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1.
2.
The rare earth-nickel-indides Tm2Ni1.896(4)In, Tm2.22(2)Ni1.81(1)In0.78(2), Tm4.83(3)Ni2In1.17(3), and Er5Ni2In were synthesized from the elements by arc-melting and subsequent annealing for the latter three compounds. Three indides were investigated by X-ray powder and single crystal diffraction: Mo2FeB2 type, P4/mbm, Z=2, a=731.08(4), c=358.80(3) pm, wR2=0.0201, 178 F2 values, 13 variables for Tm2Ni1.896(4)In, a=734.37(7), c=358.6(1) pm, wR2=0.0539, 262 F2 values, 14 variables for Tm2.22(2)Ni1.81(1)In0.78(2), and Mo5SiB2 type, I4/mcm, a=751.0(2), c=1317.1(3) pm, wR2=0.0751, 317 F2 values, 17 variables for Tm4.83(3)Ni2In1.17(3). X-ray powder data for Er5Ni2In revealed a=754.6(2) and c=1323.3(5) pm. The Mo2FeB2 type structures of Tm2Ni1.896(4)In and Tm2.22(2)Ni1.81(1)In0.78(2) are intergrowths of slightly distorted CsCl and AlB2 related slabs, however, with different crystal chemical features. The nickel sites within the AlB2 slabs are not fully occupied in both indides. Additionally In/Tm mixing is possible at the center of the CsCl slab, as is evident from the structure refinement of Tm2.22(2)Ni1.81(1)In0.78(2). The Mo5SiB2 type structures of Tm4.83(3)Ni2In1.17(3) and Er5Ni2In can be considered as an intergrowth of distorted CuAl2 and U3Si2 related slabs in an ABAB′ stacking sequence along the c-axis. Again, one thulium site shows Tm/In mixing. The U3Si2 related slab has great structural similarities with the Mo2FeB2 type structure of Tm2Ni1.896(4)In and Tm2.22(2)Ni1.81(1)In0.78(2). The crystal chemical peculiarities and chemical bonding in these intermetallics are briefly discussed.  相似文献   

3.
The geometric structures and conformational properties of trifluoromethanesulfonic anhydride, (CF3SO2)2O, and bis(trifluoromethylsulfonyl)difluoromethane, (CF3SO2)2CF2 have been studied by gas electron diffraction (GED) and ab initio calculations (HF/3–21G*). The calculations predict for both systems two stable conformers with C2 symmetry and one with C1 symmetry. In both compounds structures with C2 symmetry and dihedral angles SOSC ≈ 100° ((CF3SO2)2O) and SCSC≈ 150° ((CF3SO2)2CF2 are lowest in energy. According to the GED analyses the dominant conformer of (CF3SO2)2O2 possesses C2 symmetry with SOSC dihedral angles of 99.1(14)°. The presence of up to 30% of the two other conformers cannot be excluded; for (CF3SO2)2CF2 only one conformer with C2 symmetry and SCSC dihedral angles of 143(2)° is observed. A complete set of geometric parameters is given.  相似文献   

4.
The geometric structures and conformational properties of trifluoromethanesulfonic anhydride, (CF3SO2)2O, and bis(trifluoromethylsulfonyl)difluoromethane, (CF3SO2)2CF2 have been studied by gas electron diffraction (GED) and ab initio calculations (HF/3–21G*). The calculations predict for both systems two stable conformers with C2 symmetry and one with C1 symmetry. In both compounds structures with C2 symmetry and dihedral angles SOSC ≈ 100° ((CF3SO2)2O) and SCSC ≈ 150° ((CF3SO2)2CF2) are lowest in energy. According to the GED analyses the dominant conformer of (CF3SO2)2O possesses C2 symmetry with SOSC dihedral angles of 99.1(14)°. The presence of up to 30% of the two other conformers cannot be excluded; for (CF3SO2)2CF2 only one conformer with C2 symmetry and SCSC dihedral angles of 143(2)° is observed. A complete set of geometric parameters is given.  相似文献   

