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1.
Fluorination of triphenylarsine oxide by aqueous hydrogen fluoride (1–40%) in the absence of glass readily gives triphenylarsine difluoride. When the reaction with dilute (1%) aqueous hydrogen fluoride is carried out in borosilicate glass apparatus, the glass participates in the reaction resulting in the formation of the crystalline 2:1 adduct 2Ph3AsO·HBF4. Crystals of this compound are monoclinic, P21/c, a = 12.926(4), b = 17.819(6), c = 14.994(4) Å, β = 98.97(3)°, Z = 4. The structure contains cations [(Ph3AsO)2H]+ in which O?O is 2.44(2)Å, and anions BF4?.  相似文献   

2.
The extraction of In(III) from 1M (Na,H)(Cl,ClO4) media with 4-acylpyrazol-5-ones (HL) in toluene at 25°C is described by equilibria In 3+ + 3 HL ? InL3 + 3 H+ (log K = 1.48, 1.03, 0.87 with acyl = benzoyl, lauroyl, 2-thenoyl), InCl 2+ + 2 HL ? InClL2 + 2 H+ (log K = 0.26, ?0.45, ?0.35 respectively) and In3+ + m Cl? ? InClm(3-m)+ (log βm available from literature). The extraction from 1M (Na,H)(Cl,NO3) medium is enhanced by addition of aliquat (TOMA+,Cl?) and the following synergic equilibrium takes place : InCl2 + (TOMA+,Cl?) ? (TOMA+, InCl2L2? (log K = 5.49, 5.25, 5.21 respectively). Cl? of (TOMA+,Cl?) is exchanged by NO3? with the equilibrium constant log K = 1.50. If (TOMA+,Cl?) is replaced by tri-n-octylammonium chloride, the synergic effect is largely reduced (log K = 4.17 with acyl = benzoyl). The extraction from chloride solutions containing ClO4? remains unchanged by addition of ammonium salts.  相似文献   

3.
The complexes [Zn(en)3]X2·n H2O, where en = ethylenediamine, X = Cl?, Br? or 12SO2?4, n = 1 or 0.5, and [Zn(tn)2]X2·n H2O, where tn=1,3-diaminopropane, X=Cl?, Br? or 12SO2?4, n = 0 or 0.25, have been synthesized and their thermal investigations carried out. The complexes were characterized by elemental analysis and IR spectral data. These complexes have been observed to decompose through several isolable as well as non-isolable complex species as intermediates during heating. [Zn(tn)2]SO4 undergoes solid-state phase transition in the temperature range 126–145°C. ZnenSO4 and ZntnX2 (X = Cl?, Br? or 12SO2?4) have been synthesized pyrolytically in the solid state from their corresponding mother diamine complexes. ZnenSO4 and ZntnX2 (X = Cl?, Br? or 12SO2?4) complexes decompose through non-isolable hemidiamine species. ZnX2 (X = Cl? or Br?) complexes of tn undergo melting after formation of the monodiamine species. In contrast, the corresponding en complexes undergo melting at non-stoichiometric composition. Diamine (en or tn) is found to be bridging in all monodiamine (en or tn) complexes; whilst their mother complexes possess chelated en or tn. The thermal stability sequence of en and tn complexes of Zn(II) is ZnCl2 < ZnBr2 < ZnSO4. ΔH values are reported for some steps of decomposition. Possible mechanistic paths have been reported for each step of decomposition.  相似文献   

4.
The extraction of Co(II) with mixtures of 1-phenyl-3-methyl-4-benzoyl-pyrazol-5-one ((H)PMBP) and tri-n-octylamine (TOA) is investigated in order to explore the influence of diluents and inorganic anions with synergistic acidic extractant + liquid anion exchanger systems. Although it is proved that the same species [HTOA]+ [Co(PMBP)3]? is extracted from various inorganic media, with toluene as the diluent, the presence of ClO4? SO42? or Cl? anion modifies the distribution of the anions which are associated to (HTOA)+ in the organic phase, leading to different synergistic equilibria; with Cl? or SO42?: CO(PMBP)2 + (HTOA+,PMBP?) ?(HTOA+,Co(PMBP)3? (log K = 6.10) and with ClO4? : Co(PMBP)2 + HPMBP + (HTOA+,ClO4? ? (HTOA+,Co(PMBP)3? + H+ + ClO4? (log K = 2.34) The same synergistic equilibrium is observed for the extraction of Ni(II) from ClO4? medium, with a comparable value of the constant (log K = 2.45). The synergistic effect is cancelled in n-octanol.  相似文献   

