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1.
Employing trans-1,4-diaminocyclohexane (trans-1,4-DACH) as a template, a new two-dimensional layered zinc phosphite (C6H16N2)Zn3(HPO3)4H2O (1) has been prepared hydrothermally. Single-crystal X-ray diffraction analysis shows that it crystallizes in the monoclinic space group P21/n with a=10.458(2) Å, b=14.720(3) Å, c=13.079(3) Å, β=97.93(3)°, V=1994.1(7) Å3, Z=4, R1=0.0349 (I>2σ(I)) and wR2=0.0605 (all data). The inorganic layer is built up by alternation of ZnO4 tetrahedra and HPO3 pseudo pyramids forming a 4.6.8-net. The sheet is featured by a series of capped six-membered rings. The diprotonated trans-1,4-DACH molecules reside in the interlayer region and interact with the inorganic network through H-bonds.  相似文献   

2.
Syntheses and structure determination of TbIII and ErIII complexes with nitrilotriacetic acids (nta) are reported. Their crystal and molecular structures, molecular formulas, and compositions were determined by single-crystal X-ray structure analyses and elementary analyses, respectively. The crystal of the (NH4)3[TbIII(nta)2(H2O)]·4H2O complex belongs to the monoclinic crystal system and C2/c space group. Crystal data are as follows: a = 16.357(8) Å, b = 8.552(4) Å, c = 17.390(9) Å, β = 104.748(7)°, V = 2352.6(19) Å3, Z = 4, Mr = 675.32, Dc = 1.932 g·cm−3, μ = 3.112 mm−1, and F(000) = 1368. The final R and Rw are 0.0220 and 0.0494 for 2357 (I > 2σ(I)) unique reflections, R and Rw are 0.0266 and 0.0510 for all 5613 reflections, respectively. The TbIIIN2O7 moiety in the [TbIII(nta)2(H2O)]3− complex anion has a pseudo-monocapped square antiprismatic nine-coordinate structure, in which the eight coordinate atoms (two N and six O) are from two nta ligands and the water molecule is coordinated to the central TbIII ion directly as the ninth coordinate atom. The crystal of the (NH4)3[ErIII(nta)2] complex belongs to the trigonal crystal system and R-3c space group. Crystal data are as follows: a = 7.9181(16) Å, b = 7.9181(16) Å, c = 54.27(2) Å, γ = 120°, V = 2946.7(14) Å3, Z = 6, Mr = 597.61, D c = 2.021 g·cm−3, μ = 4.345 mm−1, and F(000) = 1770. The final R and Rw are 0.0295 and 0.0673 for 677 (I > 2σ(I)) unique reflections, R and Rw are 0.0366 and 0.0700 for all 4827 reflections, respectively. The ErIIIN2O6 part in the [ErIII(nta)2]3− complex anion is an eight-coordinate structure with a pseudo-dicapped octahedron, in which the eight coordinate atoms (two N and six O) are from two nta ligands.Original Russian Text Copyright © 2004 by J. Wang, X. D. Zhang, Y. Wang, Y. Zhang, Z. R. Liu, J. Tong, and P. L. Kang__________Translated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 6, pp. 1067–1075, November–December, 2004.  相似文献   

3.
A new form of cobalt succinate has been discovered using high-throughput methods and its structure was solved by single crystal X-ray diffraction. Co7(C4H4O4)4(OH)6(H2O)37H2O crystallizes in the monoclinic space group P21/c with cell parameters: a=7.888(2) Å, b=19.082(6) Å, c=23.630(7) Å, β=91.700(5)°, V=3555(2) Å3, R1=0.0469. This complex structure, containing 55 crystallographically distinct non-hydrogen atoms, is compared to the previously reported nickel phase, characterized using ab initio structure solution from synchrotron powder diffraction data.  相似文献   

