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1.
Sodium neodymium silicate NaNd9(SiO4)6O2 with the apatite structure has been synthesized and studied by X-ray diffraction and scanning electron microscopy. No sodium oxide sublimation occurred during ceramic synthesis by the selected method. The Rietveld method shows that sodium atoms in the structure are ordered (in the 4f position). The O(4) oxygen atoms, which are not involved in silicate ions, are positioned in the centers of triangles formed by Nd(2) atoms. Rather long Nd-Nd distances (3.940 Å) indicate a possible existence of luminescent properties.  相似文献   

2.
The crystal structures of two novel phyl­losilicates with compositions Cs[Si3O6(OH)] (caesium hydroxo­hexa­oxotetra­otri­silicate) and Rb[Si2O4(OH)] (rubidium hydroxo­hexa­oxotetrao­di­silicate) have been characterized by X‐ray diffraction. The topology of the caesium phyl­losilicate silica sheet consists of interconnected four‐ and six‐membered rings and thus differs from all of the previously reported phyl­losilicates. The topology of the rubidium phyl­losilicate silica sheet consists of six‐membered rings only, in boat conformations, resulting in a corrugated sheet similar to that observed in δ‐Na2Si2O5. Both of the title compounds exhibit the characteristic sandwich structure of sheet silicates, with the Cs atom ninefold coordinated and the Rb atom eightfold coordinated to the framework O atoms.  相似文献   

3.
In the crystal structure of the title compound {systematic name: bis­[6‐methyl‐1,2,3‐oxa­thia­zin‐4(3H)‐one 2,2‐dioxide(1−)‐κ2N3,O4]bis­(3‐meth­yl­pyridine)copper(II)}, [Cu(C4H4NO4S)2(C6H7N)2], the CuII centre resides on a centre of symmetry and has an octa­hedral geometry that is distorted both by the presence of four‐membered chelate rings and because of the Jahn–Teller effect. The equatorial plane is formed by the N atoms of two methyl­pyridine ligands and by the more basic O atoms of the acesulfamate ligands, while the weakly basic N atoms of these ligands are in elongated axial positions with a misdirected valence. The crystal is stabilized by two inter­molecular C—H⋯O inter­actions involving the methyl and CH groups, and the sulfonyl O atoms of the acesulfamate group.  相似文献   

4.
The crystal structures of two new diphosphates, sodium hexamanganese bis­(diphosphate) triphosphate, NaMn6(P2O7)2(P3O10), and potassium hexacadmium bis­(diphosphate) triphosphate, KCd6(P2O7)2(P3O10), confirm the rigidity of the M6(P2O7)2(P3O10) matrix (M is Mn or Cd) and the relatively fixed dimensions of the tunnels extending in the a direction of the unit cell. The compounds are isomorphous; the P2O74? anion and the alkali metal cations lie on mirror planes. Bond‐valence analysis of the bonding details of the atoms found within the tunnels permits a prediction of the conductivity.  相似文献   

5.
Rubidium chromium(III) dioxalate dihydrate [di­aqua­bis(μ‐oxalato)­chromium(III)­rubidium(I)], [RbCr(C2O4)2(H2O)2], (I), and dicaesium magnesium dioxalate tetrahydrate [tetra­aqua­bis(μ‐oxalato)­magnesium(II)­dicaesium(I)], [Cs2Mg(C2­O4)2(H2O)4], (II), have layered structures which are new among double‐metal oxalates. In (I), the Rb and Cr atoms lie on sites with imposed 2/m symmetry and the unique water molecule lies on a mirror plane; in (II), the Mg atom lies on a twofold axis. The two non‐equivalent Cr and Mg atoms both show octahedral coordination, with a mean Cr—O distance of 1.966 Å and a mean Mg—O distance of 2.066 Å. Dirubid­ium copper(II) dioxalate dihydrate [di­aqua­bis(μ‐oxalato)­copper(II)­dirubidium(I)], [Rb2Cu(C2O4)2(H2O)2], (III), is also layered and is isotypic with the previously described K2‐ and (NH4)2CuII(C2O4)2·2H2O compounds. The two non‐equivalent Cu atoms lie on inversion centres and are both (4+2)‐coordinated. Hydro­gen bonds are medium‐strong to weak in the three compounds. The oxalate groups are slightly non‐planar only in the Cs–Mg compound, (II), and are more distinctly non‐planar in the K–Cu compound, (III).  相似文献   

