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1.
The title compounds were made by reacting bis(diphenylphosphino)methane (dppm) with reduced solutions of OsCl64? and Ru2OCl104?. The crystal and molecular structures of these compounds have been determined form three-dimensional X-ray study. The cis-isomers crystallize with one CHCl3 per molecule of the complex. All three compounds crystallize in the monoclinic space group P21/n with unit cell dimensions as follows: Cis-OsCl2(dppm)2·CHCl3: a = 13.415(4) Å, b = 22.859(4) Å, c = 16.693(3) Å, β = 105.77(3)°, V = 4926(3) Å3, Z = 4. cis-RuCl2(dppm)2·CHCl3: a = 13.442(3) Å, b = 22.833(7) Å, c = 16.750(4) Å, β = 105.53(2)°, V = 4953(3) Å3, Z = 4. trans-RuCl2(dppm)2: a = 11.368(7) Å, b = 10.656(6) Å, c = 18.832(12) Å; β = 103.90(6)°, V = 2213(7) Å3; Z = 2. The structures were refined to R = 0.044 (Rw = 0.055) for cis-OsCl2(dppm)2·CHCl3; R = 0.065 (Rw = 0.079) for cis-RuCl2(dppm)2·CHCl3 and R = 0.028 (Rw = 0.038) for trans-RuCl2(dppm)2. The complexes are six coordinate with stable four-membered chelate rings. The PMP angle in the chelate rings is ca. 71° in each case.  相似文献   

2.
《Inorganica chimica acta》1988,141(1):145-149
This contribution reports the synthesis and characterization of the organothorium alkylthiolate complex [(CH3)5C5]2Th(SCH2CH2CH3)2. This compound crystallizes in the monoclinic space group C2/c (#15) with four molecules in a cell of dimensions a=19.066(2), b=11.603(1), c=16.379(2) Å, and β=130.08(1)°. Least-squares refinement led to a value for the conventional R index (on Fo) of 0.040 for 132 variables and 2030 observations having Fo2⩾3σ(Fo2). The molecular structure consists of an unexceptional ‘bent sandwich’ [(CH3)5C5]2Th fragment coordinated to two n-propylthiolate ligands. The ThS bond distance is 2.718(3) Å; the SC(α) distance, 1.78(2) Å; the ThSC(α) angle, 108.3(5)°; and the SThS′ angle, 102.5(2)°. Contrasts are drawn with the structures of analogous actinide alkoxides  相似文献   

3.
Nickel(II) complexes with the compartmental Schiff bases derived from 2,6-diformyl-4-chlorophenol and 1,5-diamino-3-thiapentane (H2L1) or 3,3′-diamino-N-methyl-dipropylamine (H2L2) were synthesized, and the crystal structures of [Ni(L1)- (py)2] and [Ni(L2)(dmf)]·H20 were determined by X-ray crystallography.Ni(L1)(py)2 is monoclinic, space group C2/c, with a= 18.457(6), b = 11.116(7), c= 16.098(6) Å, and β = 115.79(5)°; Dc = 1.49 g cm−3 for Z = 4. The structure was refined to the final R of 6.9%. The molecule has C2 symmetry. The nickel atom is six-coordinated octahedral. Selected bond lengths are: NiO 2.04(1) Å, NiN (L1) 2.08(1) Å, NiN(py) 2.17(1) Å.[Ni(L2)(dmf)]·H2O is monoclinic, space group P21/n, with a = 17.329(6), b = 13.322(7), c = 12.476(7) Å and β = 95.43(5)°; Dc = 1.45 g cm−3 for Z = 4. The structure was refined to the final R of 5.1%. The nickel atom is bonded in the octahedral geometry to the bianionic pentadentate ligand L2 and to one molecule of dimethylformamide. Selected bond lengths are: NiO (charged) 2.063(3) Å (mean value), NiO (neutral) 2.120(3) Å, NiN (planar) 2.050(3) Å (mean value), NiN (tetrahedral) 2.177(3) Å.  相似文献   