4.
Treatment of [(1,5-C8H12)PtCl(X)] (X=Cl, CH3, CH2CMe3) with C2 chiral cyclopentane-1,2-diyl-bis(phosphanes) C5H8(PR2)2, either as racemic mixtures or as resolved enantiomers, afforded the chelate complexes [C5H8(PR2)2Pt(Cl)(X)] (X=Cl: R=Ph (1), N-pip (2), OPh (3); X=CH3: R=Ph (4), N-pip (5), OPh (6); X=CH2CMe3: R=Ph (7), N-pip (8), OPh (9); ‘N-pip’=N(CH2)5), (+)-[(1R,2R)-C5H8{P(OPh)2}2PtCl2] [(R,R)-3], (−)-[(1S,2S)-C5H8{P(OPh)2}2PtCl2] [(S,S)-3], (−)-[(1R,2R)-C5H8(PPh2)2Pt(Cl)(X)], and (+)-[(1S,2S)-C5H8(PPh2)2Pt(Cl)(X)] (X=CH3: (R,R)-4, (S,S)-4; X=CH2CMe3: (R,R)-7, (S,S)-7). Reacting 4, 6, and 7 with AgO3SCF3 led to triflate derivatives [C5H8(PR2)2Pt(X)(OSO2CF3)] [X=CH3: R=Ph (11), OPh (12); X=CH2CMe3: R=Ph (13)] with covalently bonded OSO2CF3 ligands. The unusual Pt2 complex [μ-Cl{C5H8(PPh2)2PtCH3}2]O3SCF3 (14) containing an unsupported single Pt---Cl---Pt bridge was also isolated. In the presence of SnCl2, complexes 1, 3, 4, 6, 7, and 9 are catalysts for the hydroformylation of styrene forming 2- and 3-phenylpropanal together with ethylbenzene. Except for 1, they also catalyze the consecutive hydrogenation of the primary propanals to alcohols. High regioselectivities towards 2-phenylpropanal (branched-to-normal ratios ≥91:9) were obtained in hydroformylations catalyzed by 3 and 4, for which the influence of varied CO/H2 partial pressures, catalyst-to-substrate ratios and different reaction temperatures and times on the outcome of the catalytic reaction was also studied. When tin-modified complexes (R,R)-3, (S,S)-3, and (S,S)-4 were used as optically active Pt(II) catalysts, an only low stereoselectivity for asymmetric hydroformylation (e.e.<18%) was observed. The Pt---Sn complexes [C5H8(PR2)2Pt(CH3)(SnCl3)] [R=Ph (15), OPh (17)], resulting from SnCl2 insertion into the Pt---Cl bonds of 4 or 6, undergo rapid degradation in solution, forming mixtures composed of [C5H8(PR2)2Pt(X)(Y)] with R=Ph or OPh and X/Y=Cl/SnCl3 (16, 18), Cl/Cl (1, 3), and SnCl3/SnCl3 (19, 20), respectively. In the presence of SnCl2, triflate complex 11 also becomes a catalyst for styrene hydroformylation and consecutive hydrogenation of the aldehydes to alcohols. The crystal structures of 11 complexes — 2, 5, 7, 8, 9, 10 (the previously prepared [C5H8{P(N-pip)2}2Pt(CH2CMe3)2]), 13, 14, 16, (R,R)-3, and (S,S)-3 — were determined by X-ray diffraction.  相似文献   

5.
A new layered tin(II) phosphate [Sn2(PO4)2]2−[C2N2H10]2+·H2O was synthesized by hydrothermal technique. It crystallizes in monoclinic space groupP21/c(No. 14) with lattice parametersa=9.4112(1) Å;b=8.5998(1) Å;c=15.9921(2) Å;β=100.009(1)°;V=1274.61(2);Z=4;R=2.06%;Rw=2.17%. The structure consists of inorganic layers, comprising a network of strictly alternating SnO3and PO4moieties and held together by strong hydrogen bonding between the layers. Protonated ethylenediamine and water molecules are trapped between the layers.  相似文献   

