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1.
The title compound, [Nd(C10H16O4)(C10H17O4)(H2O)]n, has a novel Nd–organic framework constructed from sebacic acid (C10H18O4) linkers, the longest aliphatic ligand used to date in lanthanide metal–organic framework compounds. The structure contains edge‐shared chains of NdO8(H2O) tricapped trigonal prisms that propagate in the [100] direction, with Nd—O distances in the range 2.414 (4)–2.643 (4) Å.  相似文献   

2.
[TMPA]4[Si8O20] · 34 H2O ( 1 ) and [DDBO]4[Si8O20] · 32 H2O ( 2 ) have been prepared by crystallization from aqueous solutions of the respective quaternary alkylammonium hydroxide and SiO2. The crystal structures have been determined by single-crystal X-ray diffraction. 1 : Monoclinic, a = 16.056(2), b = 22.086(6), c = 22.701(2) Å, β = 90.57(1)° (T = 210 K), space group C2/c, Z = 4. 2 : Monoclinic, a = 14.828(9), b = 20.201(7), c = 15.519(5) Å, β = 124.13(4)° (T = 255 K), space group P21/c, Z = 2. The polyhydrates are structurally related host-guest compounds with three-dimensional host frameworks composed of oligomeric [Si8O20]8? anions and H2O molecules which are linked via hydrogen bonds. The silicate anions possess a cube-shaped double four-ring structure and a characteristic local environment formed by 24 H2O molecules and six cations (TMPA, [C8H20N2]2+, or DDBO, [C8H18N2]2+). The cations themselves reside as guest species in large, irregular, cage-like voids. Studies employing 29Si NMR spectroscopy and the trimethylsilylation method have revealed that the saturated aqueous solutions of 1 and 2 contain high proportions of double four-ring silicate anions. Such anions are also abundant species in the saturated solution of the heteronetwork clathrate [DMPI]6[Si8O18(OH)2] · 48.5 H2O ( 3 ) with 1,1-dimethylpiperidinium (DMPI, [C7H16N]+) guest cations.  相似文献   

3.
The crystal structure of a new organic cation cyclohexaphosphate, [4-ClC 6 H 4 CH 2 NH 3 ] 4 Li 2 P 6 O 18 .4H 2 O, is reported. It crystallizes in the triclinic system (space group P-1) with the following unit-cell parameters: a = 9.628(8), b = 12.801(9), c = 19.528(6) Å, α = 78.60(4)°, β = 83.00(5)°, β = 89.98(4)°, Z = 2, and V = 2341(3)Å 3 . The structure has been solved using direct methods and refined by least-squares analysis [R 1 = 0.043, wR 2 = 0.108]. The structure can be described as infinite anionic layers with composition of [Li 2 (P 6 O 18 )(H 2 O) 4 ] 4 ? and parallel to the ac plane. The organic groups are located in the accessible voids. The molecules are stabilized by O─H…O and N─H…O types of intermolecular hydrogen bonds in the unit cell in addition to Van der Waals forces.  相似文献   

4.
A 2-D coordination polymer, (C7N4H16)2{NH(CH3)3}[{K(H2O)}4Na(H2O)5{Co4(H2O)2(B-α-PW9O34)2}]·2H2O (1), was hydrothermally synthesized and structurally characterized by IR spectroscopy, elemental analysis, X-ray powder diffraction, and X-ray single-crystal crystallography. Crystal structure analysis shows a triclinic space group Pī with a?=?12.4677(8)?Å, b?=?12.5054(8)?Å, c?=?18.5745(1)?Å, α?=?73.3220(1)°, β?=?87.1890(1)°, γ?=?62.2710(1)°, and V?=?2443.4(3)?Å3. Sandwich-type tetra-cobalt(II)-substituted [Co4(H2O)2(B-α-PW9O34)2]10? of 1 consists of two trivacant Keggin [B-α-PW9O34]9? moieties and a rhomb-like Co4O16 unit. Each sandwich-type polyoxotungstate subunit connects 12 K(1) and K(2) centers from two adjacent 1-D K-chain units resulting in an interesting 2-D layer framework. Magnetic properties of 1 have been investigated.  相似文献   

