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1.
The crystal structure of K2Cu3(As2O6)2 was determined from single-crystal X-ray data by a direct method strategy and Fourier summations [a = 10.359(4) Å, B = 5.388(2)Å, C = 11.234(4) Å, β = 110.48(2)°; space group C2/m; Z = 2; Rw = 0.025 for 1199 reflections up to sin /λ = 0.81 Å−1]. In detail, the structure consists of As(V)O4 tetrahedra and As(III)O3 pyramids linked by a common O corner atom to [As(V)As(III)O6]4− groups with symmetry m. The bridging bonds As(V)---O [1.749(3) Å] and As(III)---O [1.838(2) Å] are definitely longer than the other As(V)---O bonds [mean 1.669 Å] and As(III)---O bonds [1.764(2) Å, 2×]. The angle As(V)---O---As(III) is 123.0(1)°. The Cu atoms are [4 + 2]- and [4 + 1]-, and the K atom is [9]-coordinated to oxygen atoms. The As2O6 groups and the Cu coordination polyhedra are linked to sheets parallel to (001). These sheets are connected by the K atoms. Single crystals of K2Cu3(As2O6)2 suitable for X-ray work were synthesized under hydrothermal conditions.  相似文献   

2.
The monoclinic compound PbCuAs2O7 [a=5.553 (1),b=8.404 (1),c=13.011 (2) Å, =91.61 (2)° space group P21/n-C 2h 5 ;Z=4] was synthesized under hydrothermal conditions. The structure was solved by direct methods and was refined to anR value of 3.6%. The Pb atom is irregularly eight coordinated by O atoms, and the Cu atom tetragonal pyramidal [4+1] coordinated by O atoms. Each two AsO4 tetrahedra share a common O atom corner building up As2O7 groups. These groups are connected with the CuO4 polyhedra to sheets parallel (101). These sheets are combined by the PbO8 polyhedra to a framework.
Herrn Prof. Dr.K. Komarek zum 60. Geburtstag gewidmet.  相似文献   

3.
The crystal structures of five isotypic hexagonal compounds with general formulaMAs4O6 X [M=K, NH4;X=Cl, Br, I; space group: P622;Z=1] were determined from 370 single crystal X-ray data and refined toR values <0.05. The structure type is characterized by neutral charged [As2O3] sheets arranged parallel (00.1). The As atoms of neighbouring two sheets point to each other and the sheets are combined by interlayeredM andX atoms, respectively. TheM atoms are coordinated to twelve oxygen atoms, theX atoms are coordinated to twelve arsenic atoms. In both cases the coordination polyhedron is a hexagonal prism. The compounds were synthesized by thermal treatments of cubic As2O3 and potassium or ammonium haloids in a saturated aqueous solution of potassium acetate resp. ammonia [500 K, saturation vapour pressure].
Die Verbindungen KAs4O6 X (X=Cl, Br, I) und NH4As4O6 X (X=Br, I): Hydrothermalsynthese und Strukturbestimmung
Zusammenfassung Die Kristallstrukturen der fünf isotypen hexagonalen Verbindungen mit der allgemeinen FormelMAs4O6 X [M=K, NH4;X=Cl, Br, I; Raumgruppe: P622;Z=1] wurden anhand von 370 Einkristall-Röntgendaten bestimmt und aufR-Werte <0.05 verfeinert. Der Strukturtyp ist ausgezeichnet durch neutrale [As2O3]-Schichten, die parallel (00.1) angeordnet sind. Die As-Atome zweier benachbarter Schichten weisen jeweils aufeinander zu, und die Schichten selbst werden durch zwischengelagerteM- bzw.X-Atome verbunden. DieM-Atome werden jeweils von zwölf O-Atomen, dieX-Atome von zwölf As-Atomen umgeben. Das Koordinationspolyeder ist in beiden Fällen ein hexagonales Primsa. Die einzelnen Verbindungen wurden unter Hydrothermalbedingungen aus kubischem As2O3 und dem jeweiligen Kalium- oder Ammoniumhalogenid in einer gesättigten wäßrigen Lösung von Kaliumacetat bzw. Ammoniak synthetisiert (500 K, Sättigungsdampfdruck).
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4.
The structure of di(aquo-O)(pyrazine-2,3-dicarboxylato-N,O; -O′,O′′) calcium(II) hydrate [Ca(2,3-PZDC)(H2O)2·;H2O] contains molecular sheets in which Ca(II) ions are bridged by the carboxylate groups of the ligand molecules. Two bridging paths are evident. In the first, an N,O-bonding moiety formed by a hetero-ring nitrogen atom and the carboxylate oxygen atom nearest to it and both oxygen atoms of the second carboxylic group are active. The second path is formed by the other oxygen atom from the carboxylic group involved in the N,O-bonding moiety and an oxygen atom from the second carboxylic group. The latter atom is bidentate. A two-dimensional molecular pattern is formed. Each Ca(II) ion is also coordinated by two water oxygen atoms, making the number of coordinated atoms eight. The coordination polyhedron is a distorted pentagonal bipyramid with an oxygen atom at the apex on one side of the equatorial plane and two oxygen atoms forming the apices on the other side.  相似文献   