6.
The interaction of optically pure 1R,2R-diammoniumyclohexane mono-(+)-tartrate and 1S,2S-diammoniumcyclohexane mono-(−)-tartrate with 2 equiv. of o-(diphenylphosphino)benzaldehyde in the presence of 2 equiv. of potassium carbonate in a refluxing ethanol/water mixture gave the optically pure condensation products N,N′-bis[o-(diphenylphosphino)benzylidene]-1R,2R-diiminocyclohexane[1R,2R-cyclohexyl-P2N2, (R,R)-I] and N,N′-bis[o-(diphenylphosphino)benzylidene]-1S,2S-diiminocyclohexane [1S,2S-cyclohexyl-P2N2, (S,S)-I], respectively, in good yield. Reduction of optically pure (R,R)-I and (S,S)-I with NaBH4 in ethanol gave the optically pure reduced products N,N′-bis[o-(diphenylphosphino)benzylidene]-1R,2R-diaminocyclohexane[1R,2R-cyclohexyl-P2N2H4, (R,R)-II] and N,N′-bis[o-diphenylphosphine)benzylidene]-1S,2S-diaminocyclohexane[1S,2S-cyclohexyl-P2N2H4, (S,S)-II], respectively, in good yield. The coordination behaviour of I and II toward salts of CuI and AgI have been examined. The interaction of [Cu(C)3CN)4][X] (X = ClO4, PF6) with 1 equiv. of optically pure L4 [L4 = (R,R)-I, (S,S)-I, (R,R)-II and (S,S)-II] gave the corresponding optically pure [CuL4][X] complexes, III–VI IIIa, L4 = (R,R)-I, X = PF6 IIIb, L4 = (R,R)-I, X = ClO4 IV, X = PF6; Va, L4 = (R,R)-II, X = PF6, Vb L4 = (R,R)-II, X= ClO4, VI L4 = (S,S)-II, X = PF6, in good yield. For the CuI complexes, the L4 ligand acted as a tetradentate ligand. However, a variable-temperature 31P[1H] NMR study of IIIb shows that at ambient temperature one of the imino groups of the tetradentate ligand undergoes rapid dissociation to form a tridentate ligand. The interaction of AgBF4 with 1 equiv. of otpically pure L4 [L4 = (R,R)-I, (S,S)-I, (R,R)-II and (S,S)-II gave the corresponding optically pure [AgL4][BF4] complexes, VII–X VII L4 = (R,R)-I; VIII, L4 = (S,S)-I; IX,L4 = (R,R)-II; X, L4 = (S,S)-II], in good yield. For the AgI complexes, the L4 ligand acted as a tetradentate ligand with the two amino groups coordinated unsymmetrically to the silver. A variable temperature 31P [1H] NMR study of VII suggests that at high temperature the complex exists as a tri-coordinated complex. The structurers of IV and IX were established by X-ray diffraction studies.  相似文献   

7.
A series of homodinuclear Pt compounds containing the anionic, potentially terdentate NCN ligand (NCN=[C6H3(Me2NCH2)2-2,6]) or its 4-ethynyl derivative were prepared. The two platinum centres are linked together in two different fashions: (i) directly linked by an ethynyl or diethynylphenyl group (head-to-head) and (ii) indirectly bonded by a ethynyl- or butadiynyl-linked bis-NCN ligand (tail-to-tail). The reaction of the head-to-head σ,σ′-ethynylide complex {Pt}CC{Pt} ({Pt}=[Pt(C6H3{CH2NMe2}2-2,6)]+) with [CuCl]n yields {Pt}Cl and [Cu2C2]n, while with [Cu(NCMe)4][BF4] a Cu(I) bridged complex was formed: [(η2-{Pt}CC{Pt})2Cu][BF4]. The results of cyclic voltammetry experiments reveal that both connection modes of the two platinum centres lead to electrochemically independent Pt–NCN units. The X-ray crystal structure analysis of the neutral, tail-to-tail bridging butadiyne bis-NCNH ligand [C6H3(CH2NMe2)-1,3-(CC)-5]2 is reported.  相似文献   

8.
The [Cp2HfH2Al(H)Br(OBu)]2 complex (1) was prepared by the reaction of Cp2HfBr2 with AlH3 in THF and characterized by X-ray crystallography. The formation of dinuclear complex 1 proceeds through the intermediate formation (as a result of cleavage of THF molecules) of the >Al(μ-OBu)2Al< fragment. The latter is linked to two hafnocene dihydride molecules by the Hf-H-Al hydrogen bridges. The Hf atom in complex 1 has a 16-electron environment.__________Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 10, pp. 2082–2085, October, 2004.  相似文献   