4.
The crystal structures of two copper(II) complexes of 4-fluorophenoxyacetic acid (4-FPAH) have been determined by X-ray diffraction. [Cu(4-FPA)2(H2O)2]·2(4-FPAH)·2H2O (1) is triclinic, space group P1 with Z = 1 in a cell of dimensions a = 14.808(2), b = 9.832(2), c = 6.847(2) Å, α = 87.77(2), β = 98.41(2), γ = 112.33(2)° and was refined to a residual of 0.038 for 1697 ‘observed’ reflections. The coordination sphere in this complex is tetragonally distorted octahedral comprising two waters [CuO, 1.940(3) Å], two unidentate carboxylate oxygens [CuO, 1.942(2) Å] and two ether oxygens [CuO, 2.471(2) Å]. Two adducted [4-FPAH] acid molecules are linked to the un-coordinated oxygens of the acid ligands by hydrogen bonds [2.547(4) Å]. [Cu2(4-FPA)4(2-aminopyrimidine)2] (2) is triclinic, space group P1 with Z = 1 in a cell of dimensions a = 12.688(2), b = 11.422(2), c = 7.951(1) Å, α = 78.74(1), β = 107.51(1), γ = 75.78(1)°, and was refined to a residual of 0.042 for 2683 ‘observed’ reflections. (2) is a centrosymmetric tetracarboxylate bridged dimer with four similar CuO (equatorial) distances [1.967–1.987 Å; 1.977(3) Å mean] and the axial position occupied by the hetero nitrogen of the 2-aminopyrimidine ligand [CuN, 2.176(3) Å]. The Cu---Cu separation is 2.710(1) Å. Crystal data are also presented which confirm the isostructurality of complex (2) with [Cu2(phenoxyacetate)4(2-aminopyrimidine)2], the CoII, MgII and MnII4-fluorophenoxyacetate complexes with their phenoxyacetic and 4-chlorophenoxyacetic acid analogues, and of CdII4-fluorophenoxyacetate with CdII and ZnII phenoxyacetates.  相似文献   

5.
《Inorganica chimica acta》1988,144(2):193-199
Addition of 1,2-W2Cl2(NMe2)4(W≡W) to a toluene slurry of LiCH(SiMe3)2(2 equiv) results in the formation of 1,2-W2[CH(SiMe3)2]2(NMe2)4(W≡W) (I) in 79% isolated yield. Compound I has been characterized by 1H and 13C NMR, IR, elemental analysis and single-crystal X-ray diffraction. The molecule exists exclusively in the gauche conformation in solution and in the solid state with WW = 2.320(1) Å. Compound I is very sterically encumbered as evidenced by: (1) large WWC angles, 110°, at the disyl ligand; (2) skewing of the NC2 planes of the NMe2 ligands off the WW vector; (3) anomalously large barriers to WNM2 bond rotation in solution; (4) the inertness of I towards CO2 and alcohols. However, compound I reacts with acetic anhydride to form 1,2-W2[CH(SiMe3)2]2(O2CMe)4(W≡W) (II) in 31% isolated yield. Compound II has been characterized by 1H and 13C NMR, IR, and elemental analysis. The mechanistic implications of these studies with regard to alcoholysis and CO2 insertion reactions of other 1,2-W2R2(NMe2)4 compounds are discussed. Crystal data for 1,2-W2[CH(SiMe3)2]2(NMe2)4 at −140°C: space group P21/n, a = 12.555(3), b = 18.699(5), c = 15.214(4) Å, β = 95.24(1)° and Z = 4.  相似文献   

6.
The extraction of U(VI)with dicyclohexano-18-crown-6 (mixed isomers or isomer A) from HCl medium is effective and selective, and can be used for separating and analysing uranium and thorium. However, little is known of the properties of the extraction complex of uranium with crown-ether in organic phase. In this paper we report the preparation, characteristic and structure of the crystalline extraction complex IaUO2Cl2HClH2O, Iabeing isomer A of dicyclohexano-18-crown-6.After extracting uranium(VI) from aqueous hydrochloric acid solution with Ia in 1,2-dichloroethane, the crystalline product of the extraction complex was prepared from the organic phase by diluting with a non-polar solvent at 25 °C. The content of uranium, crown-ether and HCl was determined. The IR spectrum of the crystals shows that the strong hydronium-crown ether/oxygen hydrogen bond absorption is found in the region 2300–2400 cm−1. The chemical shift in the range 9–12 ppm was observed. The 1H NMR signal of hydronium protons appears at 9.890 ppm. The results of assay correspond to the formula Ia2·(H3O+)2·UO2Cl42−.Crystal structure of the extraction complex has been determined by X-ray crystallography. Crystals are monoclinic, space group C2/c (No. 15) a=32.464, b=10.203, c=21.616 Å, β=119.73° and Z=4. In the complex each of the two H3O+ cations is anchored in the crown-ether cavity by three stronger hydrogen bonds (distances approximately 2.65 Å), whereas uranium forms UO2Cl42− with Cl as counterion about 8 Å away from the H3O+.  相似文献   

