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1.
Two novel heterometallic trinuclear incomplete cubane-like clusters [(CH3CH2)4N][{M2CuS4}(edt)2(PPh3)] (M = Mo, W) have been synthesized by reaction of [(CH3CH2)4N]2[M2S4(edt)2] (M = Mo, W) with Cu(PPh3)2(dtp) [where edt is 1,2-ethane-dithiolato ligand, dtp is S2P(OCH2CH3)2]. The two crystals are isomorphous in space group P1 (No. 1). The unit cell contains two independent molecules, but the two discrete anions have the same orientation for the PPh3 ligands along one axis so the space group is undoubtedly non-centrosymmetric. The discrete anion contains two edt ligands and one PPh3 ligand attached to one incomplete cubane-like cluster core {M2CuS4}3+ (M = Mo, W). The bond lengths of Mo---Mo[W---W] and the two Mo---Cu[W-Cu] are 2.852(2)[2.844(1)], 2.802(2)[2.765(3)], 2.760(2)[2.762(3)] Å, respectively. The M 2S4(edt)2 (M = Mo, W) moiety remains almost unchanged, except that for the compound 1 the Mo=S double bond length elongates from av. 2.10 to av. 2.165 Å. The title clusters provide a new type of unsymmetric μ2-bridging sulphido ligand. The incomplete cubane-like cluster core {Mo2CuS4}3+ of compound 1 is distorted because the two Cu---μ2---S bond lengths are significantly different (2.313 Å and 2.409 Å), but the core {W2CuS4}3+ of compound 2 has approximately Cs symmetry. The IR spectra of the two title clusters and two starting materials are assigned.  相似文献   

2.
A mixed-valent molybdenotungstophosphate, Nax(Mo, W)2O3(PO4)2 (x 0.75) has been isolated for the first time. It crystallizes in the space group P 21/m with a = 7.200(1) Å, b = 6.369(1) Å, c = 9.123(1) Å, and β = 106.29(1)°. Its structure consists of M2PO13 units built up of two M O6 octahedra (M = Mo, W) and one PO4 tetrahedron sharing their apices as already observed in several molybdenum phosphates. These units share their apices with PO4 tetrahedra forming [M2P2O15] chains running along . The host lattice [(Mo, W)2P2O11] can be described by the assemblage of such chains or by the assemblage of [MPO8] chains running along , in which one PO4 tetrahedron alternates with one MO6 octahedron. The tridimensional framework [Mo, WP2O11] delimits tunnels running along , occupied by sodium with two kinds of coordination, 6 and 5. The distribution of the different species, in the octahedral sites according to the formulation Na0.75(MoVI0.42WVI0.58)M1 (MoV0.75WVI0.25)2O3(PO4)2, is discussed.  相似文献   

3.
The electronic state of carbon in trigonal prismatic environment in [Re12CS17(CN)6]n complexes with variable redox state n = 6 ↔ 8 was studied by molecular orbital method and electron localization function. The state is characterized by sp2-hybridisation and oxidation state −4. A weak long-distance interaction between μ6-С and μ2-S in the group [(μ6-С)(μ2-S)3] was discovered for n = 6, the interaction disappears for n = 8.  相似文献   

4.
Two new vanadium tellurites, Cu(TATP)V2TeO8 (1) and Cu(DPPZ)V2Te2O10 (2), (TATP=1,4,8,9-tetranitrogen-trisphene, DPPZ=dipyridophenazine) have been synthesized under hydrothermal conditions and structurally characterized by elemental analyses, IR, and single-crystal X-ray diffraction. Compound 1 features an interesting two-dimensional layer structure constructed by [V2TeO8]n double-chain-like ribbons linked by [Cu(TATP)]2+ bridges. Compound 2 consists of two types of chiral layers: one left-handed and the other right-handed, which lead to racemic solid-state compound. In each layer, there exist two types of inorganic helical chains (V4Te4O8)n and (Te2O2)n, with same handedness. Two types of helical chains are linked by μ3(O6) atoms to generate a V/Te/O inorganic anionic layer. The [Cu(DPPZ)]2+ cationic complex fragments are covalently bonded to the layer, projecting below and above the vanadium tellurites layer.  相似文献   

5.
Reaction of the Et3NH+ salts of the [(μ-RS)(μ-CO)Fe2(CO)6] anions (R=But, Ph or PhCH2) with (μ-S2)Fe2(CO)6 gives reactive intermediates [(μ-RS)(μ-S){Fe2(CO)6}24-S)]. Reactions of the latter with alkyl halides, acid chlorides and Cp(CO)2FeI have been studied. X-Ray structure of (μ-ButS)(μ-PhCH2S)[Fe2(CO)6]24-S) was determined.  相似文献   

