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1.
In the compound [Ni(Bptc)2(Bimb)2(H2O)2] (I), where H4Bptc is 3,3′,4,4′-biphenyltetracarboxylic acid; Bimb is 4,4′-bis(1-imidazolyl)biphenyl), Ni(II) has a distorted octahedral coordination geometry, which was bonded with two N atoms from two Bimb ligands, two O atoms from two H2Bptc2− ligands and two water O atoms. The crystal structure of compound I is stabilized by the π-π-stacking and hydrogen bonds interaction.  相似文献   

2.
A novel uranyl complex with dimeric lacunary polyoxoanion like open-mouthed clam, Na5[(A-α-SiW9O33H3)2K{UO2(H2O)}2], was prepared and characterized by elemental analysis, infrared and ultraviolet–visible spectroscopy and single crystal X-ray diffraction. In the anion, two A-α-SiW9O3410− groups share two terminal oxygen atoms Od′ derived from removal of three corner-shared W atoms from saturated α-Keggin anion, forming a dimeric anion with an open mouth in which potassium ion and uranyl ions are coordinated. Uranium atom adopts a pentagonal bipyramidal geometry. The coordinating anions are linked by sodium ions via coordination of terminal or bridging oxygen atoms, forming two-dimensional layer arrangement. Between the layers are the hydrogen bonds from which a supramolecular architecture is created. UV–VIS spectrum gives W–O and U–O charge transfer transitions at 230–265 and 432 nm, showing the change of geometry of the polyanion and weakening of the U–O bonds of the uranyl cation. Electronic supplementary material The online version of this article () contains supplementary material, which is available to authorized users.  相似文献   

3.
The crystal structures of isostructural mixed-ligand fluorosulfate complex compounds of indium(III) M2[InF3(SO4)H2O] (M = K, NH4), formed of K+ cations, NH4 + respectively, and complex [InF3(SO4)H2O]2– anions are determined. In the complex anion, the indium atom surrounded by three F atoms, the oxygen atom of the coordinated H2O molecule, and two oxygen atoms of the bridging sulfate group forms a slightly distorted octahedron (CN 6). Via alternating bridging SO4 groups, the polyhedra of In(III) atoms are arranged in polymer chains. The O–H???F hydrogen bonds organize the chains in a three-dimensional network. The K+ and NH4 + cations are located in the structure framework and additionally strengthen it.  相似文献   

4.
The reaction of 3,6-di-(3-methyl-pyridin-2-yI)-s-tetrazine (DMPTZ, II) with CeIII salt [Ce(NO3)3 · 6H2O] generates a new ligand, N-(3-methyl-pyridin-2-yl)-formimidoyl-(3-methyl-pyridin-2-yl) hydrazone (L), and forms a new complex: a mononuclear complex [Ce(L)(NO3)2 (H2O)3] · NO3 (III). Crystal data for III: space group P-1, with a = 0.7133(4) nm, b = 1.1139(2) nm, c = 1.4572(3) nm, α= 102.13(2)°, β= 99.81(3)°, γ= 91.10(3)°, Z = 2, V = 1113.6(7) nm3, μ = 2.123 mm−1 and F(000) = 630. L acts as a tri-dentate chelating ligand in III. There are 10 coordination sites around Ce3+ of III, which are respectively occupied by seven oxygen atoms (four from two nitrate anions and three from three H2O molecules) and three nitrogen atoms (all from L). The cerium atom and three chelating nitrogen atoms are coplanar. The mechanism of the metal assisted decomposition is discussed briefly.  相似文献   

5.
A method for the synthesis of the silver(I) complex with the closo-decaborate anion and triphenylphosphine [Ag2(Ph3P)2B10H10] n was developed and the structure of this complex was studied. The polymeric chain of the complex is formed with participation of Ag(I) atoms, which coordinate the B10H102− anions through the apical (B(1)–B(2), B(9)–B(10)) and equatorial (B(3)–B(6), B(5)–B(8)) edges, the metalligand bonding occurring through three-center two-electron bonds (MHB). The P atoms of two triphenylphosphine molecules are also incorporated in the inner coordination sphere of the metal: the CN of the silver atom is 4 + 1.  相似文献   