7.
Two compounds of empirical formula MCl3- (THF)3, M = V and Cr, have been characterized by single crystal X-ray studies. The VCl3(THF)3 molecule, which has a mer octahedral stereochemistry, crystallizes in the monoclinic space group P21/c with a= 8.847(2),b= 12.861(5),c= 15.134(3) Å, β = 91.94(2)°, V = 1721(1) Å3 and Z = 4. The V-Ci(1) and V-CI(2) distances have a mean value of 2.330 [3] Å while V-CI(3) = 2.297(2) Å, The VO(1) and VO(2) distances have a mean value of 2.061[8] Å while V-O(3) = 2.102(3) Å cis ClVCl angles average 92.0[5]° and cis OVO angles average 86.2[2]° . The isostmctural complex, CrCl3(THF)3, has a crystal structure made up of discrete octahedral mer-CrCl3(THF)3 molecules with the following unit cell dimensions (space group P21/c): a = 8.715(1), b= 12.786(3), c = 15.122(3) Å, β = 92.15(1)°, V = 1684(1) Å3 and Z = 4. The CrCl(1) and CrCl(2) distances have a mean value of 2.310131 Å while CrCl(3) = 2.283(2) Å. The CrO(1) and CrO(2) distances have a mean value of 2.0101171 Å while CrO(3) = 2.077(4) Å. cis ClCrCl angles average 90.9[4]° and cis OCrO angles average 86.1 [2]°. The structures of these two octahedral complexes and those previously reported for ScCl3(THF)3 and TiCl3(THF)3 are compared and certain general trends are discussed.  相似文献   

8.
《Inorganica chimica acta》1986,115(2):147-151
In the presence of Fe3+, template condensation of the fluorinated keto-alcohol CH3C(O)CH2C- (CF3)2OH with the triamine CH3C(CH2NH2)3 leads to two products: a fully condensed, imino-alkoxy, iron(III) complex, Fe{CH3C[CH2NC(CH3)CH2C(CF3)2O]3}, and a partially condensed iron(III) complex, O{FeCH3C[CH2NC(CH3)CH2C(CF3)2O]2(CH2NH2)}2, in which two six-coordinate iron(III) centers are linked by an oxide ion. A complete crystal and molecular structure determination of the latter has been made.Crystals are monoclinic, space group C2/c, a= 13.886(4); b=23.206(5); c=15.241(4) Å; β= 106.55(2)°; V=4708 Å3; Z=4. Least-squares refinement on F of 322 variables using 2627 observations converged at a conventional agreement factor of 3.8%. The Fe to bridging oxide distance is 1.811(1) Å, the FeFe distance 3.468 Å, and the FeOFe angle 146.6(2)°. A comparison is made between this structure and those of natural hemerythrin systems.  相似文献   

9.
《Inorganica chimica acta》1986,112(2):147-152
Nb2Cl6(THT)3, THT=tetrahydrothiophene, reacts with excess tetramethylammonium acetate to give an ionic Nb(III) complex, (NMe4)[Nb2Cl2(THT)(CH3CO2)5]·CH2Cl2. The compound has been characterized by NMR, IR, cyclic voltammetry and X-ray crystallography. It crystallizes in an orthorhombic space group P212121 with a=11.326(3) Å, b=11.857(4) Å, c=24.343(6) Å, V=3269(3) Å3 and Z=4. The NbNb distance is equal to 2.764(1) Å which together with the diamagnetism of the complex indicates a double metal-metal bond. The acetato ligands coordinate in three different modes: bridging bidentate, chelating and bridging unidentate.  相似文献   

10.
11.
The compound VOCl2·2(3-Etpy)·H2O (Etpy = ethylpyridine) was prepared by slow hydrolysis of the toluene suspension obtained from the reaction of VCl4 with 3-ethylpyridine The crystal was found to be monoclinic C2/c, Z = 4, ϱ(calc.) = 1.426 × 103 kg m−3, a = 13.281(5), b = 13.989(7), c = 9.277(8) Å, V = 1723(2) Å3 β = 90.53(5)°.Final full matrix least-square refinement with anisotropic thermal parameters for all non-hydrogen atoms gave R = 0.039, Rw = 0.042, Rg = 0.053. The vanadium atom is hexacoordinate with the pyridine ligands in mutually trans positions in the plane containing the Cl atoms. The O vanadyl atom is in an axial position trans to the coordinated H2O molecule, and the OVO line is a binary axis for the molecule.  相似文献   