9.
Physicochemical analysis (XRPA, DTA) was used to study phase equilibria in a ternary salt system Rb2MoO4-Fe2(MoO4)3-Hf(MoO4)2 in the subsolidus region. Ternary molybdates with compositions 5:1:3, 5:1:2, and 1:1:1 have been found and synthesized. Crystal and thermal characteristics have been determined. Single crystals of the ternary molybdate Rb5FeHf(MoO4)6 with a composition of 5:1:2 were grown. The crystal structure of the compound was solved using X-ray diffractometry (CAD-4 automatic diffractometer, MoK α radiation, 1766 F(hkl), R = 0.0298). Hexagonal crystals with unit cell dimensions: a = b = 10.124(1) Å, c =15.135(3) Å, V = 1343.4(4) Å3, Z = 2, ρcalc = 4.008 g/cm3, space group P63. The mixed three-dimensional framework of the structure is formed from two sorts of MoO4 tetrahedra and Fe and Hf octahedra linked through their common O-vertices. Rubidium atoms of three varieties occupy the large voids of the framework.Original Russian Text Copyright © 2004 by B. G. Bazarov, R. F. Klevtsova, A. D. Tsyrendorzhieva, L. A. Glinaskaya, and Zh. G. Bazarova__________Translated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 6, pp. 1038–1043, November–December, 2004.  相似文献   

10.
Two new potassium vanadium phosphates have been prepared and their structures have been determined from analysis of single crystal X-ray data. The two compounds, K3(VO)(V2O3) (PO4)2(HPO4) and K3(VO)(HV2O3)(PO4)2(HPO4), are isostructural, except for the incorporation of an extra hydrogen atom into the nearly identical frameworks. The structures consist of a three-dimensional network of [VO]n chains connected through phosphate groups to a [V2O3] moiety. Magnetic susceptibility experiments indicate that in the case of the di-hydrogen compound, there are no significant magnetic interactions between the three independent vanadium (IV) centers. Crystal data: for K3(VO)(V2O3)(PO4)2 (HPO4), Mr = 620.02, orthorhombic space group Pnma (No. 62), a = 7.023(4) Å, b = 13.309(7) Å, c = 14.294(7) Å, V = 1336(2) Å3, Z = 4, R = 5.02%, and Rw = 5.24% for 1238 observed reflections [I > 3σ(I)]; for K3(VO)(HV2O3)(PO4)2(HPO4), Mr = 621.04, orthorhombic space group Pnma (No. 62), a = 6.975(3) Å, b = 13.559(7) Å, c = 14.130(7) Å, V = 1336(1) Å3, Z = 4, R = 6.02%, and Rw = 6.34% for 1465 observed reflections [I > 3σ(I)].  相似文献   

11.
陶明  熊伟  陈华  李贤均 《催化学报》2006,27(12):1107-1110
 合成了(R,R)-1,2-二苯基乙二胺((R,R)-DPEN)、 钌和三苯基膦的三元配合物RuCl2[P(C6H5)3]2-(R,R)-DPEN, 并将其用于萘乙酮的不对称加氢反应. 考察了碱/催化剂的摩尔比、反应温度和氢气压力等对催化活性和对映选择性的影响. 结果表明,多种因素对反应的转化率和对映选择性均有影响. 在萘乙酮:(CH3)3COK:催化剂摩尔比为 50000:450:1, 氢气压力为4 MPa, 反应温度为25 ℃的条件下,反应16 h时,萘乙酮生成α-萘乙醇的产率和对映选择性分别达到了100%和83%.  相似文献   

12.
The hydrothermal synthesis, single crystal structure, and some physical properties of Ba2(VO2)(PO4)(HPO4)·H2O, a new barium vanadium(V) phosphate hydrate, are reported. This phase is built up from one-dimensional chains of unusual VO5trigonal bipyramids and (H)PO4tetrahedra, fused together via V–O–P linkages. These anionic chains propagate along the polar [010] direction. 11-Coordinate barium cations and water molecules occupy the interchain regions and link the chains together. Structural data for this phase and other known barium vanadium phosphates are briefly compared. Crystal data: Ba2(VO2)(PO4)(HPO4)·H2O,Mr=566.57, monoclinic, space groupP21(No. 4),a=5.0772(5) Å,b=8.724(2) Å,c=10.806(1) Å,β=90.795(8)°,V=478.6(1) Å3,Z=2,R=2.65%,Rw=2.89% [147 parameters, 1893 observed reflections withI>3σ(I)].  相似文献   