5.
Tetramethylammonium sodalite, a synthetic species of composition (CH3)4NAlSi5O12, has been obtained in good yield under hydrothermal conditions in the absence of metal cations. Its crystal structure has been determined using accurate powder data since single crystals could not be grown. The structure seems to be body-centered cubic with a = 8.975 Å but the true symmetry is non-cubic (probable space group I4 ). Each cage of the aluminosilicate framework contains one tetramethylammonium ion. The organic cation does not conform to the cubic symmetry of the ideal framework. The methyl groups point to oxygen atoms of the framework, and the short methyl-oxygen distances of 3.06 Å indicate strong C? H … O interaction. The present results indicate beyond doubt that C? H … O hydrogen bonding involving methyl groups can occur in silicates. This is of particular significance in zeolite chemistry and in the interpretation of interlayer distances in organic clay complexes.  相似文献   

6.
Cluster analysis of the crystal structures of paulingite zeolites (Na,Ca0.5,K,K,Ba0.5)10[Al10Si32O84] · 30H2O (PAU, space group Im [`3]\bar 3 m) has been performed by the tiling method with the TOPOS program package. The tetrahedral T framework of PAU with 672 tetrahedra in the translated unit cell with a = 35.1 ? and V = 43 217 ?3 has been completely decomposed into tiles, complementarily connected polycyclic (polyhedral) T clusters. The zeolite structure is represented by an ensemble consisting of nine geometrically different nanoclusters containing 16 to 48 T tetrahedra (the linear dimensions of the nanoclusters are 12 to 18 ?, respectively). The nanoclusters correspond to seven topologically different types of tiles: 48T-grc (2a), 32T-pau (12e), 30T-plg (16f), 24T-phi (24h), 20T-gsm (12d), 16T-opr (6b, 12e), and 16T-oto (24h, 48k). In the tiles, the positions occupied by extraframework cations A = Na+/Ca2+ and B = K+/Ba2+ have been determined. The characteristic arrangement of the Na+/Ca2+ cations only at the centers of the 8T rings has been revealed, and for them a new equivalent position in the 16T-opr (6b) tile has been determined. A common crystal-chemical formula of paulingite family zeolites has been obtained: (A,B0.5)154[T672O1344wH2O; for the two outermost members, this formula takes the form A154[T672O1344wH2O and B77[T672O1344wH2O. The composition of the alkaline Na,K-paulingite A154T672O1344·wH2O = Na82K72[Al154Si518O1344] ·wH2O corresponds to the model of a structure with a maximal (100%) and ordered filling of the A cation positions: in the 16T-oto (24h, 48k) tiles for K+ and in the 20T-gsm (12d), 30T-plg (16f), and 16T-opr (6b, 12e) tiles for Na+. Such a distribution and the overall number of Na and K atoms are in good agreement with the data for synthetic paulingite analogues the (Na87K72TEA15)[Al164Si508O1344wH2O aluminosilicate and (Na84.5K70.5TEA24.7)[Ga179.7Si492.3O1344wH2O gallosilicate.  相似文献   

7.
Non-empirical molecular orbital studies on the relative stabilities of topologically closed ring clusters H8Si4O4, [H8Si3AlO4]? and [H8Si2Al2O4]? modelling building units of zeolite frameworks, have been carried out. According to the calculations, AlOAl type bridges are unstable in doubly negative charged species, but can be stabilized in the presence of cations. This stabilization effect increases with increasing cation charge. Several hypothetical bimolecular cluster equilibria are also discussed.  相似文献   