6.
The crystal structure of Na3NpO2(OOCCH3)3ClO4 · H2O was studied by single-crystal X-ray diffraction method. The structure is composed of the complex anions NpO2(OOCCH3)3]2−, perchlorate anions, Na cations, and water molecules. The oxygen environment of Np(V) is a hexagonal bipyramid whose equatorial plane is formed by the oxygen atoms of three acetate ions. In addition to the acetate anions, the structure contains the perchlorate ion whose oxygen atoms, except for one, are included in the coordination environment of Na+ cations.__________Translated from Koordinatsionnaya Khimiya, Vol. 31, No. 8, 2005, pp. 636–640.Original Russian Text Copyright © 2005 by Charushnikova, Fedoseev, Starikova.  相似文献   

7.
The hypothesis that the degree of hydration of poly(oxyethylene) (POE) in aqueous solution depends on the mole ratio of water molecules to ether oxygen atoms in the molecule has been verified by studying the isotropic Raman spectra in the O−H stretching region for four short-chain POEs (C 1E n C 1 withn=1−4). Excellent coincidence of the O−H stretching Raman band for all four POEs studied in the range of mole ratio H2O/O ether from 25 to 0.6 was observed, thus confirming the assumption stated above. A conclusion that all ether oxygen atoms in the POE molecule participate in hydrogen bonding with water molecules has been made.  相似文献   

8.
The coordination compound [Co(DH)2(PP)2][BF4]2 · 2H2O (DH is the dimethylglyoxime residue, PP is nicotinamide) was synthesized and studied by X-ray diffraction. The equatorial plane of the octahedral Co(III) complex contains two DH residues combined by intramolecular hydrogen bonds O-H…O, while the apical positions are occupied by two PP molecules. A method for the optimal use of the complex for enhancement of the biosynthesis of standard and acid-stable amylases of the micromycete Aspergillus niger 33–19 CNMN FD 02A and lipases of the micromycete Rhizopus arrhizus Fischer CNMN FD 03L was depeloped. The introduction of the complex in a concentration of 1–5 mg/l into the culture medium of Aspergillus niger 33-19 CNMN FD 02A reduces the process cycle by 24 h. The stimulating effect of the introduction of the complex (5 mg/l) into the culture medium of the Rhizopus arrhizus Fischer CNMN FD 03L strain is 55.5%.  相似文献   

9.
Considering the structural unit of the rhombohedral BaTiO3 phase in the form of Ti(-O...Ti)6 which was constructed by neutron diffraction data, we revealed an atomic group in the form of a pyramidal complex anion TiO32−. Inspection of the Raman spectra of this phase showed symmetry group C s for this complex anion. From the similarity of the Raman spectra of all ferroelectric BaTiO3 phases, we inferred that the orthorhombic phase and tetragonal phase are also built of TiO32− complex anions. In the paraelectric cubic phase, TiO32− complex anions decompose to oxygen ions O2− and Ti2+(O)2 molecules, which are randomly oriented over 12 possible positions. Average Ti-O distances derived from neutron diffraction data were used to calculate Ti-O and Ti=O bond lengths in TiO32− complex anions of the ferroelectric BaTiO3 phases. Two types of Ti-O...Ti bridges were found to exist; they belong to weak and strong intermolecular bonds, which are similar to weak and strong hydrogen bonds (H-bonds) in ferroelectrics. Weak bonds exist in all of the three ferroelectric phases; strong bonds are only in the orthorhombic phase and the tetragonal phase. As a result of a low potential barrier height in strong bonds, an oxygen atom persistently hops from one potential well to an adjacent one, which is responsible for bands appearing below 100 cm−1 in the Raman spectra of the tetragonal phase and orthorhombic phase. The data obtained on the structure of the ferroelectric BaTiO3 phases were used to interpret their spontaneous polarization, repolarization, and permittivity.  相似文献   