6.
In the title compound, [Cu(C6H4NO3)2(H2O)2], the CuII ion lies on an inversion centre and has an elongated octahedral environment, equatorially trans‐coordinated by two N,O‐bidentate picolinate ligands and axially coordinated by two water O atoms. The complex mol­ecules form layers, which are linked by O—H⋯O hydrogen bonds between the aqua ligands and neighbouring carboxyl­ate groups. An intramolecular hydrogen bond between the coordinated carboxyl­ate O atom and the hydroxy H atom is also observed.  相似文献   

7.
The mol­ecule of the title compound {systematic name: di‐μ‐sulfido‐bis[di­aqua(1,4,7,10,13,16‐hexaoxa­cyclo­octade­cane‐κ6O)barium(II)] bis­[1,2‐benzisothiazol‐3(2H)‐one 1,1‐dioxide]}, [Ba2S2(C12H24O6)2(H2O)4](C7H5NO3S)2, lies on an inversion centre. The BaII atom encapsulated by the 18‐crown‐6 ring is coordinated by the six O atoms of the crown, two water O atoms and two bridging S atoms. The four‐membered ring composed of the BaII atoms and the bridging S atoms makes a dihedral angle of 67.1 (1)° with the crown‐ether ring. The aromatic ring system of the saccharin moiety is essentially planar. The packing is built up from layers of the mol­ecules and is stabilized by three intermolecular O—H?O hydrogen bonds.  相似文献   

8.
In the title dinuclear acetate‐bridged complex, [Cu2(C2H3O2)3(NCS)(C10H9N3)2], the two Cu atoms are five‐coordinated, with a basal plane consisting of two N atoms of a di‐2‐pyridylamine (dpyam) ligand and two O atoms of two different acetate ligands. The axial positions of these Cu atoms are coordinated to N and O atoms from thio­cyanate and acetate mol­ecules, respectively, leading to a distorted square‐pyramidal geometry with τ values of 0.30 and 0.22. Both CuII ions are linked by an acetate group in the equatorial–equatorial positions and have synanti bridging configurations. Hydrogen‐bond inter­actions between the amine H atom and the coordinated and uncoordinated O atoms of the acetate anions generate an infinite one‐dimensional chain.  相似文献   

9.
We present the first example of a compound containing Ba2+, C2O42−, water and some additional halide or pseudo‐halide anions, viz. hexa‐μ2‐aqua‐μ6‐oxalato‐dibarium(II) diiso­thio­cyanate, {[Ba2(C2O4)(H2O)6](NCS)2}n. The structure consists of positively charged planar covalent layers of Ba2+ cations, oxalate anions and water mol­ecules. The first coordination sphere of the Ba2+ cation contains six water mol­ecules and four O atoms from two planar oxalate anions. The oxalate anion lies on an inversion centre and is coordinated to six Ba2+ cations, each donor O atom being bonded to two cations. Pairs of water mol­ecules are coordinated by two Ba2+ cations. The layers are interspersed with non‐coordinated NCS anions.  相似文献   

10.
A new polynuclear titanium(IV) complex, dichloro­deca‐μ2‐oxo‐hexa­kis­(penta­methyl­cyclo­penta­dien­yl)hexa­titanium(IV), [Ti6(C10H15)6Cl2O10], has been synthesized by hydro­lysis of a titanium complex bearing an N‐(2‐hydr­oxy‐3,5‐dimethyl­benz­yl)diethano­lamine Mannich ligand. The mol­ecule has two O‐bridged Ti3O3 rings linked to two similar rings through a tetra­hedrally O‐coordinated Ti atom. All Ti atoms except the central one are coordinated to penta­methyl­cyclo­penta­dien­yl (Cp*) ligands. The Cp* ligands are arranged with approximate symmetry with respect to the Ti/O/Cl core.  相似文献   

11.
The crystal structures of two new quaternary compounds, viz. dicerium orthosilicate selenide and dicerium orthosilicate telluride, Ce2(SiO4)Q (Q = Se or Te), have been determined from single‐crystal X‐ray diffraction data. Each structure comprises infinite chains of SiO4 tetrahedra separated by Ce and Q atoms. The site symmetries are Ce m and 2, Si 2 and Qm. The O atoms are in general positions.  相似文献   