5.
Two compounds of the formulae (dppeH2)3[MOCl6]2 ·12H2O I and (dppeH2)3[Mo2Cl9]2II are described. For compound I, which proved to be active in olefin epoxidation, the crystal structure was determined. The rose-pink crystals are triclinic, space group P1 with a = 13.715(9), b3 = 14.686(7), c = 12.512(7) Å, α = 109.56(4), β = 97,98(4) and γ = 91.27(5)°, V = 2345 Å, Dm = 1.42 and Dc = 1.44 gcm?3, Z = 1. Block-diagonal least squares refinement of the structure has led to a final value of the conventional R factor of 0.049 for the 3914 independent reflections with I > 3σ(I). Bond distances are in the range: MoCl 2.439(2)–2.469(2) Å, and PC 1.771(9)–1.806(8) Å.  相似文献   

6.
The reaction between PCl3 and ReCl5 yielded at 200 °C the ionic tetrachlorophosphonium dirhenium nonachloride, (PCl4)[Re2Cl9]. Single crystal X-ray diffraction analysis revealed a monoclinic unit cell: a = 8.616(3) Å, b = 10.449(4) Å, c = 9.397(3) Å, β = 99.72(3)°, V = 833.9(5) Å3, Z = 2, sp. gr. P21/m, wR2 = 0.1083 and R1 = 0.0527. The ionic compound is built from tetrahedra PCl4+ and face-sharing bioctahedra Re2Cl9. The Re–Re distance, 2.724 Å, indicates the presence of direct Re-Re interaction.  相似文献   

7.
The crystal structure of Na[N{Si(CH3)3}2] has been determined from single-crystal x-ray diffraction data collected by counter methods. N-sodiohexamethyldisilazane crystallizes in the mono-clinic space group p21/n with unit cell parameters a = 9.426(3), b = 6.921(3), c = 17.974(5)Å, β = 93.83(2)°, and ?calc = 1.04 g cm?3 for z = 4 formula units. Least-squares refinement gave a final conventional R value of 0.034 for 1244 independent observed reflections. In the solid state the compound exists in a polymeric arrangement with an average Na-N distance of 2.355(4)Å. The methyl group are configured such that the angle of rotation of the trimethylsilyl moiety about the Si-N bond is 30° from the eclipsed position. The Si-N bond length is 1.690(5)Å, and the Si-N-Si bond angle is 125.6(1)°.  相似文献   

8.
An ampule reaction between Mo and PCl5 at 200 °C yielded (PCl4)2[Mo2Cl10], the first ternary compound in Mo–P–Cl system. Single crystal X-ray diffraction gave a triclinic unit cell: a = 6.870(1), b = 8.892(2), c = 9.423(2) Å, α = 100.24(2), β = 95.55(2), γ = 96.12(2)° (V = 559.3(2) Å3, Z = 1, sp. gr. P1, wR2 = 0.0575 and R1 = 0.0279. The ionic compound is built from edge sharing bioctahedra [Mo2Cl10]2– and two tetrahedra PCl4+. The averaged Mo–Clb distance, 2.503(1) Å, is longer than the Mo–Clt distance, 2.33(2) Å. The Mo … Mo distance, 3.77 Å, indicates the absence of a direct Mo–Mo interaction. Semiempirical and ab initio calculations showed the possibility for [Mo2Cl10]2– to exist with long and short Mo to Mo distances, the letter corresponding to the Mo–Mo bond.  相似文献   

9.
The crystal structure of a bis(triphenylphosphine)iminium salt of the 1:1 adduct of [FeH(CO)4]? and dimethyl acetylenecarboxylate has been determined from three-dimensional X-ray data collected by the counter method. Single crystals belong to the triclinic space space group P1, with two units of [C36H30NP2]+[C10H7FeO8]? in a cell of dimensions: a = 13.918(2), b = 15.669(5), c = 9.909(2) Å, α = 91.22(3), β = 94.83(2), and γ = 77.62(2)°. The structure was refined to a conventional R of 0.068 for 5373 observed
reflections. The resulting structure indicates that the complex anion is η3-[trans-2,3-bis(methoxycarbonyl)acryloyl]tricarbonylferrate, the coordination around the iron atom being described as a considerably distorted trigonal bipyramid. A comparison of the present structure with the structures of related complexes suggests that the η3-acryloyl portion is best represented as an intermediate of (η3-allyl) with the oxygen atom and (η2-olefin + η1-acyl). The short Fe-C(acyl) length of 1.897(5) Å implies an enhanced back-donation of electrons from the iron atom to the acyl group.  相似文献   