8.
Polynuclear Cobalt Complexes. II. Preparation and Structure of [(tren) (NH3)Co(O2)Co(NH3) (tren)](SCN)4 · 2H2O The title compound is obtained on oxygenation of [Co(tren)(H2O)2]2+ in 6M aqueous ammonia or by ligand exchange starting from [(NH3)5Co(O2)Co(NH3)5]-(NO3)4. An X-ray structure determination was made. The substance forms monoclinic crystals, space group P21/c, lattice constants a=10,135, b=8,473, c=19,484 Å, β=108,58°, with two formula units in the cell. The final R is 0,066. The binuclear cation has a center of symmetry, so the Co? O? O? Co unit is planar; the Co? O? O angle is 111,5°. The tertiary nitrogen atoms of both chelate groups are cis to the O2 bridge, as found in doubly bridged [(tren)Co(O2,OH)Co(tren)](ClO4)3 · 3H2O. On acidification in solution, the singly bridged cation [(tren) (NH3)CoO2Co(NH3)(tren)]4+ (a) loses the bound O2 completely. But unlike the doubly bridged cation b , the rate of dissociation of a is independent of pH (Fig. 5). At higher pH (8–10) bridging a→b (Fig. 2) occurs. Both reactions must have the same rate determining step, the first order rate constants being of the order of 2 · 10?3 s?1 (25°, 0,35M KCl).  相似文献   

9.
The title cobalt(II) coordination polymer, poly[[diaquacobalt(II)]‐μ4‐3,3′‐(p‐phenylene)diacrylato], [Co(C12H8O4)(H2O)2]n, was obtained by reaction of Co(NO3)2·6H2O and 3,3′‐(p‐phenylene)diacrylic acid (H2L) under hydrothermal conditions. Each CoII cation sits on a centre of inversion and is hexacoordinated by six O‐atom donors in an octahedral geometry. The CoII centres are connected by four centrosymmetric L2− anions, resulting in a three‐dimensional framework structure. The coordinated water molecules and carboxylate O atoms form hydrogen‐bond interactions, stabilizing the structure of the three‐dimensional framework. Topologically, the framework represents a rare example of the three‐dimensional 4‐connected CdSO4 network type. The metal cations and the organic ligand both show in‐plane coordination with respect to the extended structure.  相似文献   

10.
A 1D chain organic–inorganic rare earth coordination polymer Gd0.5H0.5{[Gd(H2O)6] [Gd(H2O)2(DMSO)][α-SiW11O39]}·7H2O has been synthesized by reaction of α-K8SiW11O39·13H2O, HClO4, Gd2O3 with dimethyl sulfoxide (DMSO) and characterized by elemental analysis, IR, UV, ESR spectra and X-ray diffraction. The title compound crystallizes in a monoclinic lattice, P21/c space group, with a?=?23.544(5), b?=?11.527(2), c?=?23.297(5)?Å, β?=?109.05(3)°, V?=?35976(2)?Å3, Z?=?4, R 1?=?0.0838, wR 2?=?0.1300. The neighboring polyanion units {[Gd(H2O)6][Gd(H2O)2(DMSO)][α-SiW11O39]}2? are bridged together forming a 1D chain structure by means of [Gd(H2O)2(DMSO)]3+ ions. The ESR spectra of the title compound at room temperature are composed of eight lines, indicating the strong effect of the crystal field generated by the nearest surrounding ligands of the GdIII cation.  相似文献   

11.
The title compound, K–GaSi–GIS, potassium gallium silicon oxide hydrate, was synthesized hydro­thermally and its crystal structure was determined from data collected on a single crystal of dimensions 10 × 10 × 8 µm at a synchrotron X‐ray source. The compound, which has the aluminosilicate (AlSi) zeolite gismondine (GIS) topology, Ca4[Al8Si8O32]·16H2O, crystallizes in the tetragonal space group I41/a. A disordered distribution of the framework Si/Ga sites leads to higher symmetry of the GIS‐type network compared with the usual monoclinic symmetry in AlSi–GIS. Framework Ga substitution for Al in AlSi–GIS leads to substantial distortion of the crankshaft chains, reducing the effective pore dimensions and suggesting the possibility of pore‐dimension control via partial framework‐cation substitution.  相似文献   

12.
Hydrothermal reaction of K7H[Nb6O19]·13H2O with Na2SiO3·9H2O (220 °C, 24 h) produces a lacunary siliconiobate [Si4Nb16O56]16?, which was isolated as mixed salt NaK8H6[Na@Si4Nb16O56]·26H2O (1). Changing the silicon source to Ph2Si(OH)2 under the same conditions slightly improves the yield of [Si4Nb16O56]16?, which was isolated as K14H[K@Si4Nb16O56]·26H2O (2). Extending the reaction time leads to rearrangement of [Si4Nb16O56]16? into Keggin-type silicododecaniobate [SiNb12O40]16?, which was isolated and characterized as K8H2(Nb2O2)[SiNb12O40]·20H2O (3). The complexes were characterized by X-ray single crystal analysis, elemental analysis, thermogravimetry, 29Si NMR.  相似文献   