12.
The three title complexes, namely pentasodium tris(2,2′‐oxydi­acetato)­neodymium(III) bis­(tetra­fluoro­borate) hexahydrate and its samarium(III) and gadolinium(III) analogues, (I)–(III), respectively, are isomorphous and isostructural and have crystallographic D3 symmetry. The lanthanide metal ions are nine‐coordinate, binding to three O atoms of three oxodi­acetate ligands. One Na+ ion is octahedrally coordinated to six O atoms and the other Na+ ion is octahedrally coordinated to four O atoms and two F atoms. The structure is effectively an infinite three‐dimensional polymer, consistent with the exceptional crystal quality. The racemic solutions spontaneously resolve on crystallization. For the individual crystals selected for structural analysis, the Nd and Sm complexes have the Λ configuration, while the Gd complex has the Δ configuration. The lanthanide–oxy­gen distances show the expected contraction of ca 0.02 Å with increasing atomic number for the lanthanide metal.  相似文献   

13.
The title compound, poly­[[[di­aqua(μ‐4,4′‐bipyridyl)­di­nickel(II)]‐bis(μ‐4,4′‐bipyridyl)‐di‐μ‐hexa­oxo­di­vana­date(2?)] 2.5‐hydrate], [Ni2­(V2O6)2­(C10H8N2)3­(H2O)2]·­2.5H2O, has been prepared hydro­thermally and characterized by elemental analyses, IR spectroscopy and single‐crystal X‐ray diffraction. The structure consists of [V2O6], [Ni­(4,4′‐bipy)4O2] and [Ni­(H2O)2­(4,4′‐bipy)2O2] polyhedra, and water of crystallization. The Ni atoms and one bipyridyl group lie on centres of symmetry.  相似文献   

14.
In catena‐poly­[[[tri­aqua­cadmium(II)]‐μ‐acetyl­enedi­carboxyl­ato‐κ4O,O′:O′′,O′′′] hydrate], {[Cd(C4O4)(H2O)3]·­H2O}n, the CdII atom is coordinated by two bidentate carboxyl­ate groups and three water mol­ecules, thus forming a sevenfold coordination polyhedron with all atoms located on general sites. These polyhedra are connected by the bifunctional acetyl­enedi­carboxyl­ate ligands, forming zigzag chains running parallel to [120]. Hydro­gen bonds, which involve the non‐coordinated water mol­ecule, connect these chains to form a three‐dimensional framework.  相似文献   

15.
In the title compound [systematic name: tri­aqua(1,4,7,10,13,16‐hexaoxa­cyclo­octa­decane‐κ6O)(2‐nitro­phenolato‐κO)­barium(II)–aqua(1,4,7,10,13,16‐hexaoxa­cyclo­octa­decane‐κ6O)‐ bis(2‐nitro­phenolato‐κ2O,O′)­barium(II)–2‐nitro­phenolate (1/1/1)], [Ba(C12H24O6)(C6H4NO3)(H2O)3][Ba(C12H24O6)(C6H4NO3)2(H2O)](C6H4NO3), the two BaII atoms encapsulated by the 18‐crown‐6 rings have different coordinations. Although both BaII atoms are coordinated to the six O atoms of the crowns, in the neutral moiety, the BaII atom is coordinated to one terminal O atom from a water mol­ecule, two phenolate O atoms and two nitro‐group O atoms, while in the cationic moiety, the BaII atom is coordinated to three terminal O atoms from water mol­ecules and one phenolate O atom. Both the crowns are eclipsed and translated along the b direction. In the asymmetric unit, the three components are interconnected by four O—H?O interactions. The packing is stabilized by two intermolecular C—H?O interactions and by one O—H?O interaction.  相似文献   