10.
The MIPO3Sm(PO3)3(MI = Li, Na, Ag) systems were studied. Differential thermal analysis and X-ray diffraction were used to investigate the liquidus and solidus relations. Three compounds LiSm(PO3)4, NaSm(PO3)4, and AgSm(PO3)4 were obtained which melt incongruently at 1248, 1143, and 1078 K, respectively. These compounds are isomorphous with their homologs LiLn(PO3)4, NaLn(PO3)4, AgLn(PO3)4 (Ln = Ce, La, Nd). They belong to the monoclinic system. The LiSm(PO3)4 unit cell parameters refined by least squares method are a = 16.43(3) Å, b = 7.16(1) Å, c = 9.65(3) Å, β = 125,9°(1), with the space group C2c and Z = 4. NaSm(PO3)4 and AgSm(PO3)4 are isotypic; they cristallize in the P21c space group, Z = 4; their unit cell parameters are, respectively, a = 12.18(1) Å, b = 13.05(1) Å, c = 7.25(5) Å, β = 126,53°(4), a = 12.25(1)A?, b = 13.06(1) Å, c = 7.201(9) Å, β = 126,57°(7). The ir spectra of the last two compounds indicate that these phosphates are chain phosphates.  相似文献   

11.
UO2(thd)2 CH3OH (thd = tetramethylheptane-3,5-dione) is monoclinic, with a = 10.602(11), b = 22.883(20), c = 12.054(11) Å and β = 105.90(3)°, Z = 4 and space group P21/c. The structure, which is molecular, was solved by conventional Patterson and Fourier techniques with 3173 independent (hkl) reflexions collected with MoKα radiation (λ = 0.7107 Å), and refined to R = σ(|Fo|-|Fc|)/σ|Fo| = 0.093. The uranium coordination polyhedron is a pentagonal bipyramid, with UO (carbonyl) distances between 2.25 and 2.37 Å and a longer UO (methanol) distance of 2.50 Å. The uranyl group is linear (uranyl angle 179.3(8)°). The pentagon oxygen atoms and uranium do not form a planar system, as there are deviations of up to 0.17 Å from the mean plane. If the methanol oxygen atom O(7) is excluded from the plane calculation, the remaining atoms are more nearly planar. The four carbonyl oxygens are coplanar, with uranium 0.08 Å from their plane. The methanol oxygen is 0.28(4) Å from this second plane.The two (thd) molecules, excluding methyl carbons, are planar and are inclined at 43.6° to each other in a boat form and at 29.1 and 14.5° to the pentagonal plane. The methanol CO bond is inclined at 133° to the UO bond, confirming the ligand is the neutral CH3OH molecule, and not CHO?3.  相似文献   

12.
The crystal structure of [HAlNCH(CH3)C6H5] 6·13 C6H14 has been determined by single crystal three-dimensional X-ray analysis. Block-matrix least-squares refinement led to conventional R factor of 0.08. The molecule is built up of a prismatic hexagonal framework, (AlN)6. Average AlN distances are 1.893(6) and 1.981(7) Å in the six-membered rings and in transverse bonds, respectively. Crystal data: hexagonal, space group P63, a 22.296(5), c 18.144(4) Å, V 7811.2 Å3, Z = 6, Dc 1.16 g cm?3.  相似文献   

13.
The thermal dissociation of the [Co(NH3)6]X3 (X = Cl?, Br?, I?, and NO?3), [Co(en)3]X3 (X = Cl?, Br?, I?, NO?3, HSO?4 and 12 C2O2?4), cis- [Co(en)2Cl2]Cl, and trans-[Co(en)2ClBr]NO3 complexes was investigated by an electrical conductivity (EC) technique. During the thermal dissociation reactions, liquid or semi-liquid phases are formed which cause large increases in the EC of the compound. The effect of concentration of the complex in a matrix medium as well as the composition of the matrix material on the EC curves were also determined.  相似文献   

14.
Ce6Mo10O39 crystallizes in the triclinic system with unit-cell dimensions (from single-crystal data) a = 10.148(5), Å, b = 18.764(6), Å, c = 9.566(5), Å, α = 103.12(7)°, β = 78.07(7)°, γ = 107.69(7)°, and space group P1, z = 2. The structure was solved using direct methods with 3113 countermeasured reflections (Mo radiation), and refined using Fourier and least-squares techniques to a conventional R of 0.039 (ωR = 0.047). Ce6Mo10O39 has a structure that consists of isolated MoO4 tetrahedra together with one corner-shared pair of tetrahedra, linked to irregular eight-coordinate Ce(III) polyhedra. The average MoO distance of 1.77 Å, and average CeO distance of 2.52 Å are in good agreement with previously reported values.  相似文献   