6.
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   

7.
The bonding in the ethyne adduct W2(μ-C2H2)(μ-ONp)2(ONp)6 (Np=CH2tBu) has been examined by various computational methods [Extended Hückel (EHMO), Fenske–Hall, and Gaussian 92 RHF (Restricted Hartree–Fock) and density functional (Becke-3LYP) calculations] employing the model compound W2(μ-C2H2)(μ-OH)2(OH)6. EHMO and Fenske–Hall calculations suggest, based on total orbital energy, that a μ-parallel ethyne geometry should have the lowest energy, although traditional frontier orbital arguments agree with the observance of a skewed acetylene bridge. Gaussian 92 computations reproduce the non-perpendicular/non-parallel μ-C2H2 geometry in close agreement to that observed in the solid-state (X-ray) structure, which leads us to suggest that the distortion is not sterically imposed by the attendant alkoxide ligands. The observed geometry can be rationalized in terms of Jahn–Teller distortional stabilization from either the μ-parallel or μ-perpendicular mode, i.e., the geometry is favored on electronic grounds, though the potential energy surface is rather shallow. These results are discussed in terms of previous studies of the addition of alkynes to d3–d3 dinuclear complexes of tungsten and in terms of relationships between d2-W(OR)4 and d8-Os(CO)4 fragments.  相似文献   

8.
Three new tetrahedral rhenium cluster compounds [Re4Se4(PMe2Ph)4Br8]·1.5CH2Cl2 (1), [Re4Te4(PMe2Ph)4Br8]·CH2Cl2 (2), and [Re4Te4(PMe2Ph)4Cl8]·CH2Cl2 (3) have been synthesized by the reaction of the corresponding precursor chalcohalide complexes [Re4Q4(TeX2)4X8] (X = Br, Q = Se (for 1), Te (for 2); X = Cl, Q = Te (for 3)) with dimethylphenylphosphine in CH2Cl2. All compounds have been characterized by X-ray single-crystal diffraction and elemental analyses, IR and 31P NMR spectroscopy. 31P NMR spectroscopy indicates the formation of isomers in solution, confirmed by single-crystal X-ray analysis.  相似文献   

9.
The compound [Re2(CO)8(MeCN)2] reacts with diazoindene (C9H6N2) while refluxing in THF to afford three dirhenium products in which C9H6N2 is cleaved with loss of N2 and with incorporation of the residual indenylidene group into the products. Two indenylidene groups are coupled in two diastereomers of [Re2(CO)6(μ,η55-1,1′-C18H12)] where C18H12=bis(indenylidene). X-ray structures show that these isomers are related as RR/SS and RS isomers. These have the two Re(CO)3 groups coordinated transoid and cisoid, respectively to a trans bis(indenylidene) bridge. The third product is the μ-indenylidene complex [Re2(CO)8(μ,η15-C9H6)], which was also structurally characterised by X-ray diffraction.  相似文献   

10.
Treatment of closo-[Ru44-PPh)22-CO)(CO)10] with acetylene under ambient conditions leads to the insertion of the acetylene into the skeletal framework of the cluster and the formation of [Ru44-PPh){μ43-P(Ph)CHCH}(μ2-CO)(CO)10], the structure of which has been determined X-ray crystallographically.  相似文献   

11.
Three rare earth compounds, KEu[AsS4] (1), K3Dy[AsS4]2 (2), and Rb4Nd0.67[AsS4]2 (3) have been synthesized employing the molten flux method. The reactions of A2S3 (A = K, Rb), Ln (Ln = Eu, Dy, Nd), As2S3, S were accomplished at 600 °C for 96 h in evacuated fused silica ampoules. Crystal data for these compounds are: 1, monoclinic, space group P21/m (no. 11), a = 6.7276(7) Å, b = 6.7190(5) Å, c = 8.6947(9) Å, β = 107.287(12)°, Z = 2; 2, monoclinic, space group C2/c (no. 15), a = 10.3381(7) Å, b = 18.7439(12) Å, c = 8.8185(6) Å, β = 117.060(7)°, Z = 4; 3, orthorhombic, space group Ibam (no. 72), a = 18.7333(15) Å, b = 9.1461(5) Å, c = 10.2060(6) Å, Z = 4. 1 is a two-dimensional structure with 2[Eu(AsS4)] layers separated by potassium cations. Within each layer, distorted bicapped trigonal [EuS8] prisms are linked through distorted [AsS4]3− tetrahedra. Each Eu2+ cation is coordinated by two [AsS4]3− units by edge-sharing and bonded to further two [AsS4]3− units by corner-sharing. Compound 2 contains a one-dimensional structure with 1[Dy(AsS4)2]3− chains separated by potassium cations. Within each chain, distorted bicapped trigonal prisms of [DyS8] are linked by slightly distorted [AsS4]3− tetrahedra. Each Dy3+ ion is surrounded by four [AsS4]3− moieties in an edge-sharing fashion. For compound 3 also a one-dimensional structure with 1[Nd0.67(AsS4)2]4− chains is observed. But the Nd position is only partially occupied and overall every third Nd atom is missing along the chain. This cuts the infinite chains into short dimers containing two bridging [As4]3− units and four terminal [AsS4]3− groups. 1 is characterized with UV/vis diffuse reflectance spectroscopy, IR, and Raman spectra.  相似文献   