10.
Summary.  Single crystals of MgAl2F8(H2O)2 have been obtained under hydrothermal conditions (250°C, 14 d) from a starting mixture of AlF3 and MgAlF5(H2O)2 in a 5% (w/w) HF solution. The crystal structure has been determined and refined from single crystal data (Fmmm (#69), Z = 4, a = 7.2691(7), b = 7.0954(16), c = 12.452(2) ?, 281 structure factors, 27 parameters, R(F 2 > 2σ (F 2)) = 0.0282, wR(F 2 all) = 0.0885). The obtained crystals were systematically twinned according to (010/100/001) as twinning matrix, reflecting the pseudo-tetragonal metric. The crystal structure is composed of perowskite-type layers built of corner sharing AlF6 octahedra with an overall composition of AlF4 which are connected via common fluorine atoms of [MgF4/2(H2O)2/1] octahedra. Group-subgroup relations of MgAl2F8(H2O)2 to WO3(H2O)0.33 and to other M(II)M(III)2 F8(H2O)2 structures are briefly discussed. Above 570°C, MgAl2F8(H2O)2 decomposes under elimination of water into α-AlF3, β-AlF3, and MgF2. Received October 29, 2001. Accepted (revised) December 6, 2001  相似文献   

11.
Crystals of Ba Na ethylenediaminetetraacetatocobaltate(III) perchlorate, NaBa2[Co(Edta)]2(ClO4)3 · 9H2O, contain two crystallographically nonequivalent Ba2+ cations and two complex cations [Co(Edta)]? (Edta4? is ethylenediaminetetraacetic acid anion), the latter anions showing opposite chirality. The nearest surrounding of the Ba2+ ions involves three water molecules (including two bridging water molecules), six O atoms of four complexes [Co(Edta)]? and the perchlorate O atom. Tetrameric fragments Ba2(H2O)4[Co(Edta)]2(ClO4)2 are united through the Ba-O bonds into layers with the Ba atoms in the middle of the layers and the perchlorate ions and complex anions at the periphery; in the latter anions, noncoordinated O atom of one of the R-metallocycles is directed outside. The Na atom of the Na(H2O)(ClO4) group located between the layers is bonded to these O atoms of the neighboring layers.  相似文献   

12.
The crystal and molecular structure of doubly protonated tetraazamacrocyclic complex of gold(III) [Au(C14H24N4)][H3O](ClO4)4 has been determined. The crystals are monoclinic: a = 11.158(2) Å, b = 8.243(1) Å, c = 14.756(2) Å; β = 98.65(1)°, V = 1341.8(3) Å3, Z = 2, ρ(calc) = 1.134 g/cm3, space group P21/n. The structure is built of almost flat centrosymmetrical Au(C14H24N4)]3+ and [H3O]+ cations and [ClO4]? anions. The gold atom is coordinated with four nitrogen atoms of the ligand forming a flat square. The coordinated ligand is protonated at its γ-carbon atoms of the two six-membered chelate rings. The Au-N bond lengths are almost identical (the mean value is 1.994 Å). The six-membered rings of the complex contain C=N diimine bonds. The [H3O]+ oxonium ion has H-bonds with the oxygen atoms of perchlorate ions.  相似文献   