16.
Four strontium(II) salts with organic acids have been studied. Poly[diaquadi‐μ‐ibuprofenato‐strontium(II)] or poly­[diaqua­bis[μ‐2‐(4‐isobutyl­phen­yl)­propionato]­strontium(II)], [Sr(C13H17O2)2(H2O)2]n, crystallizes with eight‐coordinated Sr atoms. The coordination polyhedra are inter­connected by edge‐sharing to form chains. The Sr coordination chains are packed into layers, which are stacked by van der Waals inter­actions. Poly[μ‐aqua‐diaquadi‐μ‐malonato‐distrontium(II)], [Sr2(C3H2O4)2(H2O)3]n, crystallizes with nine‐coordinated Sr atoms three‐dimensionally inter­connected into a framework structure. One of the two crystallographically independent water mol­ecules is located on a twofold axial site. catena‐Poly[[diaqua­(ascorbato)strontium(II)]‐μ‐ascorbato], [Sr(C6H7O6)2(H2O)2]n, crystallizes with isolated eight‐coordinated Sr polyhedra. One of the ascorbate ligands bridges two Sr atoms, forming zigzag polyhedral ascorbate chains. These chains are tied together by a three‐dimensional hydrogen‐bonding network. Poly[aqua‐μ‐2‐oxidobenzoato‐strontium(II)], [Sr(C7H4O3)(H2O)]n, crystallizes with eight‐coordinated Sr atoms. The polyhedra are inter­connected by face‐ and edge‐sharing into layers. These layers are stacked by van der Waals forces between the protruding 2‐oxidobenzoate ligands.  相似文献   

17.
Single crystals of sodium tetra­calcium trivanadium dodeca­oxide were prepared by melting a powder sample of NaCa4(VO4)3 at 1673 K, followed by slow cooling to room temperature. The compound crystallizes in the Pnma space group and is isostructural with the mineral silicocarnotite, Ca5(PO4)2SiO4. The structure is composed of isolated VO4 tetra­hedra linked by sodium and calcium cations disordered over eight‐ and seven‐coordinated sites.  相似文献   

18.
In the title compound, catena‐poly­[[[tri­aqua­copper(II)]‐μ‐acetyl­enedi­carboxyl­ato‐κ2O:O′′] hydrate], {[Cu(C4O4)(H2O)3]·H2O}n, the CuII ion is coordinated by two monodentate carboxyl­ate groups in trans positions and three water mol­ecules, thus forming a fivefold coordination polyhedron that can be described as a distorted square pyramid. All atoms are located on general sites. The polyhedra are connected by bifunctional acetyl­ene­di­carboxyl­ate ligands, to form almost linear chains parallel to [001]. Hydro­gen bonds involving the non‐coordinated water mol­ecule connect these chains to form a three‐dimensional framework.  相似文献   

19.
Sodium indium(III) chromate(VI) dihydrate, NaIn(CrO4)2·2H2O, synthesized from an aqueous solution at room temperature, is the first indium(III) member of the large family of compounds with kröhnkite [Na2CuII(SVIO4)2·2H2O]‐type chains. The crystal structure is based on infinite octa­hedral–tetra­hedral [In(CrO4)2(H2O)2] chains along [010], linked via charge‐balancing Na+ cations. The slightly distorted InO4(H2O)2 octa­hedra are characterized by a mean In—O distance of 2.125 Å. The CrO4 tetra­hedra are strongly distorted (mean Cr—O = 1.641 Å). The Na atom shows an octa­hedral coordination, unprecedented among compounds with kröhnkite‐type chains. The NaO6 octa­hedra share opposite edges with the InO4(H2O)2 octa­hedra to form infinite [001] chains. The hydrogen bonds are of medium strength. NaIn(CrO4)2·2H2O belongs to the structural type F2 in the classification of Fleck, Kolitsch & Hertweck [Z. Kristallogr. (2002), 217 , 435–443], and is isotypic with KAl(CrO4)2·2H2O and MFe(CrO4)2·2H2O (M = K, Tl or NH4). All atoms are in special positions except one O atom.  相似文献   

20.
The structure of a new synthetic compound, di­ammonium tetra­hydroxy­deca­borate monohydrate, has been determined by single‐crystal X‐ray diffraction. It crystallizes in triclinic space group and all atoms occupy general sites. The title compound is composed of [B10O15(OH)4]4− ions as the fundamental building blocks, and these are linked end‐to‐end by sharing two common O atoms, thus producing infinite chains of composition [B10O14(OH)4]n2n. These chains are linked by hydrogen bonds, thus forming borate sheets. Water mol­ecules and ammonium ions between these sheets connect adjacent sheets via hydrogen bonds.  相似文献   

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