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1.
By replacing Mn in YCa3(MnO)3(BO3)4 with trivalent Al and Ga, two new borates with the compositions of YCa3(MO)3(BO3)4 (M=Al, Ga) were prepared by solid-state reaction. Structure refinements from X-ray powder diffraction data revealed that both of them are isostructural to gaudefroyite with a hexagonal space group P63/m. Cell parameters of a=10.38775(13)Å, c=5.69198(10)Å for the Al-containing compound and a=10.5167(3)Å, c=5.8146(2)Å for the Ga analog were obtained from the refinements. The structure is constituted of AlO6 or GaO6 octahedral chains interconnected by BO3 groups in the ab plane to form a Kagomé-type lattice, leaving trigonal and apatite-like tunnels. It is found that most rare-earth and Cr, Mn ions can be substituted into the Y3+ and M3+ sites, respectively, and the preference of rare-earth ions to locate in the trigonal tunnel is correlated to the sizes of the M3+ ions.  相似文献   

2.
A new ruthenium-rhodium mixed-metal cluster HRuRh3(CO)12 and its derivatives HRuRh3(CO)10(PPh3)2 and HRuCo3(CO)10(PPh3)2 have been synthesized and characterized. The following crystal and molecular structures are reported: HRuRh3(CO)12: monoclinic, space group P21/c, a 9.230(4), b 11.790(5), c 17.124(9) Å, β 91.29(4)°, Z = 4; HRuRh3(CO)10(PPh3)2·C6H14: triclinic, space group P1, a 11.777(2), b 14.079(2), c 17.010(2) Å, α 86.99(1), β 76.91(1), γ 72.49(1)°, Z = 2; HRuCo3(CO)10(PPh3)2·CH2Cl2: triclinic, space group P1, a 11.577(7), b 13.729(7), c 16.777(10) Å, α 81.39(4), β 77.84(5), γ 65.56°, Z = 2. The reaction between Rh(CO)4? and (Ru(CO)3Cl2)2 tetrahydrofuran followed by acid treatment yields HRuRh3(CO)12 in high yield. Its structural analysis was complicated by a 80–20% packing disorder. More detailed structural data were obtained from the fully ordered structure of HRuRh3(CO)10(PPh3)2, which is closely related to HRuCo3(CO)10(PPh3)2 and HFeCo3(CO)10(PPh3)2. The phosphines are axially coordinated.  相似文献   

3.
Two new compounds Pd2Os3(CO)12 , 13 and Pd3Os3(CO)12 , 14 have been obtained from the reaction of with Os3(CO)12 at room temperature. The products were formed by the addition of two and three groups to the Os–Os bonds of Os3(CO)12. Compounds 13 and 14 interconvert between themselves by intermolecular exchange of the groups in solution. Compounds 13 and 14 have been characterized by single crystal X-ray diffraction analyses.Dedicated to Professor Brian F. G. Johnson on the occasion of his retirement – 2005.  相似文献   

4.
The thermal decomposition reactions were determined for [Co(en)3](N03)3 and [Co(en)3(HSO4)3 in a dynamic nitrogen gas atmosphere and vacuo, where en represents ethylenediamine. Data were obtained using thermogravimetry, DTA, thermomagnetic analysis, and mass spectrometry. The dissociation reactions in nitrogen were found to be as follows:
and
In vacuo, the dissociation process for [Co(en)3](N03)3 is the same as in nitrogen. Also, the decomposition of [Co(en)3](HSO4)3 is the same except for the first step which is:
  相似文献   

5.
The magnetic properties of Cu(NH3)4(NO3)2 have been measured at low temperatures. Broad maxima in both the susceptibility and specific heat are observed and are consistent with linear chain behavior of a Heisenberg antiferromagnet, with J/k = 3.9 ± 0.1 K. Long-range order sets in at Tc = 0.15 ± 0.01 K, and the ratio kTc/|J| = 0.038 is the lowest observed as yet for a one-dimensional, S = 1/2 antiferromagnet.  相似文献   

6.
The nitrosation of Na[W(CO)5CN] using amyl nitrite and sulphuric acid in a two phase water— diethyl ether system gives the trinuclear compound W3(μCN)3(NO)3(CO)9. A single crystal X-ray diffraction study showed that the compound contains a nine-membered ring of three tungsten atoms and three bridging cyanide groups. The terminal carbonyl and nitrosyl ligands were not distinguishable.  相似文献   

7.
The thermolysis of complexes [Co(NH3)6][Fe(CN)6] and [Co(NH3 6]4[Fe(CN)6]3 under an air or hydrogen atmosphere at 200, 350, and 500°C is studied. The composition and properties of thermolysis products are determined. The oxidative thermolysis yields mixtures of oxides of the central metals; the reductive thermolysis yields intermetallic compounds CoFe. The density of the complexes and the specific surface area of the intermetallic compounds are measured. Average particle sizes are calculated. The morphology and dispersion of the powders are dictated by the shape and density of the crystals of the precursor double salts and the thermolysis temperature. The thermolysis chemism in the oxidative and reductive atmospheres is discussed in the context of the nature of the complex anion. Original Russian Text ? S.I. Pechenyuk, D.P. Domonov, D.L. Rogachev, A.T. Belyavskii, 2007, published in Zhurnal Neorganicheskoi Khimii, 2007, Vol. 52, No. 7, pp. 1110–1115.  相似文献   