12.
Mamata Singh  R.J. Butcher  N.K. Singh   《Polyhedron》2008,27(14):3151-3159
Two novel mononuclear mixed-ligand complexes [Ni(en)2(3-pyt)2] (1) and [Cu(en)2](3-pyt)2 (2), derived from potassium [N′-(pyridine-3-carbonyl)-hydrazinecarbodithioate [K+(H2L)] and containing en as a co-ligand, have been synthesized. The [K+(H2L)] undergoes cyclization in the presence of ethylenediamine (en) and is converted to 5-(3-pyridyl)-1,3,4-oxadiazole-2-thione (3-pyt). [Ni(en)2(3-pyt)2] and [Cu(en)2](3-pyt)2 have been characterized with the aid of elemental analyses, IR, UV–Vis, magnetic susceptibility and single crystal X-ray studies. The complexes 1 and 2 crystallize in the orthorhombic and monoclinic systems with space groups Pca2(1) and C2/c, respectively. The single crystal X-ray diffraction studies of both complexes indicate that (3-pyt) adopts a thione form in 1 but is present as a thiolato form in 2.  相似文献   

13.
Treatment of [(ClAu)2(diphosphine)] {diphosphine=bis(diphenylphosphino)methane (dppm), bis(diphenylphosphino)isopropane (dppip), 1,2-bis(diphenylphosphino)ethane (dppe), 1,3-bis(diphenylphosphino)propane (dppp)} with two equivalents of the anion [Fe2(μ-CO)(CO)6(μ-PPh2)] in the presence of TlBF4 gives the new heterometallic diclusters [{Fe2(μ-CO)(CO)6(μ-PPh2)Au}2(diphosphine)] that have been isolated and characterized. Their 31P-NMR spectra show different patterns as a function of the diphosphine ligand. The electrochemical behavior of these compounds has been investigated and compared with that of the mono- [Fe2(μ-CO)(CO)6(μ-PPh2)(μ-AuPPh3)] and tricluster [{Fe2(μ-CO)(CO)6(μ-PPh2)Au}3(triphos)] derivatives.  相似文献   

14.
《Polyhedron》2004,23(18):3143-3146
The title complexes were synthesized in acetone by the reaction of [n-Bu4N]2[MoS4Cu4Cl4] and pzMe2 for compound 1, and n-Bu4NBr, [NH4]2[WS4], CuCl and pzMe2 for compound 2. X-ray diffraction studies of 1 and 2 demonstrate that four of the six edges of the tetrahedral [MS4]2− core are bridged by four copper atoms, giving a pentanuclear structure MS4Cu4(pzMe2)6X2 (M = Mo, W) with the five metal atoms essentially coplanar. The four Cu atoms exhibit two different coordination modes. Each of one pair of mutually trans Cu atoms is coordinated by two (μ3-S) atoms and two nitrogen atoms of pzMe2 rings, giving a distorted tetrahedral CuS2N2 arrangement. The other two mutually trans Cu atoms are coordinated by two (μ3-S) atoms, one nitrogen atom of pzMe2 and one terminal Cl or Br ligand, giving a distorted tetrahedral CuS2NX unit. In addition to being structurally studied by X-ray diffraction, the title compounds have been characterized by IR, UV–Vis and 1H NMR spectroscopy. The IR results, which include low-frequency M–Sb stretching bands, are consistent with the X-ray structural analysis and confirm that the [MS4]2− cores are coordinated through all four sulfur atoms in the complexes 1 and 2.  相似文献   

15.
The reaction of a water solution of K4Re6Te8(CN)6 with a solution of Mn(NO3)2 in 0.02M hydrochloric acid in the presence of DMF gave crystals of a cluster rhenium complex [{ Mn(H2O)2(DMF)}2Re6Te8(CN)6]·2H2O. The structure of the compound was determined by single crystal X-ray diffraction (a = 12.6679(9) Å, b = 17.4524(12) Å, c = 9.7882(6) Å, β = 105.570(6)°, V = 2084.6(3) Å3, Z = 2, space group P21/n, R = 0. 0389). In the complex, the [Re6Te8(CN)6]4− cluster anions are linked to Mn2+ cations by the cyanide bridges, the manganese cations being additionally coordinated by the DMF molecule and two water molecules. The neighboring clusters are joined by Re-C-N-Mn bridges into a three-dimensional framework possessing cavities filled with doubly disordered water molecules.Original Russian Text Copyright © 2004 by Yu. V. Mironov, S. F. Solodovnikov, V. E. Fedorov, and Yu. V. Gatilov__________Translated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 5, pp. 918–922, September–October, 2004.  相似文献   