5.
Sm2As4O9: An Unusual Samarium(III) Oxoarsenate(III) According to Sm4[As2O5]2[As4O8] Pale yellow single crystals of the new samarium(III) oxoarsenate(III) with the composition Sm4As8O18 were obtained by a typical solid‐state reaction between Sm2O3 and As2O3 using CsCl and SmCl3 as fluxing agents. The compound crystallizes in the triclinic crystal system with the space group (No. 2, Z = 2; a = 681.12(5), b = 757.59(6), c = 953.97(8) pm, α = 96.623(7), β = 103.751(7), γ = 104.400(7)°). The crystal structure of samarium(III) oxoarsenate(III) with the formula type Sm4[As2O5]2[As4O8] (≡ 2 × Sm2As4O9) contains two crystallographically different Sm3+ cations, where (Sm1)3+ is coordinated by eight, but (Sm2)3+ by nine oxygen atoms. Two different discrete oxoarsenate(III) anions are present in the crystal structure, namely [As2O5]4? and [As4O8]4?. The [As2O5]4? anion is built up of two Ψ1‐tetrahedra [AsO3]3? with a common corner, whereas the [As4O8]4? anion consists of four Ψ1‐tetrahedra with ring‐shaped vertex‐connected [AsO3]3? pyramids. Thus at all four crystallographically different As3+ cations stereochemically active non‐binding electron pairs (“lone pairs”) are observed. These “lone pairs” direct towards the center of empty channels running parallel to [010] in the overall structure, where these “empty channels” being formed by the linkage of layers with the ecliptically conformed [As2O5]4? anions and the stair‐like shaped [As4O8]4? rings via common oxygen atoms (O1 – O6, O8 and O9). The oxygen‐atom type O7, however, belongs only to the cyclo‐[As4O8]4? unit as one of the two different corner‐sharing oxygen atoms.  相似文献   

6.
《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   

7.
The new tetranuclear alkoxide hexa‐μ2‐isopropoxy‐1:2κ4O;1:3κ4O;1:4κ4O‐hexaisopropoxy‐2κ2O,3κ2O,4κ2O‐trialumin­ium(III)­neodymium(III), [Nd{Al(C3H7O)4}3], has a metal–oxy­gen NdAl3O12 core which consists of four metal atoms arranged in an approximately planar triangular geometry. The central Nd atom is six‐coordinated by O atoms and the Al atoms are four‐coordinated by O atoms.  相似文献   

8.
Protonation equilibrium has been studied for the acyclic gold(III) tetraaza metallocomplex [AuB]2+ [B = N, N′-bis(2-aminoethyl)-2,4-pentanediiminato(1−)] in aqueous solution. The synthetic procedure is described. The crystal and molecular structure of the protonated form of the [AuHB](H5O2)(ClO4)4 complex has been determined. Monoclinic crystals with unit cell dimensions a = 11.964(2) Å, b = 13.789(3) Å, c = 15.496(3) Å, β = 109.00(3)°, V = 2417.1(8) Å3, Z = 4, ρcalc = 2.243 g/cm3, space group P21/n. The structure is built of nearly planar [Au(C9H20N4)]3+ complex cations, (H5O2)+ cations, and [ClO4] anions. The gold atom coordinates four nitrogen atoms of the ligand, forming a square plane. The six-membered chelate ring of the ligand is protonated at the central β-carbon atom and contains imine C=N bonds. The oxygen atoms of the perchlorate ions are hydrogen bonded to the (H5O2)+ dihydroxonium ion and to the nitrogen atoms of the NH2 groups of the [AuHB]3+ cation. Original Russian Text Copyright ? 2005 by V. A. Afanasieva, L. A. Glinskaya, R. F. Klevtsova, and I. V. Mironov __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 46, No. 5, pp. 909–915, September–October, 2005.  相似文献   