8.
Electrical conductivities were measured for the ternary systems Y(NO3)3+La(NO3)3+H2O, La(NO3)3+Ce(NO3)3+H2O, La(NO3)3+Nd(NO3)3+H2O, and their binary subsystems Y(NO3)3+H2O, La(NO3)3+H2O, Ce(NO3)3+H2O, and Nd(NO3)3+H2O at (293.15, 298.15 and 308.15) K. The measured conductivities were used to test the generalized Young’s rule and the semi-ideal solution theory. The comparison results show that the generalized Young’s rule and the semi-ideal solution theory can yield good predictions for the conductivities of the ternary electrolyte solutions, implying that the conductivities of aqueous solutions of (1:3 + 1:3) electrolyte mixtures can be well predicted from those of their constituent binary solutions by the simple equations.  相似文献   

9.
X-ray crystallographic analyses of H2Os3(CO)10, H(SC2H5)Os3(CO)10 and (OCH3)2Os3(CO)10 are reported. Although hydrogen atom positions have not been located, the essential isostructural nature of the three commplexes establishes the hydride ligands as bridging two metal atoms, separated by 2.670 Å, with a formal bond order of two; the bridging hydrido- and thiolato-ligands span an osmium---osmium bond of length 2.863 Å and formal bond order one; the two μ-methoxy ligands bridge two metal atoms separated by 3.078 Å which, by simple 18 electron rule counting, has a metal---metal bond order of zero. Some general comments are made on the structures of polynuclear transition metal carbonyls.  相似文献   

10.
Phase equilibria in the Ba3(VO4)2-K2Ba(MoO4)2 and Pb3(VO4)2-K2Pb(MoO4)2 systems have been investigated. In the first system, a continuous series of substitutional solid solutions with the palmierite structure is formed, and in the second one, the polymorphic transition in lead orthovanadate at 100°C restricts the extent of the palmierite-type solid solution to 10–100 mol % K2Pb(MoO4)2. Original Russian Text ? V.D. Zhuravlev, Yu.A. Velikodnyi, A.S. Vinogradova-Zhabrova, A.P. Tyutyunnik, V.G. Zubkov, 2008, published in Zhurnal Neorganicheskoi Khimii, 2008, Vol. 53, No. 10, pp. 1746–1748.  相似文献   

11.
This contribution presents the results of a single crystal X-ray diffraction study of three ammine complexes of bivalent platinum and palladium: [Pt(NH3)4](N03)2, [Pd(NH3)4](N03)2 and [Pd(NH3)4]F2H2O. The first two compounds are isostructural; metal atoms are located on inversion centers, all other atoms are in general positions. A three-dimensional framework is built from planar-square complex cations and nitrate ions joined by N-H...O hydrogen bonds. In [Pd(NH3)4]F2H2O, palladium atoms, as in the previous cases, are located on inversion centers, while oxygen atoms of water molecules are on the two-fold symmetry axis. A network of strong N-H...F and O-H...F hydrogen bonds linking the cations, anions, and crystallization water molecules is present in the structure.  相似文献   

12.
Two single crystals[Ln(TBPO)4(NO3)2]NTf2 (Ln=Eu, Gd) were prepared and characterized by element analysis, single crystal X-ray diffraction, PXRD, FT-IR, TGA and fluorescence spectroscopy. The two compounds have similar coordinate structures, in which the central metal ion is coordinated by four TBPO (Tri-n-butylphosphine oxide) molecules and two bidentate nitrates, while NTf2-(bis(trifluor-(bis(trifluoromethylsulfonyl) imide anion) acts as the counter anion. The packing modes of the two crystals are same. The two single crystals are the focus on 8-coordinate tetra-TRPO complexes (TRPO is Trialkyphosphine oxides).  相似文献   

13.
Reactions of CpMoIr3(μ-CO)3(CO)8 (1) with stoichiometric amounts of phosphines afford the substitution products CpMoIr3(μ-CO)3(CO)8−x (L)x (L = PPh3, x = 1 (2), 2 (3); L = PMe3, x = 1 (4), 2 (5), 3 (6)) in fair to good yields (23–54%); the yields of both 3 and 6 are increased on reacting 1 with excess phosphine. Products 2–5 are fluxional in solution, with the interconverting isomers resolvable at low temperatures. A structural study of one isomer of 2 reveals that the three edges of an MoIr2 face of the tetrahedral core are spanned by bridging carbonyls, and that the iridium-bound triphenyiphosphine ligates radially and the molybdenum-bound cyclopentadienyl coordinates axially with respect to this Molr2 face. Information from this crystal structure, 31P NMR data (both solution and solid-state), and results with analogous tungsten—triiridium and tetrairidium clusters have been employed to suggest coordination geometries for the isomeric derivatives.  相似文献   