12.
《Inorganica chimica acta》1988,146(1):123-127
The compounds of general formula [Ln(DMF)3- (H2O)6](CF3SO3)3 (Ln = LaEu, Tb, Dy) were synthesized and characterized by microanalysis, conductance measurements, IR absorption (Nd3+) and emission (Eu3+) spectra. The crystal structure of the neodymium compound was determined by X-ray diffraction techniques. The compound crystallizes in the triclinic system, space group P1, a = 8.589(4), b = 11.222(2), c = 12.271(2) Å, α = 56.83(2), β = 62.13(2), γ = 75.14(2)°, V = 875.2 Å3, M = 918.4, Z = 1, Dc = 1.73 g cm−3, λ(Mo Kα) = 0.71073 Å, μ = 1.65 mm−1, F(000) = 456, R = 0.056, Rw = 0.057, for 2979 independent reflections with I > 3σ(I). Nd3+ is coordinated to the oxygen atoms of six independent water molecules at a mean distance NdO = 2.52(1) Å, and to the oxygen atoms of three independent DMF groups at a mean distance NdO = 2.40(2) Å. The coordination polyhedron is a tricapped trigonal prism of point symmetry C3v.  相似文献   

13.
《Inorganica chimica acta》1987,128(2):161-167
The complexes (Bu4N)[TcO(O2C6H4)2] (1) and Na[TcO(OCH2CH2O)2] (2) have been prepared by reacting TcOCl4- with respective diols in methanol. Compound 2 was identified by its elemental analysis and field desorption mass spectrum. Crystals of compound 1 are monoclinic, C2/c, with cell dimensions a = 10.393(3), b = 13.835(3), c = 20.643(5) Å, β = 101.74(3)° and four formula units in the unit cell. The crystal structure was determined by standard methods and refined to R1 = 0.0694, R2 = 0.0613, on the basis of 2887 independent reflections. The data were collected with use of Mo Kα radiation and a Syntex P21 diffractometer. The anion of 1 is square pyramidal with a short TcO(oxo) bond (1.648(5) Å). TcO distances to the diolate groups are longer (1.956(3), 1.958(3) Å). The technetium atom lies 0.7014(4) Å out of the plane of the four diolate oxygen atoms. Compound 2 is hydrolytically unstable in pure water, but can be stabilized by the addition of a several-fold molar excess of ethylene glycol. Compound 1 decomposes minimally in pure water after 24 h. These complexes are shown to be good structural models for 99mTc-radiopharmaceuticals containing purely oxygen-donor ligands. Comparison of the physical properties of the structurally characterized members of the series of complexes with core structures TcOSxO(4-x) (x = O, 2, 4) shows a shift to low energy in the frequency of the terminal oxygen-technetium band in the IR correlated with increasing softness of the basal plane donor atom set.  相似文献   

14.
The crystal structure of the title compound, SnCl(C6H5)(C4H9)[S2CN(C2H5)2], was determined and refined to an R factor of 3.2% for 4876 reflections. The molecule contains five-coordinate tin in a distorted trigonal bipyramidal arrangement with the tin atom lying 0.20 Å below the equatorial plane formed by one of the sulphur atoms, S(1), and the donor carbons of the butyl and phenyl groups. The chlorine and the other sulphur atom, S(2), occupy axial sites, making a S(2)SnCl angle of 156.85(1)°. The SnS(2) bond is markedly elongated (2.764(1) Å) compared to the SnCl bond (2.449(1) Å) and the SnS(1) bond (2.454(1) Å). The structure resembles those of analogues such as (C6H5)2Sn(glygly) in having both hydrocarbon ligands located in the equatorial plane. Crystal data: space group P1: a = 8.291(2) Å, b = 14.726(3) Å, c = 9.509(2) Å, α = 96.24(2)°, β = 107.02(3)°, γ = 116.70(2)°, Z = 2, R = 3.2% for 4876 independent reflections.  相似文献   