5.
Le sel double Cs2Mg(MoO4)2, 4H2O cristallise dans le syste`me monoclinique, groupe d'espace P21/c avecZ = 2. La structure ae´te´re´soluea`l'aide d'une synthe`se de Patterson et de sommations de Fourier tridimensionnelles. La valeur finale du facteur de reliabilite´estR = 0.068. L'environnement octae´drique du magne´sium est assure´par quarte mole´cules d'eau et deux atomes d'oxyge`ne de groupements molybdates. Dans le cas du sel (NH4)2Mg(MoO4)2, 2H2O qui cristallisee´galement dans le syste`me monoclinique, groupe d'espace P21/c avec Z = 2, l'environnement du magne´sium est assure´par deux mole´cules d'eau et quatre atomes d'oxyge`ne de groupements molybdates. La structure est de type “kro¨hnkite”. La valeur finale du facteur de reliabilite´est: R = 0.061.  相似文献   

6.
The P-functional organotin dichloride [Ph2P(CH2)3]2SnCl2 (3) is synthesized by reaction of Ph2P(CH2)3MgCl with SnCl4 independently of the molar ratio of the starting compounds. The corresponding organotin trichlorides Ph2P(CH2)nSnCl2R (4: n=2, R=Cl; 5: n=3, R=Cl; 6: n=3, R=Me) are formed in a cleavage reaction of Ph2P(CH2)nSnCy3 (n=2, 3) with SnCl4 or MeSnCl3, respectively. The main features of the crystal structures of 3–6 are both intra- and intermolecular PSn coordinations and the existence of intermolecular Sn---ClSn bridges. For further characterization of the title compounds, the adducts 4(Ph3PO)2 (7) and 5(Ph3PO) (8), as well as the P-oxides and P-sulfides of 3–6 (9–15), are synthesized. The results of crystal structure analyses of 7, 11, 12, and 14 are reported. The structures of 9–15 are characterized by intramolecular P=XSn interactions (X=O, S). A first insight into the structural behavior of the compounds 3–15 in solution is discussed on the basis of multinuclear NMR data.  相似文献   

7.
8.
The complex [Re2(HPO4)2(H2PO4)2(H2O)2] · 4H2O (I) was synthesized and investigated by conductometric, potentiometric, electronic and vibration spectroscopic methods. Thermal behavior of the title compound was studied and its molecular structure was determined from X-ray diffraction data. In the dimeric neutral complex, the bridging pairs of the hydrophosphate and dihydrophosphate groups close four five-membered Re-O-P-O-Re chelate rings. The O atom of water molecule occupies the axial position in the metal coordination polyhedron. The Re-Re distance 2.2168(8) ? corresponds to quadruple bond. Original Russian Text ? A.V. Shtemenko, V.G. Stolyarenko, K.V. Domasevich, 2007, published in Koordinatsionnaya Khimiya, 2007, Vol. 33, No. 2, pp. 83–88.  相似文献   

9.
The solubility polytherms in the systems for which the cryoscopic data are lacking were measured. The structural models of the electrolyte solutions were discussed on the basis of the solubility polytherms.__________Translated from Zhurnal Prikladnoi Khimii, Vol. 78, No. 3, 2005, pp. 413–417.Original Russian Text Copyright © 2005 by Pestova, Myund, Khripun, Prigaro.  相似文献   

10.
The reactions of lanthanide tris(borohydrides) Ln(BH4)3(thf)3 (Ln = Sm or Nd) with 2 equiv. of lithium N,N′-diisopropyl-N′-bis(trimethylsilyl)guanidinate in toluene produced the [(Me3Si)2NC(NPri)2]Ln(BH4)2Li(thf)2 complexes (Ln = Sm or Nd), which were isolated in 57 and 42% yields, respectively, by recrystallization from hexane. X-ray diffraction experiments and NMR and IR spectroscopic studies demonstrated that the reactions afford monomeric ate complexes, in which the lanthanide and lithium atoms are linked to each other by two bridging borohydride groups. The complexes exhibit catalytic activity in polymerization of methyl methacrylate. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 441–445, March, 2007.  相似文献   

