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1.
S.Candeloro de Sanctis N.V. Pavel L. Toniolo 《Journal of organometallic chemistry》1976,108(3):409-421
For the class of compounds mentioned in the title it is difficult to the stucture unambiguously on the molecular and crystal structure of CH3-p)]2 by single crystal X-ray analysis. The crystal data are: M == 743 a.m.u. Space group P21/c. a = 8.510(2), b = 40.652(9), c = 9.762(2) Å, β = 103.61(2)° Dc = 1.50 g/cm3. R = 0.041, R = 0.060, based on 3978 independent reflections. The two π-allylpalladium residues are bridged azenido groups, gaining an approximate square planar coordination around each heavy atom. The two allyl units are stereochemically equivalent, with the central carbon atoms pointing outwars. The rigid triazenido groups force the two palladium atoms into close contact (2.86 Å). The aromatic rings are somewhat rotated with respect to the bonded NNN planes, but some π-conjugation over the whole ligand is still retained. 相似文献
2.
β-CaNi5D0.77 is orthorhombic (a = 8.6033(13) b = 5.0810(9) c = 7.8557(15)Å, Pmcm, Z = 4, Dx = 6.48 g cm?3, V = 343.4Å3, FW = 1339.8 amu. Rietveld analysis of a neutron powder-diffraction pattern shows that D atoms occupy the centers of [Ni4Ca2] square dipyramids (“octahedra”) linked through the Ca atoms at opposite apices and forming chains. About 80% of the deuterium atoms occupy fairly regular sites (DNi = 1.53, 1.80, 1.86, 1.86 Å; DCa = 2.42, 2.45 Å). The remaining 20% occupy very distorted sites (DNi = 1.21, 1.38, 2.07, 2.07 Å; DCa = 2.54, 2.60 Å). The average DD distance in a chain is 4.3 Å. 相似文献
3.
Reaction of tellurium(IV) with excess phenylenethiourea(2-mercaptobenzimidazole) in aqueous methanolic hydrochloric acid leads to the formation of Te(II) complex, tetrakis(phenylenethiourea)tellurium(II) chloride dihydrochloride. The characterisation and crystal structure of the complex are reported. The crystals are monoclinic, space group P21/c, a = 13.939(5), b = 26.523(9), c = 4.873(2) Å, β = 100.29(4)°, V = 1772.6 Å3, M = 872.4, Dc = 1.651 g cm?3, Z = 2, F(000) = 868, μ(MoKα) = 1.298 mm?1. Final R = 0.055 and RW = 0.056 for 918 independent reflections. The tellurium atom in the molecule lies at the crystallographic centre of symmetry and is bonded to four phenylenethiourea sulphur atoms in a square planar arrangement with TeS(1) = 2.678(6), TeS(2) = 2.674(5) Å and S(1)TeS(2) is 90.5(3)°. The ligand behaves as a thione. Chlorine atoms remain outside the coordination sphere of the Te and stabilise the packing arrangement in the unit cell through hydrogen bondings to nitrogen atoms. 相似文献
4.
Na2Mn2S3 was prepared by reacting manganese powder with an excess of anhydrous sodium carbonate and elemental sulfur at 870 K. Extraction of the solidified melt with water and alcohol yielded well developed, bright red crystals. Na2Mn2S3 crystallizes with a new monoclinic structure type, space group , with a = 14.942(2)Å, b = 13.276(2)Å, c = 6.851(2)Å, and β = 116.50(1)°. The crystal structure was determined from single crystal diffractometer data and refined to a conventional R value of 0.026 for 1613 observed reflections. The atomic arrangement shows sulfur-manganese-sulfur slabs which are separated from each other by corrugated layers of sodium atoms. A prominent feature of the crystal structure is the formation of short, four-membered zigzag chains built up by MnS4 tetradedra sharing edges. These chains are further connected by the remaining apices to form an infinite sheet. Short MnMn distances (3.02 and 3.05 Å, respectively) are found within the four membered chains. Susceptibility measurements show antiferromagnetic interactions between the Mn atoms. 相似文献
5.