15.
《Inorganica chimica acta》1986,114(2):111-117
Some uranyl(VI) complexes with new acyclic and cyclic Schiff base compartmental ligands have been prepared and characterized. The ligands have been obtained by reaction of 4-chloro-2,6-diformylphenol and polyamines of the type NH2(CH2)2X (CH2)2NH2 (X= NH, S). The structure of the uranyl(VI) complex with the ligand 1,7,15,21-tetra- aza-4,18-dithia-11,25-dichloro 8,22-bis-metadiphenyl cyclophane-gb-7,14,21,28 has been determined by X-ray crystallography. The compound crystallizes in the orthorhombic space group Pbca with eight formula units in a cell of dimensions a = 26.654(3), b = 22.871(3), c = 8.875(5) Å. The structure was solved by standard methods and refined by full- matrix least squares to the conventional R index of 4.6% for 2678 independent observed reflexions. Five donor atoms (including sulphur) of the ligand are equatorially bonded to the uranyl group to form discrete monomeric molecules with the seven-coordinated metal in the usual distorted pentagonal bipyramidal coordination geometry. Selected bond distances are: UO (equatorial), 2.22(1) and 2.25(1) Å; UN, 2.60(1) and 2.59(1) Å; US, 3.018(4) Å.  相似文献   

16.
The crystal structures of the organocobalt complexes, pyCo(GH)2Me(1), pyCo(GH)2Et(2) and pyCo(GH)2Pri(3) (py = pyridine, GH = monoanion of glyoxime) are reported. Compound (1) crystallizes in the space group P212121 with cell parameters a = 8.508(1), b = 13.586(2) and c = 11.614(6) Å; (2) crystallizes in the space group P212121 with cell parameters a = 8.448(4), b = 12.164(2) and c = 13.651(2) Å; (3) crystallizes in the space group P21/c with cell parameters a = 8.443(7), b = 12.913(2), c = 14.341(2) Å and β = 92.86(4).The three structures have been solved by Patterson and Fourier methods and refined by least squares methods to final R values of 0.045(1), 0.068(2) and 0.057(3) using 1819(1), 1653(2) and 1582(3) independent reflections. The pyCoalkyl fragment shows significant variation of CoN and CoC bond lengths. The latter increase from 2.003(4) to 2.084(9) Å following the increase of the alkyl bulk. The CoN(py) distances increase from 2.064(3) to 2.101(6) Å with the increasing σ-donor power of the alkyl group trans to pyridine. In comparison with cobaloximes having the same axial ligands, pyCo(DH)2alkyl (DH = monoanion of dimethylglyoxime) does not show significant differences on the pyCo alkyl fragment. CoN axial bond lengths and exchange rates of the axial neutral ligand are consistent for the two series, although changes in bond lengths are detected only when rate constants are from two to three orders of magnitude different.  相似文献   

17.
《Inorganica chimica acta》1988,149(2):177-185
CpRuCl(PPh3)2 reacted with excess R-DAB in refluxing toluene to give CpRuCl(R-DAB(4e)) (1a: R = i-Pr; 1b: R = t-Bu; 1c: R = neo-Pent; 1d: R =p-Tol). 1H NMR and 13C NMR spectroscopic data indicated that in these complexes the R-DAB ligand is bonded in a chelating 4e coordination mode.Reaction of 1a and 1b with one equivalent of [Co(CO)4] afforded CpRuCo(CO)3(R-DAB(6e)) (2a: R = i-Pr; 2b: R = t-Bu). The structure of 2b was determined by a single crystal X-ray structure determination. Crystals of 2b are monoclinic, space group P21/n, with four molecules in a unit cell of dimensions: a = 16.812(4), b = 12.233(3), c = 9.938(3) Å and β = 105.47(3)°. The structure was solved via the heavy atom method and refined to R = 0.060 and Rw = 0.065 for the 3706 observed reflections. The molecule contains a RuCo bond of 2.660(3) Å and a cyclopentadienyl group that is η5-coordinated to ruthenium [RuC(cyclopentadienyl) = 2.208(3) Å (mean)]. Two carbonyls are terminally coordinated to cobalt (CoC(1) = 1.746(7) and CoC(2) = 1.715(6) Å) while the third is slightly asymmetrically bridging the RuCo bond (RuC(3) = 2.025(6) and CoC(3) = 1.912(6) Å). The RuC(3)O(3) and CoC(3)O(3) angles are 138.4(5)° and 136.5(5)°, respectively. The t-Bu-DAB ligand is in the bridging 6e coordination mode: σ-N coordinated to Ru (RuN(2) = 2.125(4) Å), μ2-N′ bridging the RuCo bond and η2-CN coordinated to Co (RuN(1) = 2.113(5), CoN(1) = 1.941(4) and CoC(4) = 2.084(5) Å). The η2-CN′ bonded imine group has a bond length of 1.394(7) Å indicating substantial π-backbonding from Co into the anti-bonding orbital of this CN bond.1H NMR spectroscopy indicated that 2a and 2b are fluxional on the NMR time scale. The fluxionality of 6e bonded R-DAB ligands is rarely observed and may be explained by the reversible interchange of the σ-N and η2-CN′ coordinated imine parts of the R-DAB ligand.  相似文献   