13.
An inorganic–organic hybrid compound [Ni4(pzac)4(H2O)8(β-Mo8O26)]·2H2O (1), pzac = 2- pyrazinecarboxylic acid, was synthesized hydrothermally and characterized by IR spectrum, TGA, X-ray single-crystal diffraction. Photoluminescence property has been investigated. In 1 pzac coordinates to Ni1 with a chelating mode and bridges Ni2 forming a one-dimensional undulate chain structure. Ni atom accepts a terminal oxygen atom of [β-Mo8O26]4? anion with a little longer Ni–O distances of 2.685 Å and 2.767 Å. [β-Mo8O26]4? anion links four Ni atoms of four chains, forming a three-dimensional covalent framework. Lattice water molecules fill the vacancies of the framework.  相似文献   

14.
A new form of Y2Si2O7 (diyttrium heptaoxodisilicate) has been synthesized which is isotypic with thortveitite, Sc2Si2O7, and crystallizes in the centrosymmetric space group C2/m, both at 100 and 280 K. The Y3+ cation occupies a distorted octahedral site, with Y—O bond lengths in the range 2.239 (2)–2.309 (2) Å. The SiO4 tetrahedron is remarkably regular, with Si—O bond lengths in the range 1.619 (2)–1.630 (2) Å. The bridging O atom of the Si2O7 pyrosilicate group shows a large anisotropic displacement perpendicular to the Si—O bond. Changes in lattice and structural parameters upon cooling are small with, however, a distinct decrease of the anisotropic displacement of the briding O atom. Structure solution and refinement in the non‐centrosymmetric space group C2 are possible but do not yield a significantly different structure model. The Si—O—Si bond angle of the isolated Si2O7 groups is 179.2 (1)° at 280 K in C2 and 180° per symmetry in C2/m. The C2/m structure model is favoured.  相似文献   

15.
A new organic–inorganic hybrid polyoxoniobate [Cu(1,3-dap)2(H2O)][(H6Nb6O19)2Cu(1,3-dap)2]?·?4(1,3-dap)·20H2O (1) (1,3-dap?=?1,3-diaminopropane) has been synthesized by the diffusion method and structurally characterized by elemental analyses, infrared spectrum, ultraviolet spectroscopy, and single crystal X-ray diffraction. Crystal structure analysis reveals that 1 consists of a dimeric dumbbell anion [(H6Nb6O19)2Cu(1,3-dap)2]2?, a copper coordinated cation, four 1,3-dap ligands and 20 crystal water molecules. Neighboring units are combined via hydrogen bonds forming a 3-D supramolecular framework.  相似文献   

16.
In the title compound, (4‐O2NC6H4)2S2 or C12H8N2O4S2, the mol­ecules lie across twofold rotation axes. A single type of C—H?O hydrogen bond, with C?O = 3.394 (3) Å and C—H?O = 158°, links the mol­ecules into continuous two‐dimensional sheets built from a single type of R44(44) ring. These sheets are linked by aromatic π?π stacking interactions to form a continuous three‐dimensional framework.  相似文献   

