ferrous thiolates with thiomolybdatee. In previous papers, we have reported the syntheses of ferrous monodentothiolates and their reactions with tetrathiomolybdate. The possible structure type of ferrous thiolates when bidentothiols are used inspired our interest in this work. 相似文献
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《结构化学》1993,(1)
<正> [Cu(C8H4F3O2S)2(C3H7NO)], Mr = 579. 0, monoclinic, P21/c, a = 9. 4851(6), b = 26. 6574(6), c=9.2619(6) A ,β=96.08(3)°, V = 2328.7A3, Z=4, Dc=1. 65gcm-3, μ(MoKa) = 7. 2cm-1, F (000) = 1172, MoKa radiation, final R = 0. 074 and Rw = 0. 068 for 1841 reflections with I≥3σ(Ⅰ). The Cu(Ⅱ) atom is coordinated by five oxygen atoms, one of which from DMF is in the axial position, to form a square pyramidal geometry. That the thenoyl groups in the ligands take the cis-form around the Cu(Ⅱ) atom is explained by the hydrogen bonding effect. 相似文献
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《结构化学》1989,(1)
<正> The crystal structure of (Cyanoethyloxy-ferrocenyl)-p-fluoro-phenyl methane (Fc-C(H)OCH2CH2CN, Mr=363.23) belongs to the monoclinic spacegroup P21/c with unit cell parameters: a =9.751(3), b =18.448(4), c =9.891(4)A,β= 105.71(3)°,V= 1712.7A3,Z=4,Dc=1.409g/cm3,μ=8.930cm-1,λ=0.71073A (MoKα),R=0.05. The structure and reactivities of the title compound are compared with those of its isomer. 相似文献
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《结构化学》1988,(3)
<正> The crystal and Molecular structure of [K(18-crown-6)](Bi(SCN)Cl3] has been deterained by X-ray diffraction Method. Its crystal is triclinic, space group Pl,with a = 9.233(4), b = 11.661(5), c=11.738(5)A,a= 81.82(4)° ,β=71.47(4)°,γ=75.55(4)°, and Z = 2. The final structural refine-ment converged with unweighted and weighted R factors of 0.051 and 0.047 for 2924 observed reflections. Results of the structure analysis indicate that the K+ ion enters the cavity of the 18-crown-6 to form the complex cation and one Bi(Ⅲ) atom, one SCN ligand and three Cl atoms fora the anion. Each Bi(Ⅲ) atoa is coordinated by four Cl atoas, of which two are shared with other Bi(Ⅲ) atom, one N atom and one S atoa from two SCN ligands respectively shared with a third Bi(Ⅲ) atoa, forming octahedral geometry. 相似文献
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《结构化学》1986,(3)
<正> The title compound, C24H20As2(Mr=458.24), crystallizes in mono-clinic with space group P21/n and a=6.268(2), b=7.494(2), c=21.340(7)A, β= 91.027(3)°, V=1002.6 A3, Z=2, D.x=1.518gcm-3. The final value of R is 0.059 for 1619 observed reflections. The four phenyls arrange in a staggered trans-conformation around the As-As' bond. 相似文献
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<正> C18H25NO5, Mr = 335.40, tetragonal, P41212, a = 15.578(4), c =14.723(3) A, V =3573(2) A3, Z = 8, D = 1.247 g cm-3, MoKα,λ= 0.71069 A, μ = 0.;85 cm-1, T = 293K, final R .= 0.100 and RW (on F2) = 0.080 for 1095 observed data [|FO| > 2σ(|FO|)]. The structure confirms the spectrbscopic assignment of a pentacyclic skeleton containing two α-methyl-γ-lactone rings, one ether and one tertiary amine. 相似文献