9.
A novel dimeric polyoxotungstate K4LaH[As2W20CuO67(H2O)3 ]Cl2·22.5H2O has been synthesized and characterized by IR, element analysis TG and cyclic voltammogram. The anion K4LaH[As2W20CuO67(H2O) 3]Cl2·22.5H2O can be characterized as two {AsIIIW9O33}9− moieties linked via a {Cu(OH)}, a {W(H2O)} and a {WO(H2O)} group which total coordination numbers are respectively 5, 5, 6. An additional lanthanide atom connects the dimeric cluster via a W-O-La bond. The X-ray single crystal diffraction shows that it is in the triclinic system, space group P-1, with a = 12.287(6) ?, b = 20.197(1) ?,c=21.483(1)?,α = 62.584(8)°,β = 74.659(8)°,γ = 75.273(9)°,V = 4509(4)?3, Z = 2. To our known, the polyoxotungstate is the novel sandwich-type polyoxoanion, which is decorated by transition-metal and lanthanide atoms at the same time.  相似文献   

10.
Pale yellow single crystals of the composition Ln3X2[As2O5][AsO3] (Ln = Tm for X = Br and Ln = Sm for X = Cl) were obtained via solid-state reactions in the systems Ln2O3/As2O3 from sealed silica ampoules using different halides as fluxing agents. Sm3Cl2[As2O5][AsO3] and Tm3Br2[As2O5][AsO3] crystallize isotypically in the triclinic space group P1 with Z = 2 and cell parameters of a = 543.51(4) pm, b = 837.24(6) pm, c = 1113.45(8) pm, α = 90.084(2)°, β = 94.532(2)°, γ = 90.487(2)° for the samarium and a = 534.96(4) pm, b = 869.26(6) pm, c = 1081.84(8) pm, α = 90.723(2)°, β = 94.792(2)° γ = 90.119(2)° for the thulium compound. The isotypic crystal structure of both representatives exhibits three crystallographically different Ln3+ cations, each with a coordination number of eight. (Ln1)3+ and (Ln2)3+ are only coordinated by three oxygen atoms, whereas (Ln3)3+ shows additional contacts to halide anions in forming square [LnO4X4]9– antiprisms. All As3+ cations are surrounded by three oxygen atoms in the shape of isolated [AsO3]3– ψ1-tetrahedra. They occur either isolated or condensed as pyroanionic [As2O5]4– units with a bridging oxygen atom. In both anions, non-binding lone-pair electrons are present at the As3+ cations with a pronounced stereochemically active function.  相似文献   

11.
Nickel-ammonium tetrametaphosphate, Ni(NH4)2P4O12 · 7H2O is triclinic with a = 13.841(3); b = 9.621(5); c = 7.482(2)Å; α = 98.05(4); β = 97.25(4); γ = 103.01(4)°; M = 536.59; V = 947.9Å3; Z = 2; Dx = 1.879 g cm?3; μ = 14.524 cm?1, and space group P1. The crystal structure was solved using 1661 independent reflections measured on a single-crystal diffractometer (Mo). The final R value is 0.056. The two crystallographic independent nickel atoms Ni(1) and Ni(2) are octahedrally coordinated: Ni(1) by four oxygen atoms and two water molecules, Ni(2) by six water molecules. Ni(1), closely connected to two P4O12 rings, forms a complex anion [Ni(P4O12)2(H2O)2]6? which is associated to ammonium polyhedra and [Ni(H2O)6]2+ octahedra. Another interesting feature of this atomic arrangement is the presence of a large channel (10 × 4) Å2 parallel to the c axis. The internal surface of this channel is covered by six zeolitic water molecules.  相似文献   

12.
The crystal structure of a double salt of sodium and cesium with 2-diphenylacetyl-1,3-indandione of the composition [Cs2Na(H2O)2(C23H16O3)(C23H15O3)3] (I) was studied by X-ray crystallography. The crystals of I are monoclinic, Z = 2, space group P21/n, a = 10.212(2) ?, b = 23.479(5) ?, c = 15.638(3) ?, β = 98.30(03)°. The compound contains [Cs2NaO10] trimers, in which the central Na atom shares two edges with two Cs atoms through deprotonated bridging ligands. The trimers are connected to adjacent trimers by paired C-H...O contacts to form layers. The layers form an infinite open framework via hydrogen bonds between the oxygen atoms of keto groups of noncoordinated indandione moieties and water molecules that enter the cesium coordination sphere in trimers of the adjacent layers.  相似文献   