14.
Raman and FTIR spectra of guanidinium zinc sulphate [C(NH2)3]2Zn(SO4)2 are recorded and the spectral bands assignment is carried out in terms of the fundamental modes of vibration of the guanidinium cations and sulphate anions. The analysis of the spectrum reveals distorted SO42− tetrahedra with distinct S–O bonds. The distortion of the sulphate tetrahedra is attributed to Zn–O–S–O–Zn bridging in the structure as well as hydrogen bonding. The CN3 group is planar which is expressed in the twofold symmetry along the C–N (1) vector. Spectral studies also reveal the presence of hydrogen bonds in the sample. The vibrational frequencies of [C(NH2)3]2 and HC(NH2)3 are computed using Gaussian 03 with HF/6-31G* as basis set.  相似文献   

15.
Thermal degradation of the cluster compound Os3(CO)8(PPh2H)(μ3-S)2 (I) at 125°C leads to decarbonylation and formation of the new ligand bridged hexanuclear cluster Os6(CO)14(μ-PPh2)23-S)34-S) (II) in 11% yield. Space Group: P1, No. 2, a 10.427(5), b 13.552(3), c 17.919(3) Å, α 84.87(2), β 75.41(3), γ 78.43(3)°, V 2399(2) Å3Z = 2, ?calc 2.82 g cm?3. The structure was solved by the heavy atom method and refined (3223 reflections) to the final residuals R = 0.042 and Rw = 0.036. The molecule consists of two sulfido bridged open triosmium clusters which are linked by a bridging sulfido ligand and a bridging diphenylphosphino ligand.  相似文献   

16.
Results of Mössbauer measurements on Eu(NH3)6 provide strong evidence that the material contains divalent europium ions in the 4f7 configuration and orders magnetically at low temperatures.  相似文献   

17.
The complexes [Rh(η3-C3H4R)(η5-C5R′5)L]+BF4- (R  1-Me, R′  H, Me; R  2-Me, R′  H) (L  C5H5N, Ph3P, Ph3As) have been prepared from Rh(η3-C3H4R)(η5-C5R′5)Cl and AGBF4 in acetone, followed by reaction with the stoicheiometric quantity of L. The 1H and 13C NMR spectra of the salts are reported and discussed.  相似文献   

18.
Syntheses were developed, and compounds of composition (NH4)2x K2y Rb2z Th(NO3)6(x + y + z = 1) were prepared. These compounds were structurally studied using X-ray diffraction and IR spectroscopy. Incomplete miscibility in the solid phase of the title system was found, and the impossibility of existence of a hexanitratothorate complex in the (NH4)2Th(NO3)6-K2Th(NO3)6 system at 298.15 K and the component molar ratio 1: 3 was demonstrated. Calorimetric standard enthalpies of formation and mixing at 298.15 K were determined. Original Russian Text ? N.G. Chernorukov, A.V. Knyazev, A.A. Sazonov, 2009, published in Zhurnal Neorganicheskoi Khimii, 2009, Vol. 54, No. 7, pp. 1066–1071.  相似文献   

19.
The title compound can be prepared in good yield by heating either [Ru4(μ-H)4(CO)12] or [Au2Ru43-H)2(CO)12(PPh3)2] with [AuMe(PPh3)] in toluene. The related compound [Au3Ru43-H)(μ-dppm)(CO)12(PPh3)] has also been prepared. Both trigoldtetraruthenium clusters undergo dynamic behaviour in solution, involving intramolecular rearrangement of the metal core, as revealed by variable temperature NMR studies. The crystal structure of [Au3Ru43-H)(CO)12(PPh3)3] has been established by an X-ray diffraction study. The metal atom core comprises a trigonal bipyramidal AuRu4 unit with two AuRu2 faces capped by gold atoms.  相似文献   

20.
Double complex salts (DCSs) [Co(NH3)6][Fe(CN)6] (I) and [Co(NH3)6]2[Cu(C2O4)2]3 (II) and complex [Co(NH3)6]2(C2O4)3·4H2O (III) are synthesized and investigated by single crystal XRD, crystal optics, and elemental analysis. The crystalline phases of I, II, and III (R-3, P21/c, and Pnnm space groups respectively) have the following crystallographic characteristics: a = 10.9804(2) ?, b = 10.9804(2) ?, c = 10.8224(3) ?, V = 1130.03(4) ?3, Z = 3, d x = 1.65 g/cm3 (I); a = 9.6370(2) ?, b = 10.2452(2) ?, c = 13.2108(3) ?, V = 1932.90(9) ?3, Z = 2, d x= 1.97 g/cm3 (II), and a = 11.7658(3) ?, b = 11.7254(3) ?, c = 14.1913(4) ?, V = 1304.34(5) ?3, Z = 2, d x = 1.68 g/cm3 (III). This paper investigates the products of DCS thermolysis in a hydrogen atmosphere: the intermetallic compound CoFe with the bcc parameter a = 2.852 ? for I and a heterogeneous mixture of Co and Cu in the decomposition of II. The coordinated CN and C2O42− groups then turn into NH3, hydrocarbons, and CO2. The dominant hydrocarbon is methane.  相似文献   

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