13.
The equilibrium of protonation of tetraazamacrocyclic complex of gold(III) [AuL]+ (L = 5,7,12,14-tetramethyl-1,4,8,11-tetraazacyclotetradeca-4,6,11,13-tetraenato(2-)) in a water solution has been investigated. A monoprotonated tetraazamacrocyclic metallocomplex with two inequivalent (iminate and imine) six-membered chelate cycles and charge 1- was obtained and isolated for the first time. The compound [AuHL](ClO4)2 was characterized by chemical analysis, IR and UV-VIS spectroscopy, powder and single crystal X-ray diffraction. The proton was shown to be attached to the β-carbon of one of the two six-membered chelate rings of the macrocycle. Crystal data for [AuHL](ClO4)2 are: a = 7.693(1) Å, b = 17.366(2) Å, c =15.172(2) Å; β = 96.82(1)°, V = 2012.6(4) Å3, Z = 4, d calc = 2.123 g/cm3, space group P21/c. The structure is built from practically planar [Au(C14H23N4)]2+ cations and perchlorate anions [ClO4].Original Russian Text Copyright © 2004 by V. A. Afanasieva, I. V. Mironov, L. A. Glinskaya, R. F. Klevtsova, and L. A. Sheludyakova__________Translated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 6, pp. 1059–1066, November–December, 2004.  相似文献   

14.
Treatment of the vanadium(II) tetrahydroborate complex trans-V(η1-BH4)2(dmpe)2 with (trimethylsilyl) methyllithium gives the new vanadium(II) alkyl cis-V(CH2SiMe3)2(dmpe)2, where dmpe is the chelating diphosphine 1,2-bis(dimethylphosphino)ethane. Interestingly, this complex could not be prepared from the chloride starting material VCl2(dmpe)2. The CH2SiMe3 complex has a magnetic moment of 3.8 μB, and has been characterized by 1H NMR and EPR spectroscopy. The cis geometry of the CH2SiMe3 complex is somewhat unexpected, but in fact the structure can be rationalized on steric grounds. The X-ray crystal structure of cis-V(CH2SiMe3)2(dmpe)2 is described along with that of the related vanadium(II) alkyl complex trans-VMe2(dmpe)2. Comparisons of the bond distances and angles for VMe2(dmpe) 2, V---C = 2.310(5) Å, V---P = 2.455(5) Å, and P---V---P = 83.5(2)° with those of V(CH2SiMe3)2(dmpe)2, V---C = 2.253(3) Å, V---P = 2.551(1) Å, and P ---V---P = 79.37(3)° show differences due to the differing trans influences of alkyl and phosphine ligands, and due to steric crowding in latter molecule. The V---P bond distances also suggest that metal-phosphorus π-back bonding is important in these early transition metal systems. Crystal data for VMe2(dmpe)2 at 25°C: space group P21/n, with a = 9.041(1) Å, b = 12.815(2) Å, c = 9.905(2) Å, β = 93.20(1)°, V = 1145.8(5) Å3, Z = 2, RF = 0.106, and RwF =0.127 for 74 variables and 728 data for which I 2.58 σ(I); crystal data for V(CH2SiMe3)2(dmpe)2 at −75°C: space group C2/c, with a = 9.652(4) Å, b = 17.958(5) Å, c = 18.524(4) Å, β = 102.07(3)°, V= 3140(3) Å3, Z = 4, RF = 0.033, and RwF = 0.032 for 231 variables and 1946 data for which I 2.58 σ(I).  相似文献   

15.
Mixed-ligand complexes [Ni(4-NH2Py) (i-Bu2PS2)2] (I) and Ni(4-NH2Py)2(i-Bu2PS2)2 (II) have been synthesized. Single crystals were grown and X-ray diffraction data (CAD-4 diffractometer, MoK α radiation, 1477 F hkl , R = 0.0320) were used to determine the structure of I. The crystals are orthorhombic: a = 10.675(1) Å; b = 21.681(2) Å; c = 26.302(4) Å, V = 6087.5(12) Å3, Z = 8, ρ(calc) = 1.247 g/cm3, space group Pbca. Complex I possesses a mononuclear molecular structure. The coordination polyhedron of the Ni atom is a tetragonal pyramid NS4 whose base is formed by four S atoms of two cyclic bidentate ligands i-Bu2PS 2 and the axial position is occupied by the N atom of the 4-NH2Py cycle. According to electron spectroscopy data, complex II has an octahedral N2S4 environment of the Ni atom.Original Russian Text Copyright © 2004 by T. E. Kokina, L. A. Glinskaya, E. A. Novoselova, R. F. Klevtsova, and S. V. Larionov__________Translated from Zhurnal Strukturnoi Khimii, Vol. 45, No. 5, pp. 899–904, September–October, 2004.  相似文献   