13.
Yellowish crystals of K2[(UO2)As2O7] ( 1 ) have been synthesized by solid‐state reactions method. The structure of 1 [orthorhombic, Pmmn, a = 12.601(2), b = 13.242(2), c = 5.621(1) Å, V = 937.9(3) Å3, Z = 4] has been solved by direct methods and refined to R1 = 0.049, wR2 = 0.1060 for 1059 observed reflections. The structure of 1 is based upon [(UO2)As2O7]2? sheets formed by corner sharing between [UO6]6? distorted octahedra and [As2O7]4? polyarsenate groups. The K+ cations are either in eightfold or tenfold coordination and are located between the sheets. The topology of the uranyl arsenate sheet is related to silicate minerals of the melilite group and related synthetic silicate, aluminate and germanate compounds.  相似文献   

14.
Cd2Cu(PO4)2     
During an investigation of the insufficiently known system M1O–M2O–X2O5–H2O (M1 = Cd2+, Sr2+ and Ba2+; M2 = Cu2+, Ni2+, Co2+, Zn2+ and Mg2+; X = P5+, As5+ and V5+), single crystals of the novel compound dicadmium copper(II) bis[phosphate(V)], Cd2Cu(PO4)2, were obtained. This compound belongs to a small group of compounds adopting a Cu3(PO4)2‐type structure and having the general formula M12M2(XO4)2 (M1/M2 = Cd2+, Cu2+, Mg2+ and Zn2+; X = As5+, P5+ and V5+). The crystal structure is characterized by the interconnection of infinite [Cu(PO4)2]n chains and [Cd2O10]n double chains, both extending along the a axis. Exceptional characteristics of this structure are its novel chemical composition and the occurrence of double chains of CdO6 polyhedra that were not found in related structures. In contrast to the isomorphous compounds, where the M1 cations are coordinated by five O atoms, the Cd atom is coordinated by six. The dissimilarity in the geometry of M1 coordination between Cd2Cu(PO4)2 and the isomorphous compounds is mostly due to the larger ionic radius of the Cd cation in comparison with the Cu, Mg and Zn cations. Sharing a common edge, two CdO6 polyhedra form Cd2O10 dimers. Each such dimer is bonded to another dimer sharing common vertices, forming [Cd2O10]n double chains in the [100] direction. The Cu atoms, located on an inversion centre (site symmetry ), form isolated CuO4 squares interconnected by PO4 tetrahedra, forming [Cu(PO4)2]n chains similar to those found in related structures. Conversely, the [Cd2O10]n double chains, which were not found in related structures, are an exclusive feature of this structure.  相似文献   

15.
16.
Synthesis and Crystal Structure of the Nitrido Oxalato Osmate PPh4{Na(15-Crown-5)[OsNCl3(C2O4)]} The title compound has been prepared by slow reaction of PPh4[OsNCl4] with sodium oxalate in boiling dichloromethane in the presence of 15-crown-5, forming violet crystals, which were characterized by an X-ray structure determination. Space group P21/c, Z = 4, 4 769 observed unique reflections, R = 0.035. Lattice dimensions at –80°C: a = 1 931.4, b = 1 178.7, c = 1 764.1 pm, β = 99.39°. The structure consists of PPh4+ ions and ion pairs {Na(15-crown-5)[OsNCl3(C2O4)]}?, in which the osmium atom is distortedly octahedrally coordinated by the nitrido ligand, by three chlorine atoms, and by two oxygen atoms of the oxalato group. The remaining oxygen atoms of the oxalato ligand are coordinated to the sodium atom, which, together with the five oxygen atoms of the crown ether molecule, gets coordination number seven.  相似文献   