13.
A new compound of C17H20FN3O32+ · 2HSO4·H2O [ciprofloxacindi-um bis(hydrosulfate) monohydrate], C17H18FN3O3 1-cyclopropyl-6-fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl)-3-quinolinecarboxylic acid (CfH, ciprofloxacin) is obtained and its crystal structure is determined. The crystal contains CfH32+ and HSO4 ions and crystallization water molecules. Hydrogen (H3), which forms an intramolecular hydrogen bond with oxygen O2 of the carboxyl group, is attached to the carbonyl O1 atom. Hydrogen H4 of the carboxyl group is hydrogen bonded to the crystallization water molecule which links CfH32+ with two HSO4 groups by hydrogen bonds. Both H atoms at N3 of the piperazine ring form hydrogen bonds with two oxygen atoms of other HSO4 anions. Intramolecular hydrogen bonds of two types are present in the CfH32+ cation. One of them forms a six-membered ring, bonding O1 and O2 atoms, while the other, also enclosing a six-membered ring, links fluorine and carbon C14 atoms. Original Russian Text Copyright ? 2009 by A. D. Vasiliev, N. N. Golovnev, and I. A. Baidina __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 50, No. 1, pp. 165–168, January–February, 2009.  相似文献   

14.
Three new coordination polymers, [RE(5-Nip)(5-HNip)(H2O)2)] · 2H2O (RE = Y (I), Ho (II), and Er (III)) were synthesized by hydrothermal reactions of lanthanide nitrates with 5-nitroisophthalic acid (H2Nip) and characterized by IR spectra, elemental analysis, and single-crystal X-ray diffraction. X-ray diffraction studies suggest that all the two-dimensional 5-nitroisophthalic complexes crystallize in the P space group and are isomorphic. The two-dimensional layer-like structures are constructed by the lanthanide ions bridged by 5-Nip2− ligands, and the layers further packed into 3D complexes through hydrogen bonds and two kinds of π-π stacking interactions. These complexes exhibit high stabilities up to 465 (1), 518 (2), and 528°C (3), respectively. According to the effective ionic radii of eight-coordinate lanthanide, Y(III) should be arranged before Ho(III) and Er(III), and we obtain a series of lines (except for the RE-OW bonds) in the corresponding RE-O against their ionic radii. In these complexes the yttrium complex could be located before the other two complexes according to the position of its ionic radius, and the ionic radii become a key factor in the formation of these complexes. The text was submitted by the authors in English.  相似文献   

15.
Summary.  Hydrazinium(+2) fluoroarsenate(III) fluoride was prepared by the reaction of hydrazinium(+2) fluoride and liquid arsenic trifluoride. N2H6AsF4F is stable at 273 K, but decomposes slowly at room temperature. N2H6AsF4F crystallizes in the orthorhombic space group Pnn2 with a = 774.0(2) pm, b = 1629.2(4) pm and c = 436.6(1) pm; V = 0.5506(3) nm3, Z = 4 and d c  = 2.461 g cm−3. The structure consists of N2H6 2+ cations, AsF4 anions, and F anions and is interconnected by a hydrogen bonding network. Distorted trigonal-bipyramidal AsF4 units are very weakly interconnected and form chains along the b axis. Bands in the Raman spectrum are assigned to the vibrations of N2H6 +2 cations and AsF4 anions. Corresponding author. E-mail: adolf.jesih@ijs.si Received April 18, 2002; accepted July 15, 2002  相似文献   

16.
The complex [Co(2-Me-Pyz)2(H2O)4](NO3)2 is synthesized and its structure is determined. The crystals are monoclinic: space group P21/n, a = 10.685(2) Å, b = 6.837(1), c = 12.515(3) Å, β = 91.84(3)°, V = 913.8(3) Å3, ρcalcd = 1.042 g/cm 3, Z = 2. The Co2+ ion (in the inversion center) is coordinated at the vertices of the distorted octahedron by two nitrogen atoms of methylpyrazine and four oxygen atoms of the water molecules (Co(1)–N(1) 2.180(3), average Co(1)–O(w) 2.079(3) Å, angles at the Co atom 87.9(1)–92.1(1)°). Supramolecular pseudometallocycles are formed in the structure through the O(w)–H…N(1) hydrogen bonds between the coordinated H2O molecules and the terminal nitrogen atoms of the 2-methylpyrazine molecules. Their interaction results in the formation of supramolecular layers joined by the NO3 groups into a three-dimensional framework.  相似文献   