16.
The title compounds have been prepared in water by reaction of SbF3 with dihydrogen phosphates or arsenates and characterized by single crystal X-ray work, IR, Raman, and Mössbauer spectroscopy. They have identical layer structures. Layers of composition [(SbF)XO4] (X = P, As) were formed by sharing four corners between XO4 tetrahedra and SbFO4 pseudooctahedra. The lengths of the terminal Sb---F bond (with the lone pair in a trans-position) and the Sb---O bonds are 192 and 219 pm, respectively. The stacking of the layers and the interlayer distance depend on the cations and the number of intercalated water molecules. In Na(SbF)AsO4 the Na+ ion is coordinated by only two oxygen atoms within 300 pm. Crystal data: Na(SbF)PO4 · 5H2O, monoclinic, P21/m, A = 656.2(5), B = 654.1(5), C = 867.9(3) pm, β = 92.43(1)°, 889 reflections, 81 parameters, R = 0.044, Rw = 0.046. NH4(SbF)PO4 · H2O, tetragonal, I4/m, A = 656.6(3), C = 1439.8(5) pm, 680 reflections, 31 parameters, R = 0.023, Rw = 0.021. Na(SbF)AsO4, tetragonal, P4/ncc, A = 671.8(1), C = 1756.4(4) pm, 1056 reflections, 28 parameters, R = 0.052, Rw = 0.065. NH4(SbF)AsO4 · 3H2O, tetragonal, P4/ncc, A = 683.8(2), C = 1873.0(7) pm, 1194 reflections, 30 parameters, R = 0.042, Rw = 0.050.  相似文献   

17.
[C4H9)4N]2[Mo2O7] reacts with a variety of organic species containing α-diketone groups to give tetranuclear complexes of general composition [RMo4O15X]3−. The complexes [(C4H9)4N]3[(C9H4O)Mo4O15(OCH3)] (I), [(C4H9)4N]3[(C14H10)Mo4O15(C6H5CO2)] (11) and [(C4H9)4N]3[(C14H8)Mo4O15(OH)] (III) were synthesized from the reactions of dimolybdate with ninhydrin, benzil and phenanthraquinone, respectively. Complex II may also be prepared from dimolybdate and benzoin in acetonitrile-methanol solution, from which it co-crystallizes with the binuclear species [(C4H9)4N]2[Mo2O5(C6H5C(O)C(O)C6H5)2] · CH3CN · CH3OH (IV). Complexes I–III exhibit the tetranuclear core, previously described for the α-glyoxal derivatives [(C4H9)4N]3[(HCCH)Mo4O15X], where X = F or HCO2. The ligands may be formally described as diketals, formed by insertion of ligand carbonyl subunits into molybdenum-oxygen bonds. The structures I–III differ most dramatically in the identity and coordination mode of the anionic ligand X which occupies a position opposite the diketal moiety relative to the [Mo4O11]2+ central cage. Thus, I exhibits a doubly bridging methoxy group in this position, while II possesses a benzoate ligand with an unusual μ3-O,O′coordination mode. Complex III presents a hydroxy-group unsymmetrically bonded to three of the molybdenum centres. The stereochemical consequences of the various coordination modes are discussed. Crystal data: Compound I, monoclinic space group Pc, a = 24.888(2), b = 12.897(3), c = 24.900(3) Å, β = 101.94(2)°, Dcalc = 1.28 g cm−1 for Z = 4. Structure solution and refinement based on 8695 reflections with Fo 6σ(Fo) (Mo-Kα, λ = 0.71073 Å) converged at a conventional discrepancy factor of 0.060. Compound II, orthorhombic space group Pbca, a = 20.426(6), b = 26.916(6), c = 32.147(7) Å, V = 17673.2(20) Å3, Dcalc = 1.33 g cm−3 for Z = 8; 5224 reflections, R = 0.076. Compound III, tetragonal space group I41/a, a = b = 48.129(6), c = 13.057(2) Å, V = 30246.2(12) Å3, Dcalc = 1.35 g cm−3 for Z = 16; 5554 reflections, R = 0.053. Compound IV, orthorhombic space group Pnca, a = 16.097(4), b = 16.755(4), c = 25.986(7) Å, V = 7008.1(13) Å3, Z = 4, Dcalc = 1.18 g cm−3 ; 2944 reflections, R = 0.061.  相似文献   