R. Brec G. Ouvrard M. Evain P. Grenouilleau J. Rouxel 《Journal of solid state chemistry》1983,47(2):174-184
PV2S10 was obtained by heating the elements in stoichiometric proportions at 490°C in evacuated Pyrex tubes. The crystal symmetry is monoclinic, space group , with the unit cell parameters a = 12.734(8)Å, b = 7.349(7)Å, c = 23.662(4)Å, β = 95°22(1), V = 2205(4)Å3, and Z = 8. The structure was solved from 2269 independant reflexions, and anisotropic least squares refinement gave R = 0.036 with 236 variables. The structure can be described as made of [V2S12] units forming endless chains themselves linked, two by two, by [PS4] tetrahedra. In these units each vanadium is surrounded by eight sulfur atoms (mean dVS = 2.459Å) arranged in a distorted bicapped triangular prism. Two of these prisms shared a rectangular face to form [V2S12] groups, in which intercationic distances implied vanadium-vanadium bonds (mean dVV = 2.852(2)Å). Between the infinite double chains, only SS weak van der Waals' bonds exist. More than two thirds of the sulfur atoms are present as [SS]?II pairs, (mean dSS = 2.015Å); the rest are S?II anions. 相似文献
6.
Kjell Waltersson 《Journal of solid state chemistry》1979,28(1):121-131
The crystal structure of has been determined and refined on the basis of three-dimensional X-ray diffractometer data (MoKα radiation). The structure is monoclinic, a = 7.710(2), b = 19.474(7), c = 7.216(2)Å, β = 116.75(1)°, V = 967.5Å3, Z =8, space group Cc (No. 9). The final R and Rw were 0.0295 and 0.0300, respectively, for 1356 independent reflections and 117 variables.The structure contains two crystallographically different VOF5 octahedra linked so as to form complex chains. Two non-equivalent octahedra share one FF edge, forming V2O2F8 doublets. Two F atoms, connected to different V atoms within the doublet, form an edge in the adjacent equivalent V2O2F8 unit thus continuing the chain. The VO distances are 1.583(7) and 1.595(7) Å. The VF distances are in the range 1.881-2.205 Å, mean value: 1.989 Å. The H2O group is a crystal water molecule. 相似文献
7.
NH3(MoO3)3 crystallizes with hexagonal symmetry, space group , lattice constants a = 10.568 Å, c = 3.726 Å, and Z = 2. The crystal structure has been determined by Patterson synthesis and refined assuming isotropic temperature factors to a final conventional R value of 0.085. The structure shows a three-dimensional arrangement built up of double chains of distorted MoO6 octahedra, parallel to the [001] direction. The octahedral double chains are linked among each other through common oxygen atoms. In addition to the shared oxygen atoms, each molybdenum is coordinated to one terminal oxygen. MoO distances range from 1.645 to 2.378 Å and OMoO angles from 74.3 to 114.3°. These results are consistent with the fact that molybdenum in high-valence states shows octahedral coordination with terminal oxygens. 相似文献
8.
The structure of Rh2(CH3CO2)4(DMF)2 {DMF = HCON(CH3)2} has been determined by single crystal X-ray methods. The compound crystallizes with eight formula units in a cell of dimensions: a = 29.438(7) Å, b = 7.978(2) Å, c = 20.279(5) Å, β = 113.20(4)°, V = 4377.5 Å3, space group C2/c. The structure has been refined by full-matrix least-squares method to a final R = 0.030 for the 4156 observed data. Two Rh(II) atoms are linked by four acetate groups forming a dimeric unit, where the RhRh distance is 2.383(1) Å. The coordination sphere about each Rh atom is completed by a DMF molecule; the average RhO(DMF) distance is 2.296(3) Å. 相似文献
9.
Hydrocarbon solutions of Mo2(O—t-Bu)6 and PF3 (2 equiv) yield Mo4F4(O—t-Bu)8, I, and PF2(O—t-Bu). Compound I contains a bisphenoid of molybdenum atoms with two short MoMo distances, 2.26 Å, and four long MoMo distances, 3.75 Å, corresponding to localized MoMo triple bonding and non-bonding distances, respectively. The tetranuclear compound may be viewed as a dimer, [Mo2(μ2-F)2(O-t-Bu)4]2, and addition of PMe3 to hydrocarbon solutions of I yields Mo2F2(O—t-Bu)4(PMe3)2, II, which contains an unbridged MoMo triple bond of distance 2.27 Å. Each molybdenum atom is coordinated to two oxygen atoms, one fluorine atom and the phosphorus atom of the PMe3 ligand in a roughly square planar manner. The overall central Mo2O4F2P2 skeleton has C2 symmetry and NMR studies (1H, 19F and 31P) are consistent with the maintenance of this type of structure in solution. Infrared and electronic absorption spectral data are reported. These are the first compounds containing fluorine ligands attached to the (MoMo)6+ unit. 相似文献
10.