18.
《Inorganica chimica acta》1988,143(2):185-192
Ta2Cl6(SMe2)3 reacts with PhHNNHPh to afford Ta2Cl4(μ-Cl)2(μ-PhN)(PhNH2)3 (1) a compound with a TaIVTaIV single bond, with a length of 2.644(1) Å. The compound crystallizes in space group Pnma with unit cell dimensions a = 22.960(8), b = 16.875(4), c = 6.367(3) Å, V = 2467(1) Å3, and Z = 4. The reaction of Nb2Cl6(SMe2)3 with PhHCNNCHPh, merely on mixing at room temperature produced Nb2Cl6(SMe2) [PhHC(N)PhHCNHNCHPh]·C7H8 (2) as large red crystals in ca. 50% yield. The molecule consists of two NbIV atoms, one six-coordinate and the other seven-coordinate, united by three bridging atoms (Cl, Cl, N) and a NbNb bond of length 2.681(1) Å. The way in which the tridentate triazo ligand is generated is completely obscure. Crystallographic data for 2: space group P21/n with a = 11.393(3), b = 11.988(3), c = 27.233(7) Å, β = 100.75(2)°, V = 3654(3) Å, and Z = 4.  相似文献   

19.
2-Deoxy-β-d-arabino-hexopyranose, C6H12O5, is orthorhombic, P212121, with cell dimensions at ?150° [20°], a = 6.484(2) [6.510(3)], b = 10.364(2) [10.427(4)], c = 11.134(3) [11.153(5)] Å, V = 748.2 [757.1] Å3, Z = 4, Dx = 1.457 [1.440], and Dm = [1.455] g.cm?3. The intensities of 1269 reflections were measured by using MoKα radiation. The structure was solved by direct methods, and refined by full-matrix least-squares, with anisotropic, thermal parameters for the carbon and oxygen atoms, and isotropic parameters for the hydrogen atoms. The pyranose has the 4C1(d) conformation, with puckering parameters Q = 0.563 Å, θ = 3.9°, and ? = 350.3°. The departure from ideality is very small, and less than that in β-d-glucopyranose, Q = 0.584 Å and θ = 6.9°. The β-glycosidic, CO bond is short, 1.383(4) Å, and the OCOH torsion angle is ?87°, consistent with the anomeric effect. The hydrogen-bonding scheme consists of infinite chains, with side chains terminating at a ring-oxygen atom.  相似文献   

20.
The complexes M(NCS)4·xL (x = 2, M = U, L = Me3CCON(Pri)2(dippva); x = 3, M = Th, L = Me2CHCON(Pri)2(dipiba) and dippva, M = U, L = EtCON(Pr1)2(dippa), dipiba and dippva; x = 4, M = Th, L = MeCON(Pri)2(dipa), dippa and dipiba, M = U, L = dipa, dippa) and the solvates M(NCS)4·4dipa·CH2Cl2 (M = Th, U) have been prepared. Their i.r. and u.v.-visible (M = U only) spectra are reported. The crystal and molecular structure of U(NCS)4(dipa)4· CH2Cl2 has been determined by the heavy-atom method from X-ray diffractometer data and refined by least squares to R 0.029 for 1135 independent reflections. The crystal is tetragonal, space group P421c, with Z = 2, a = 15.663(4) and c = 10.512(3) Å. The coordination geometry about the 8-coordinate uranium atom is dodecahedral with the N atoms of the NCS groups occupying the dodecahedral A sites and the ‘dipa’ O atoms the B sites. The bonding distances of UO and UN are 2.363(8), and 2.444(11) Å respectively.  相似文献   

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