17.
The structure of tetrameric tri­phenyl­silanol, C18H16OSi, (I), has been re‐investigated at 120 (2) K. The hydroxyl H atoms were readily located and one of the arene rings is disordered over two closely positioned sets of sites. The mol­ecules are linked into cyclic tetramers, having approximate (S4) symmetry, via O—H?O hydrogen bonds [H?O 1.81–1.85 Å, O?O 2.634 (3)–2.693 (3) Å and O—H?O 156–166°]. At ambient temperature, there are indications of multiple disorder of the phenyl‐ring sites. In bis­(tri­phenyl­silanol) di­methyl sulfoxide solvate, 2C18H16OSi·C2H6OS, (II), the di­methyl sulfoxide component is disordered across a twofold rotation axis in C2/c, and the molecular components are linked by a single O—H?O hydrogen bond [H?O 1.85 Å, O?O 2.732 (2) Å and O—H?O 172°] into three‐mol­ecule aggregates, which are themselves linked into a single three‐dimensional framework by two C—H?π(arene) interactions. In tetrakis­(tri­phenyl­silanol) 1,4‐dioxan solvate, 4C18H16OSi·C4H8O2, (III), the 1,4‐dioxan component lies across an inversion centre in space group P and centrosymmetric five‐mol­ecule aggregates are linked by paired C—H?π(arene) interactions to form molecular ladders.  相似文献   

18.
The adduct 1,6‐di­amino­hexane–1,1,1‐tris(4‐hydroxy­phenyl)­ethane (1/2) is a salt {hexane‐1,6‐diyldiammonium–4‐[1,1‐bis(4‐hydroxyphenyl)ethyl]phenolate (1/2)}, C6H18N22+·2C20H17O3?, in which the cation lies across a centre of inversion in space group P. The anions are linked by two short O—H?O hydrogen bonds [H?O 1.74 and 1.76 Å, O?O 2.5702 (12) and 2.5855 (12) Å, and O—H?O 168 and 169°] into a chain containing two types of R(24) ring. Each cation is linked to four different anion chains by three N—H?O hydrogen bonds [H?O 1.76–2.06 Å, N?O 2.6749 (14)–2.9159 (14) Å and N—H?O 156–172°]. In the adduct 2,2′‐bipyridyl–1,1,1‐tris(4‐hydroxy­phenyl)­ethane (1/2), C10H8N2·2C20H18O3, the neutral di­amine lies across a centre of inversion in space group P21/n. The tris­(phenol) mol­ecules are linked by two O—H?O hydrogen bonds [H?O both 1.90 Å, O?O 2.7303 (14) and 2.7415 (15) Å, and O—H?O 173 and 176°] into sheets built from R(38) rings. Pairs of tris­(phenol) sheets are linked via the di­amine by means of a single O—H?N hydrogen bond [H?N 1.97 Å, O?N 2.7833 (16) Å and O—H?N 163°].  相似文献   

19.
The novel title coordination polymer, {[Cu(C8H4O4)(C10H9N3)]·H2O}n, synthesized by the slow‐diffusion method, takes the form of one‐dimensional zigzag chains built up of CuII cations linked by benzene‐1,3‐dicarboxylate (ipht) anions. An exceptional characteristic of this structure is that it belongs to a small group of metal–organic polymers where ipht is coordinated as a bridging tridentate ligand with monodentate and chelate coordination of individual carboxylate groups. The CuII cation has a highly distorted square‐pyramidal geometry formed by three O atoms from two ipht anions and two N atoms from a di‐2‐pyridylamine (dipya) ligand. The zigzag chains, which run along the b axis, further construct a three‐dimensional metal–organic framework via strong face‐to‐face π–π interactions and hydrogen bonds. A solvent water molecule is linked to the different carboxylate groups via hydrogen bonds. Thermogravimetric and differential scanning calorimetric analyses confirm the strong hydrogen bonding.  相似文献   

20.
In the title compound, C4H12N22+·2C8H7O3?·2CH4O, the cations lie across centres of inversion and are disordered over two orientations with equal occupancy; there are equal numbers of (R)‐ and (S)‐mandelate anions present (mandelate is α‐hydroxy­benzene­acetate). The anions and the neutral water mol­ecules are linked by O—H?O hydrogen bonds [O?O 2.658 (3) and 2.682 (3) Å, and O—H?O 176 and 166°] into deeply folded zigzag chains. Each orientation of the cation forms two symmetry‐related two‐centre N—H?O hydrogen bonds [N?O 2.588 (4) and 2.678 (4) Å, and N—H?O 177 and 171°] and two asymmetric, but planar, three‐centre N—H?(O)2 hydrogen bonds [N?O 2.686 (4)–3.137 (4) Å and N—H?O 137–147°], and by means of these the cations link the anion/water chains into bilayers.  相似文献   

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