The complex dicarbonylbis(diphenylethylphosphine)platinum, Pt(CO)2[P(C6H5)2(C2H5)]2, crystallizes in either of the enantiomorphous space groups P3121 (No. 152) and P3221 (No. 154) with cell dimensions a = 10.64(1), c = 22.06(1) Å, U = 2163 Å3; pc = 1.564 g/cm3 for Z = 3, pm = 1.55(3) g/cm3. The intensities of 1177 independent reflections have been determined by counter methods with MoKα monochromatized radiation. The structure has been solved by the heavy atom method. The refinement, carried out by full-matrix least squares down to a final R factor of 0.042, has enabled the absolute configuration of the crystal sample (space group P3121) to be ascertained. The molecule is roughly tetrahedral, and has the metal atom lying on a two-fold axis of the cell. Bond parameters are: PtC = 1.92(2) Å, PtP = 2.360(4) Å, CPtC = 117(1)° and PPtP = 97.9(2)°. The PtC2 and PtP2 moieties make a dihedral angle of 86.0(3)°. The overall C2 symmetry of the molecule is probably only a statistically averaged situation, a disorder in the PtCO interactions being apparent from the orientations of the thermal ellipsoids of the C and O atoms. 相似文献
11.
Paul S. Haradem Bertrand L. Chamberland Lewis Katz Alain Gleizes 《Journal of solid state chemistry》1977,21(3):217-223
A single crystal study of Ba3Pt2O7 shows that the structure tolerates a variable composition which can be written Ba3Pt2+xO7+2x. The crystal studied has a hexagonal cell of dimensions a = 10.108 ± 0.006 Å and c = 8.638 ± 0.009 Å, and a probable space group . The density determined by water displacement is 7.99 g/cm3; the theoretical density for Ba3Pt2O7 is 7.94 g/cm3. The structure was determined from the set of 401 observed independent reflections obtained from 5189 reflections measured by automated counter methods. Refinement on F was carried to a conventional R of 8.0%. The structure has barium-oxygen layers with an essentially four-layer stacking sequence of the double hexagonal (ABAB) type. Platinum is found mainly in face-sharing octahedra, but is also distributed over some sites in which the coordination is nearly square planar and other sites in which the coordination is trigonal prismatic with three PtO bond lengths of 2.00 Å and three long PtO distances of 2.65 Å. The platinum with planar coordination is 0.08 Å from the plane of the four oxygen atoms. 相似文献
12.
Iwami Higashi Nobuhiro Shiotani M. Uda Tadashi Mizoguchi Hiroaki Katoh 《Journal of solid state chemistry》1981,36(2):225-233
The crystal structure of Mg51Zn20, a phase designated conventionally as “Mg7Zn3,” has been determined by the single-crystal X-ray diffraction method. It was solved by the examination of a Patterson synthesis, and refined by the ordinary Fourier and least-squares method; the R value obtained was 4.8% for 1167 observed reflections. The crystal is orthorhombic, space group Immm, with a = 14.083(3), b = 14.486(3), c = 14.025(3) Å, and Z = 2. There are 18 independent atomic sites, Zn1Zn6, Mg1Mg10, A, and B, and the last two sites are statistically occupied by Zn and Mg atoms with the occupancies; 0.46(2)Zn7 + 0.52(2)Mg11 and 0.24(2)Zn8 + 0.74(2)Mg12, for A and B, respectively. The structure of the crystal is described as an arrangement of icosahedral coordination polyhedra, to which all the atomic sites but Zn3 site belong. In this arrangement the Zn atoms other than the Zn3 and Zn8(B) center the icosahedral coordination polyhedra with coordination number 12. The Zn3, Zn8 atoms, and all the Mg atoms except Mg11(A) are located at the centers of various coordination polyhedra with the coordination numbers from 11 to 15. The distances between neighboring atoms are 2.71–3.07, 2.82–3.65, and 2.60–3.20 Å for ZnZn, MgMg, and ZnMg, respectively. 相似文献
13.