18.
Crystal structures of chelate compounds Ni[(iso-C4H9)2PS2]2 (I) and Pd[(iso-C4H9)2PS2]2 (II) have been determined by X-ray diffraction: diffractometer X8-APEX, MoK α∔ -radiation, 1048 F hkl , R = 0.0544 for I and CAD-4 diffractometer, MoK α∔ -radiation, 1283 F hkl , R = 0.0347 for II. The crystals are rhombic: a = 12.921(5) Å, b = 17.094(5) Å, c = 22.971(5) Å; V = 5074(3) Å3, Z = 8, calc = 1.250 g/cm3, space group Pbca for I and a = 13.312(3) Å, b = 16.130(7) Å, c = 23.171(5) Å; V = 4975(3) Å3, Z = 8, ρcalc = 1. 208 g/cm3, space group Pbca for II. The structures of I and II are formed by discrete mononuclear molecules. Coordination cores MS4 (M = Ni, Pd) approach planar square configurations. Original Russian Text Copyright ? 2005 by L. A. Glinskaya, T. G. Leonova, T. E. Kokina, R. F. Klevtsova, and S. V. Larionov __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 46, No. 4, pp. 715–720, July–August, 2005.  相似文献   

19.
Crystals with uncommon composition NaBa6[Co(Edta)]4(ClO4)9 · 30H2O (Edta4− is ethylenediaminetetraacetic acid anion) were obtained with the following unit cell parameters: a = 14.8513(9) Å, b = 26.2361(15) Å, c = 15.1789(9) Å, α = 91.661(7)°, β = 113.035(7)°, γ = 89.897(7)°, space group P1¯. Each complex anion [Co(Edta)] is bonded through the carboxyl O atoms to five Ba atoms to give three-dimensional framework in a crystal. One perchlorate ion forms Ba-O-Cl-O-Ba bridge between the Ba atoms; four ClO 4 ions are isolated, while the remaining four ions act as monodentate ligands at the Ba atoms. The water molecules (25 in sum) complete the coordination sphere of the Ba atoms to eight-, nine-, or ten-vertex polyhedron. Four water molecules are in the closest surrounding of the Na atom, one H2O molecule is isolated.__________Translated from Koordinatsionnaya Khimiya, Vol. 31, No. 8, 2005, pp. 590–595.Original Russian Text Copyright © 2005 by Zabel, Poznyak, Pawlowski.  相似文献   

20.
The new (Nb2W4O19),TMA2, Na4(OH2)14(SO4) has been evidenced as a minor phase during the Nb2W4O19TMA (tetramethylammonium) salt synthesis. Its crystal structure has been refined from single crystal X-ray diffraction data, system monoclinic, a=10.166(5) Å, b=17.93(1) Å, c=24.81(1) Å, β=93.057(7)°, space group (S.G.) C2/c, Z=4, R1=3.96%, wR1=4.50%. It shows the stacking of cationic and anionic bidimensional layers. The anionic layer of formula [(Nb2W4O19), TMA2 ]2− is formed of isolated Lindqvist HPAs surrounded by TMA groups. The isolated layers adopt a trigonal symmetry that is lost in the crystal by the association of the cationic sheets. These later, of formula [Na4(OH2)14(SO4)]2+ form porous net-like sheets with nearly circular cavities of diameter 7.5 Å. groups host the available cavities in a disordered manner. The cohesion between the sheets is performed by both electrostatic interactions and a set of hydrogen bonds. In the cationic layers, the highly symmetrical surrounding of HPAs by TMA groups yields a homogeneous electrostatic field at their external surface leading to a statistic Nb/W disorder over the three available independent metallic positions. Then, XAS experiments at the L1/L3-W edge complementarily helped to highlight the preferential cis configuration of (Nb2W4O19)4− anions, help to the strong Nb vs W contrast in their contribution to the backscattering paths. Previously to these experiments, it was of course checked that both the two phases present in the prepared sample contain Nb2W4O19 anions with nearly unchanged geometry.  相似文献   

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