16.
The first Te–Mn–CO clusters were obtained by the thermal reaction of K2TeO3 with [Mn2(CO)10] in MeOH. The basicity of the μ4-Te ligand in the octahedral cluster anion [(μ4-Te)2Mn4(CO)12]2− is demonstrated by its binding to the fragment [(TeMe2)Mn(CO)4]+ in an axial fashion to afford the novel cluster 1 .  相似文献   

17.
Single-crystal Bi2Te3-Te nanocomposites with heterostructure were synthesized using a two-step solvothermal process in the presence of ethylenediaminetetraacetic acid disodium salt. The first step is the formation of the Te nanorods and the second step is to grow the Bi2Te3 sheets off the Te rods surface to form the Bi2Te3-Te nanocomposites. The products were characterized by X-ray diffraction, scanning electron microscopy and transmission electron microscopy. We demonstrate a method of an epitaxial growth of Bi2Te3 nanosheets perpendicular to the axis of the central Te rod and a formation process of Bi2Te3-Te nanocomposites is also proposed.  相似文献   

18.
The new tetranuclear complexes [Fe3Ln(μ3-O)2(CCl3COO)8(H2O)(THF)3]·THF (Ln = CeIII (1), PrIII (2), NdIII (3)) and [Fe3Ln(μ3-O)2(CCl3COO)8(H2O)(THF)3]·THF·C7H16 (Ln = SmIII (4), EuIII (5), GdIII (6), TbIII (7), DyIII (8), HoIII (9), LuIII (10) and YIII (11)) have been prepared. All compounds were prepared by the reaction between [Fe2BaO(CCl3COO)6(THF)6] and the corresponding LnIII nitrate salt. The crystal structures of 1–4, 8 and 9 have been determined; these isostructural molecules have a non-planar {Fe3Ln(μ3-O)2} “butterfly” core. Magnetic susceptibility measurements show dominant intramolecular antiferromagnetic exchange interactions for all the complexes. 57Fe Mössbauer spectroscopy shows three different environments for the FeIII metal ions, all in their high-spin state S = 5/2 (confirming that no electron transfer from CeIII to FeIII occurs in 1). At the time scale of the Mössbauer spectroscopy (about 10−7 s), evidence of magnetization blocking, i.e. slow relaxation of the magnetization, is observed below 3 K for 7, which was confirmed by ac susceptibility measurements.  相似文献   

19.
The singlet-triplet separations for the edge-sharing bioctahedral (ESBO) complex W2(μ-H)(μ-Cl)(Cl4(μ-dppm)2 · (THF)3 (II) has been studied by 31P NMR spectroscopy. The structural characterization of [W2(μ-H)2(μ-O2CC6H5)2Cl2(P(C6H5)3)2] (I) by single-crystal X-ray crystallography has allowed the comparison of the energy of the HOMOLUMO separation determined using the Fenske-Hall method for a series of ESBO complexes with two hydride bridging atoms, two chloride bridging atoms and the mixed case with a chloride and hydride bridging atom. The complex representing the mixed case, [W2(μ-H)(μ-Cl)Cl4(μ-dppm)2 · (THF)3] (II), has been synthesized and the value of −2J determined from variable-temperature 31P NMR spectroscopy.  相似文献   

20.
Three new ternary potassium(I) zinc(II) or cadmium(II) tellurides, namely, K2Cd2Te3, K6CdTe4 and K2ZnTe2, were synthesized by solid-state reactions of the mixture of pure elements of K, Cd (or Zn) and Te in Nb tubes at high temperature. K2Cd2Te3 belongs to a new structure type and its structure contains a novel two-dimensional [Cd2Te3]2− layers perpendicular to the b-axis. K(5) cation is located at the center of five member rings of the 2D [Cd2Te3]2− layer, whereas other K+ cations occupy the interlayer space. K6CdTe4 with a K6HgS4 type structure features a “zero-dimensional” structure composed of isolated CdTe4 tetrahedra separated by the K+ ions. K2ZnTe2 in the K2ZnO2 structural type displays 1D [ZnTe2]2− anionic chains of edge sharing [ZnTe4] tetrahedra separated by the potassium(I) ions. K2Cd2Te3, K6CdTe4 and K2ZnTe2 revealed a band gap of 1.93, 2.51 and 3.0 eV, respectively.  相似文献   

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