The crystal structure of NbS3 was determined from single-crystal diffractometer data obtained with MoKα radiation. The compound is triclinic, space group , with: a 4.963(2) Å; b = 6.730(2) Å; c = 9.144(4)Å; α = 90°; β = 97.17(1)°; γ = 90°. The structure is closely related to the ZrSe3 structure type; it shows that the compound can be formulated as Nb4+(S2)2?S2?, in agreement with XPS spectra. The main difference with ZrSe3 is that the Nb atoms are shifted from the mirror planes of the surrounding bicapped trigonal prisms of sulfur atoms to form NbNb pairs (NbNb = 3.04 Å); this causes a doubling of the b axis relative to ZrSe3 and a decrease of the symmetry to triclinic. 相似文献
14.
Ba2V2O7 is triclinic with a = 13.571(3), b = 7.320(2), c = 7.306(2) Å, α = 90.09(1), β = 99.48(1), β = 99.48(1), γ = 87.32(1)°, V = 7.15.1 Å3, Z = 4, and space group . The crystal structure was solved by Patterson and Fourier methods and refined by full-matrix least-squares analysis to a Rw of 0.034 (R = 0.034) using 2484 reflections measured on a Syntex automatic four-circle diffractometer. The structure has two unique divanadate groups that are repeated by the b and c lattice translations to form sheets of divanadate groups parallel to (100). These sheets are linked by four unique Ba atoms that lie between these sheets. Ba(1) and Ba(3) are coordinated by eight oxygens arranged in a distorted biaugmented triangular prism and a distorted cubic antiprism, respectively. Ba(2) is coordinated by 10 oxygens arranged in a distorted gyroelongated square dipyramid and Ba(4) is coordinated by nine oxygens arranged in a distorted triaugmented triangular prism. These coordination numbers are substantiated by a bond strength analysis of the structure, and the variation in 〈BaO〉 distances is compatible with the assigned cation and anion coordination numbers. Both divanadate groups are in the eclipsed configuraton with 〈VO(br)〉 bond lengths of 1.821(4) and 1.824(4) Å and VO(br)V angles of 125.6(3) and 123.7(3)°, respectively. Examination of the divanadate groups in a series of structures allows certain generalizations to be made. Longer 〈VO(br)〉 bond lengths are generally associated with smaller VO(br)V angles. When VO(br)V < 140°, the divanadate group is generally in an eclipsed configuration; when VO(br)V > 140°, the divanadate group is generally in a staggered configuration. Nontetrahedral cations with large coordination numbers require more oxygens with which to bond, and hence O(br) is more likely to be three coordinate, with the divanadate group in the eclipsed configuration. In the eclipsed configuration, decrease in VO(br)V promotes bonding between O(br) and nontetrahedral cations, and hence smaller nontetrahedral cations are generally associated with smaller VO(br)V angles. 相似文献
15.
Kunio Miki Masahiro Yama Yasushi Kai Nobutami Kasai 《Journal of organometallic chemistry》1982,239(2):417-428
The molecular structure of a three-coordinate palladium(II)-styrene complex, [Pd(η5-C5H5)(PEt3)(styrene)]BF4 has been determined by means of X-ray diffraction. The crystal belongs to the monoclinic system, space group P21/c, with four formula units in a cell of dimensions: a 10.229(3), b 11.262(3), c 18.760(5) Å and β 103.77(2)°. The structure was solved by the heavy atom method, and refined by the least-squares procedure to R = 0.050 for 3635 observed reflections. The palladium atom is surrounded by the cyclopentadienyl group, the triethylphosphine ligand and the olefinic bond of styrene in the cationic complex. In the palladiumstyrene bonding, the olefinic bond is inclined by 77.3° to the coordination plane defined by the Pd and P atoms and the center of the cyclopentadienyl ring (PdC(1) 2.176(6), PdC(2) 2.234(5) and C(1)C(2) 1.369(8) Å). 相似文献
16.