17.
The U(VI) complex with cyanoacetic acid, [UO2(H2O)2(NCCH2COO)2] (I), was synthesized from an aqueous solution, and its X-ray diffraction analysis was carried out. The crystals are orthorhombic: space group Pca2 1, a = 25.9605(7) Å, b = 6.7634(2) Å, c = 6.3398(2) Å, V = 1113.15(6) Å3 at 100 K, and Z = 4. The coordination polyhedron of the uranium atom is a distorted pentagonal bipyramid. The cations UO 2 2+ are bound into infinite zigzag chains by the bridging carboxyl groups of one of the anions of cyanoacetic acid. The carboxyl oxygen atom of the second anion, which is not involved in coordination, and the nitrogen atoms of the cyano groups form hydrogen bonds with the coordination water molecules. The layer structure of the compound is formed through the hydrogen bonds. The absorption spectra in the visible and infrared ranges of the crystalline compound are measured and analyzed.  相似文献   

18.
The two complexes, [RE(Gly)4(Im)(H2O)](ClO4)3(s)(RE = Eu, Sm), have been synthesized and characterized. The standard molar enthalpies of reaction for the following reactions, RECl3·6H2O(s)+4Gly(s)+Im(s)+3NaClO4(s) = =[RE(Gly)4(Im)(H2O)](ClO4)3(s)+3NaCl(s)+5H2O(l), were determined by solution-reaction colorimetry. The standard molar enthalpies of formation of the two complexes at T = 298.15 K were derived as Δf H mΘ {Eu(Gly)4(Im)(H2O)}(ClO4)3(s)} = = −(3396.6±2.3) kJ mol−1 and Δf H mΘ {Sm(Gly)4(Im)(H2O)}(ClO4)3(s)} = −(3472.7±2.3) kJ mol−1, respectively.  相似文献   

19.
The crystal structure of bis(semicarbazido)copper(II) nitrate [Cu(NH2NHC(O)NH2)2](NO3)2 has been studied by X-ray diffraction. Monoclinic crystals, a = 6.835(2) Å, b = 7.733(2) Å, c = 10.320(3) Å, β = 105.701(3)°, V = 525.1(2) Å3, space group P21/c, Z = 2, d msd = 2.136 g/cm3, μ(MoK α) = 2.143 mm−1. The structure was solved with the program for automatic analysis of Patterson’s function and refined by full-matrix least squares in an anisotropic approximation for all non-hydrogen atoms using 753 independent reflections; R 1 = 0.0203. The square environment of the Cu atom is formed from the amino nitrogen atoms of the hydrazine fragments and the C=O oxygen atoms of the two semicarbazide bidentate molecules (Cu-N 1.928 Å, Cu-O 1.999 Å). The axial positions are occupied by the O atoms of the NO 3 outer-spheric anions (Cu-O 2.505 Å). In the structure, the complex cations and the NO 3 anions are linked into a framework by N-H...O type hydrogen bonds. Original Russian Text Copyright ? 2007 by G. V. Romanenko, Z. A. Savelieva, and S. V. Larionov __________ Translated from Zhurnal Strukturnoi Khimii, Vol. 48, No. 2, pp. 370–373, March–April, 2007.  相似文献   

20.
The structure of the bismuth(III) complex with N-ethylthiourea (Ettu) has been determined for the first time. We found that the crystal structure of [Bi(Ettu)4(ClO4)2]ClO4 is built of distorted octahedral cations [Bi(Ettu–S)4(ClO4)2]ClO4]+ and anions ClO4-. The deviation of one of the two independent Ettu molecules from the plane structure is explained by the mutual repulsion of the ligands and the formation features of hydrogen bonds. The C2H5(Ettu) group is in the cis position relative to the thiocarbonyl group.  相似文献   

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