17.
The dimeric title copper(II) complex, diaqua‐1κO,2κO‐bis[3,9‐dimethyl‐6‐(2‐pyridyl­methyl)‐4,8‐di­aza­undeca‐3,8‐di­ene‐2,10‐dione dioximato(1?)]‐1k4N2,N4,N8,N10;1:2κ5O2:N2,N4,N8,N10‐dicopper(II) diperchlorate, [Cu2(C17H24N5O2)2](ClO4)2, crys­tallizes with one Cu atom in a square‐pyramidal environment and the other Cu atom displaying a distorted octahedral coordination. In each case, the four N atoms in the core of the ligand (two imine and two oxime N atoms) form the base of the pyramid, with a water mol­ecule at an apex. The two parts of the dimer are linked by an interaction [2.869 (2) Å] between one of the Cu atoms and one of the oxime O atoms coordinated to the second Cu atom, and also by a hydrogen bond between the apical water mol­ecule on the second Cu atom and the pyridyl N atom from the coordination sphere of the first Cu atom. The pyridyl N atoms of the lariat arms are not coordinated to either of the Cu atoms. Thus, this potentially pentadentate ligand is only tetradentate when coordinated to CuII.  相似文献   

18.
The one‐ and two‐dimensional polymorphic cadmium polycarboxylate coordination polymers, catena‐poly[bis[μ2‐2‐(2‐methyl‐1H‐benzimidazol‐1‐yl)acetato‐κ3N3:O,O′]cadmium(II)], [Cd(C10H9N2O2)2]n, and poly[bis[μ2‐2‐(2‐methyl‐1H‐benzimidazol‐1‐yl)acetato‐κ3N3:O,O′]cadmium(II)], also [Cd(C10H9N2O2)2]n, were prepared under solvothermal conditions. In each structure, each CdII atom is coordinated by four O atoms and two N atoms from four different ligands. In the former structure, two crystallographically independent CdII atoms are located on twofold symmetry axes and doubly bridged in a μ2N:O,O′‐mode by the ligands into correspondingly independent chains that run in the [100] and [010] directions. Chains containing crystallographically related CdII atoms are linked into sheets viaπ–π stacking interactions. Sheets containing one of the distinct types of CdII atom are stacked perpendicular to [001] and alternate with sheets containing the other type of CdII atom. The second complex is a two‐dimensional homometallic CdII (4,4) net structure in which each CdII atom is singly bridged to four neighbouring CdII atoms by four ligands also acting in a μ2N:O,O′‐mode. A square‐grid network results and the three‐dimensional supramolecular framework is completed by π–π stacking interactions between the aromatic ring systems.  相似文献   

19.
A new cadmium–thiocyanate complex, namely catena‐poly[1‐carboxymethyl‐4‐(dimethylamino)pyridinium [cadmium(II)‐tri‐μ‐thiocyanato‐κ4N:S2S:N] [[[4‐(dimethylamino)pyridinium‐1‐acetate‐κ2O,O′]cadmium(II)]‐di‐μ‐thiocyanato‐κ2N:S2S:N]], {(C9H13N2O2)[Cd(NCS)3][Cd(NCS)2(C9H12N2O2)]}n, was synthesized by the reaction of 4‐(dimethylamino)pyridinium‐1‐acetate, cadmium nitrate tetrahydrate and potassium thiocyanide in aqueous solution. In the crystal structure, two types of CdII atoms are observed in distorted octahedral coordination environments. One type of CdII atom is coordinated by two O atoms from the carboxylate group of the 4‐(dimethylamino)pyridinium‐1‐acetate ligand and by two N atoms and two S atoms from four different thiocyanate ligands, while the second type of CdII atom is coordinated by three N atoms and three S atoms from six different thiocyanate ligands. Neighbouring CdII atoms are linked by thiocyanate bridges to form a one‐dimensional zigzag chain and a one‐dimensional coordination polymer. Hydrogen‐bond interactions are involved in the formation of the supramolecular network.  相似文献   

20.
In the title complex, tetraphenylphosphonium μ4‐nitrato‐κ4Ocyclo‐tetrakis(μ‐acetato‐O:O′)tetra‐μ‐oxo‐tetrakis[oxovana‐dium(V)], the anion lies about a twofold axis and consists of the cyclic [V4O8] unit coordinated by four acetato ligands with interatomic V?V distances of 3.269 (1) and 3.273 (1) Å. The double‐bonded O atom [N=O 1.102 (6) and N—O 1.268 (4) Å] of the nitrato ligand links the four V atoms with V—O bond distances of 2.613 (2) and 2.813 (2) Å. The negative charge of the complex is balanced by tetraphenyl­phosphonium cations occupying the Na positions in the NaCl‐type ionic packing of the structure.  相似文献   

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