Jean Galy Renée Enjalbert Gérard Jugie Joachim Strähle 《Journal of solid state chemistry》1983,47(2):143-150
Cooling of VOCl3 below its melting point (196 K) yields an amorphous phase, which transforms into the crystalline state upon further cooling. The crystallization is accompanied by a remarkable change in color from pale yellow to deep orange. A single crystal has been grown from the amorphous phase. VOCl3 crystallizes in the orthorhombic system, space group Pnma, with lattice parameters a = 4.963(1), b = 9.140(4), c = 11.221(5)Å at 133 K; Z = 4. The 35Cl-NQR experiments show two signals at approximately 11.4 MHz of intensity 2:1, which implies two different crystallographic sites for chlorine atoms, in agreement with the centrosymmetric space group Pnma. The crystal structure exhibits isolated tetrahedral molecules VOCl3 lying on a mirror plane and stacked with their VO axis along [100] to form trigonal prismatic columns. A close relationship exists with the structure of AsBr3, in which the lone pair occupies the position corresponding to the oxygen atoms. 相似文献
17.
The crystal and molecular structure of 3,4-quinoxalino-1-tellura(II)cyclopentane has been determined by X-ray diffraction at room temperature. The crystals are tetragonal, space group I41/a with a = b = 25.315(8), c = 6.010(1) Å and V = 3851.38 Å3. The density of 1.96 g cm?3 calculated on the basis of 16 molecules per unit cell is in agreement with the flotation value of 1.91 g cm?3. The structure has been refined to a conventional R value of 0.0408 using 744 independent observed reflections obtained from four-circle diffractometer measurements. The structure consists of discrete molecules TeC = 2.134 Å (av.), CN = 1.343 Å (av.) and angle CTeC = 80.7° (e.s.d. 0.5) but the intermolecular TeTe bonds (3.791 and 3.998 Å) are less than the sum of the Van der Waals' radii thus indicating the presence of secondary bonding. These short intermolecular contacts in the crystal structure are consistent with the anomalous physical properties observed. 相似文献
18.
R.V Shpanchenko V.V Chernaya J Hadermann C Geibel 《Journal of solid state chemistry》2003,173(1):244-250
The new complex oxide Na2SrV3O9 was synthesized and investigated by means of X-ray diffraction, electron microscopy and magnetic susceptibility measurements. This oxide has a monoclinic unit cell with parameters a=5.416(1) Å, b=15.040(3) Å, c=10.051(2) Å, β=97.03(3)°, space group P21/c and Z=4. The crystal structure of Na2SrV3O9, as determined from X-ray single-crystal data, is built up from isolated chains formed by square V4+O5 pyramids. Neighboring pyramids are linked by two bridging V5+O4 tetrahedra sharing a corner with each pyramid. The Na and Sr atoms are situated between the chains. Electron diffraction and HREM investigations confirmed the crystal structure. The temperature dependence of the susceptibility indicates low-dimensional magnetic behavior with a sizeable strength of the magnetic intra-chain exchange J of the order of 80 K, which is very likely due to superexchange through the two VO4 tetrahedra linking the magnetic V4+ cations. 相似文献
19.
β-TeVO4 crystallizes in the monoclinic system with the space group and the parameters: a = 4.379 Å, b = 13.502 Å, c = 5.446 Å, and β = 91.72°. Vanadium occupies the center of a square pyramid of oxygens, an extra oxygen is at VO = 2.77 Å. These distorted octahedra share corners forming puckered sheets parallel to (010). The sheets are held together by [Te2O6]4? groups in which tellurium is one-side coordinated by four oxygen atoms. 相似文献
20.
The authors have found a new structural type, related to α-PbO2, called tri-α-PbO2. The oxide Fe2WO6 is the prototype. It crystallizes in the orthorhombic system with the following cell parameters: a = 4.576 Å, b = 16.766 Å, and c = 4.967Å. The space group is Pbcn. The structure has been determined by X-ray single-crystal methods and refined by least-squares procedures (R = 0.065).The structure consists of zig-zag chains parallel to the c-axis. Each such chain is built up by MO6 (M = Fe or W) octahedra-sharing edges. The chains are linked together by corner sharing. There are two types of chains: one containing only iron atoms, the other being an ordered 1-1 arrangement of iron and tungsten atoms. 相似文献