11.
Three tin (Ⅳ) complexes with N,N-dialkyl dithiocarbamates Ph3SnS2CN(CH3)C6H5 (1),Ph3SnS2CN(C4H8NH) (2) and Sn(Cl)2(S2CNEt2)2 (3) have been synthesized. The crystal structures have been determined by X-ray sin- gle crystal diffraction. A crystal of the complex 1 is triclinic with space group P1, a=0.9485(3)nm, b=1.0491(3)nm, c=1.3631(4)nm, α=70.996(4)°, β=72.294(4)°, γ=79.609(4)°, Z=2, V=1.2168(6)nm3, Dc=1.453g·cm-3, μ=1.234mm-1, R=0.0442, wR=0.0858. A crystal of the complex 2 is monoclinic with space group P2(1)/c, a=1.2214(2)nm, b=1.1651(2)nm, c=1.5769(3)nm,β=99.039(2)°, Z=2, V=2.2162(7)nm3, Dc=1.532g·cm-3, μ=1.352mm-1, R=0.0267, wR=0.0591. A crystal of the complex 3 is triclinic with space group P1, a=0.7179(2)nm, b=0.9256(3)nm, c=1.5327(5)nm,α=93.857(4)°,β=98.992(4)°, γ=109.481(4)°, Z=2, V=0.9405(5)nm3, Dc=1.717g·cm-3, μ=2.076mm-1, R=0.0263, wR=0.0662. In the complexes 1 and 2 the tin atoms rendered five-coordination in a distorted tigonal bipyramidal structure and in the complex 3 the tin atom rendered six-coordination in a distorted octahedron structure. CCDC: 1, 179918; 2, 180024; 3, 180004.  相似文献   

12.
An aqueous solution of (hydroxymethyl)triphosphine [(HOCH2)2P(CH2)2]2PCH2OH (II) was synthesized in situ by treatment of the triphosphine H2P(CH2)2PH(CH2)2PH2 with formaldehyde. Addition of a CH2Cl2 solution of trans-PdCl2(PhCN)2 to an in situ aqueous solution of II resulted in the formation of a species thought to be [PdCl{[(HOCH2)2P(CH2)2]2PCH2OH}]+Cl. Attempts to isolate the complex were unsuccessful because of conversion to material containing small amounts of phosphine oxide(s) formed via a redox reaction involving water. The triphosphine trioxide [(HOCH2)2P(O)(CH2)2]2P(O)CH2OH was readily isolated from an in situ solution of II by treatment with aqueous H2O2.  相似文献   

13.
(C6H5)3MX2 (M = As, Sb; X = OCOCF3 and M = Sb, Bi; X = SO3F, SO3CF3) compounds prepared by the interaction of triphenylmetal(V) substrates with (CF3CO)2O, (CF3SO2)2O and (FSO2)2O have been characterized by molecular weight determination, elemental and spectroscopic (IR, 1H and 19F NMR, mass) analyses.  相似文献   

14.
Rate coefficients for collisional removal of O(1D) by six atmospheric gases have been measured by monitoring the appearance of O(3P) following photolytic production of O(1D). The measured values, kM±2σ, in units of 10?11 cm?3 molecule ?1 s?1 are kO3 = 22.8±2.3, kN2 = 2.52 ± 0.25, kCO2 = 10.4 ± 1.0,kH2O 195± 2.0, kN2O = 11.7 ± 1.2, and kH2, = 11.8±1.2.  相似文献   

15.
The compounds K4Ti(O2)4·2H2O, K3Ta(O2)2F4 and K2V2O3(O2)2F2 undergo photolysis in the solid state. The photolysis kinetics obey the parabolic rate equation p = kt1/2 and indicate a monoexcitation process for the photolysis. These features are similar to those reported previously for peroxo complexes. The mechanism of evolution of oxygen reported earlier appears to be the same in all these solids.  相似文献   