15.
Single crystal Na2TeO4 has been prepared by hydrothermal synthesis and its structure determined from three dimensional X-ray analysis. The crystal is monoclinic, space group PP21c with a = 10.632(5)Å, b = 5.161(2)Å; c = 13.837(11)Å, and β = 103.27(4)°. The crystal structure is built up of chains of Te(VI)O6 octahedra parallel to the [010] axis which can be formulated as [TeO4]n2n?. All sodium cations are in very distorted octahedral coordination.  相似文献   

16.
The structure of [Pt2Cl(CO) (μ-Ph2PCH2PPh2)2] [PF6] was determined by X-ray methods and refined to R = 0.082, using diffractometric intensities of 5646 independent reflections. The crystals are monoclinic, space group P21/n, a = 12.919(3), b = 15.576(6), c = 25.151(5)Å, β = 94.82(3)°, Z = 4. They are built of octahedral hexafluorophosphate anions and dinuclear platinum(I) cations. The latter contain PtCl and PtCO fragments linked to one another by a PtPt σ-bond and by two bridging bis(diphenylphosphino)methane ligands. The platinum atoms are in square planar environments and the dihedral angle between the two coordination planes is 40.1°. Selected bond lengths are: PtPt 2.620(1), PtCl 2.384(5), PtC 1.89(3) and PtP 2.291(5) – 2.308(5)Å.  相似文献   

17.
The crystal structure of tris(triphenylphosphine)gold(I)[dodecahydrido-6-thia-nido-decaborate(1—)], [(C6H5)3P]3AuB9H12S, has been determined using X-ray techniques and counter data. The compound is a salt consisting of [(C6H5)3P]3Au+ cations and B9H12S? anions. The cation is trigonal and nearly planar with AuP distances of 2.382(5) Å and PAuP anglés of 119.3(36)°. The B9H12S? thiaborane anion is an open icosahedral fragment with the S atom in the 6 position, on the periphery of the decaborane polyhedron. The structure is the same as that found in solution for the isoelectronic B10H142? anion. Crystals are triclinic, space group P1, with a = 13.086(12), b = 19.635(32), c = 11.180(8) Å, α = 103.60(16), β = 72.10(9), and γ = 94.76(15)°. The structure was refined by least squares to a conventional R of 0.077.  相似文献   

18.
EPR-Investigations of α-Dichloro-bis[chloro?bis(N,N?diethyldiselenocarbamato)molybdänum(V)] dichloride, [Mo2Cl4(däsc)4]Cl2. Preparation and bonding properties of the coordination sphere of [Mo2Cl4(däsc)4]Cl2 studied by EPR, are reported. The EPR-spectrum at 77°K can be described by an axial symmetric spin-HAMILTONian, the parameters of which are g| = 2.046, g|= 1.996, A| = 53.5 · 10?4 cm?1, and A| = 22.8 · 10?4 cm?1. No 77Se-ligand hyperfine structure could be observed. The very high g-values are explained as being caused by strong ligand spin-orbit interaction, CT-contributions and a high degree of co valency of tho Mo? Se bond. Using an MO-model of the symmetry C4v, the bonding parameters of the first coordination sphere have been calculated.  相似文献   

19.
The temperature dependent behaviour of PCl4AsCl6, PCl4SbCl6 and AsCl4SbCl6 has been investigated byRaman spectroscopy. The As(V) containing complexes decompose into homogeneous molecular melts consisting of AsCl3, Cl2 and PCl5, respectively. In PCl4SbCl6 PCl4 + and SbCl6 complex ions were found in the solid as well as in the molten state.
  相似文献   

20.
The synthesis of a second polymorph of ZrI2 has been achieved by a transport reaction between ZrI4 and zirconium metal under a 750850°C gradient in a sealed tantalum tube. The black lath-like crystals produced in the 775°C region occur in space group P21m with a = 6.821(2) Å, b = 3.741(1) Å, c = 14.937(3) Å, β = 95.66(3)°, Z = 4. A total of 669 independent reflections with 2θ ≤ 50° and I > 3σ(I) were measured at room temperature on a four-circle automated diffractometer with monochromatized Mo radiation and were corrected for absorption (μ = 190 cm?1). The structure was solved by direct methods and full-matrix least-squares refinement of all atoms with anisotropic thermal parameters to give final residuals R = 0.064 and Rw = 0.079. This phase is isoelectronic and isostructural with β-MoTe2, a distorted CdI2-type structure in which the zirconium atoms are displaced 0.440 Å from the octahedral centers along a to form infinite zigzag metal chains (dZrZr = 3.182(3) Å) parallel to b. The phase is a diamagnetic semiconductor at room temperature (Eg ~ 0.1 eV).  相似文献   

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