16.
Vibrational spectra of compounds of divalent Group 14 elements ElII(OCH2CH2NMe2)2 with ElII = Ge (1), Sn (2), Pb (3) and ClElIIOCH2CH2NMe2 with ElII = Ge (4) and Sn (5) were measured for the first time and analyzed within the framework of DFT calclations. Monomeric compounds 1 and 2 whose molecules are stabilized only through intramolecular coordination were confirmed to be isostructural. Unlike 1 and 2, plumbylene 3 is a polymer in both solution and the crystalline state; the latter was confirmed by X-ray diffraction analysis. The νs C-N stretching frequency in the CH2NMe2 fragment was shown to decrease by 80–100 cm−1 owing to the formation of the coordination bond El←N. To elucidate the mechanism of a dynamic flip-flop process suggested earlier based on the broadening of some signals in the NMR spectra of compounds 1 and 4, the Raman spectra of solutions of compounds 1 and 2 in THF and Py were obtained. These experiments revealed no equilibrium with participation of a stable form with one coordination bond El←N cleaved along with the starting molecule. This is consistent with the results of the corresponding quantum chemical calculations of thermo-dynamic parameters. A somewhat different, more probable mechanism of the dynamic process was proposed, which involves an overturn of the CH2NMe2 fragment with cleavage of the El←N bond in the transition state only.  相似文献   

17.
Methylpalladium(II) dithiolate complexes of the type [PdMe(SS)(ER3] (SS = S2 CNR2 (R = Me or Et), S2COEt, S2P(OR)2 (R = Et, nPr, iPr), S2PPh2; ER3 = PMePh2, PPh3, AsPh3) have been synthesized by the reaction of [Pd2Me2(μ-Cl)2(PMePh2)2] with sodium/potassium/ammonium salts of the dithio acid or by treatment of [PdMeCl(cod)] with ER3 followed by sodium/potassium/ammonium salts of the dithio ligand. All the complexes were characterized by elemental analysis, IR and nuclear magnetic resonance (1H, 31P) data.  相似文献   

18.
Three new sodium cobalt (nickel) selenite compounds, namely, Na2Co2(SeO3)3, Na2Co1.67Ni0.33(SeO3)3, and Na2Ni2(SeO3)3 have been hydro-/solvothermally synthesized in the mixed solvents of acetonitrile and water. Single-crystal X-ray diffraction analyses reveal that these isostructural compounds belong to the orthorhombic Cmcm space group and their structures feature three-dimensional open frameworks constructed by the two-dimensional layers of [MSeO3] pillared by the [SeO3]2− groups. The two different types of Na+ ions reside in the intersecting two-dimensional channels parallel to the a- and c-axes, respectively. Their thermal properties have been investigated via TGA-DSC. The magnetic measurements indicate the existence of the antiferromagnetic interactions in these compounds.  相似文献   

19.
Double-bond migration of allylic alcohols and allylic alkyl ethers was catalytically effected with trans-Mo(N2)2(dpe)2(dpe = Ph2PCH2CH2PPh2). Decarbonylation occurred simultaneously in the case of allyl alcohol. Diallyl ether and allyl phenol ether gave the fragmentation products presumably through initial oxidative addition of the allylO bond. Allylamine was converted to N-propylideneallylamine and NH3. N,N-Dimethylallylamine was isomerized to N-trans-propenyldimethylamine, which was further transformed into 4-dimethylamino-1,3-hexadiene and dimethylamine on addition of oxygen. The catalytic allylation of methyl acetoacetate with allylic ethers and amines was achieved by use of trans-Mo(N2)2(dpe)2.  相似文献   

20.
MMe5(dmpe) (M = Nb or Ta, dmpe = Me2PCH2CH2PMe2) reacts with H2 (500 atm) and dmpe in THF at 60°C to give MH5(dmpe)2? NbH5(dmpe)2 readily reacts with two mol of CO or ethylene (L) to give NbHL2(dmpe)2. The exchange of the hydride ligand with the ethylene protons in NbH(C2H4)2(dmpe)2 is not rapid on the 1H NMR time scale (60 MHz) at 95°C.  相似文献   

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