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1.
Ion selective and complexing properties of 1,5-bis[2-(dioxyphosphoryl-4-methoxy)phenoxy]-3-oxapentane dihydrate H4M2 · 2H2O (I) were described. X-ray diffraction analysis for compound I was performed. The crystals are orthorhombic, a = 7.9818(16) ?, b = 30.553(6) ?, c = 9.0559(17) ?, V = 2208.5(8) ?3, Z = 4, space group Pnma, R = 0.0500 over 1372 reflections with I > 2??(I). In I, the H4M2 molecules are combined by hydrogen bonds (HB) with two crystallographically independent H2O(7) and H2O(8) molecules to give neutral H4M2 · 2H2O aggregates. The HB between the phosphoryl and hydroxyl oxygen atoms of the aggregates and the donor O(7)-H??O(8) HB give rise to a layered structure. Conclusions about the Cu(H2M2) compound structure were drawn based on the X-ray diffraction, DTA, and vibrational spectroscopy data.  相似文献   

2.
《Solid State Sciences》1999,1(6):395-408
Chemical preparation and crystal structure are given for a new cyclohexaphosphate: ((NH3CH2CH2)3N)2P6O18·6H2O. This compound is triclinic P¯1 with the following unit-cell parameters: a = 10,281(1)Å, b = 11.083(1)Å, c = 9.307(2)Å, α = 103.83(1) °, β = 108.56(1) °, γ = 68.11(1) °, Z = 1, V = 924.2(3)Å3 and pcal. = 1.582 g.cm−3. Its atomic arrangements contain layers built by P6O18 ring anions spreading in the plans (001). Between these layers are located the organic groups which form hydrogen bonds with oxygen atoms of P6O18 rings and water molecules. Crystal structure has been solved and refined to R = 0.028 using 4540 independent reflections. The thermal behavior has been investigated and interpreted by comparison with IR absorption spectroscopy and X-ray diffraction experiments.  相似文献   

3.
Using ESR and IR spectroscopy, the structures of >Si(O–C·=O)(CH2–CH3) (1) and >Si(CH2–CH·–CH3)(CH2–CH3) (2) radicals were deciphered. The directions and kinetic parameters of reactions of intramolecular rearrangements in these radicals were determined. The reactions of hydrogen atom abstraction in radical (1) from the CH2 and CH3 groups were studied. It was found that the endothermic reaction of hydrogen atom abstraction from the methyl group occurs at a higher rate than the exothermic reaction with the methylene group. The differences are determined by changes in the size of a cyclic transition state. Based on the experimental data, the strengths of separate C–H bonds in surface fragments are compared. The rearrangement >Si(CH2–CH·–CH3)(CH2–CH3) >Si(C·(CH3)2)(CH2–CH3) was discovered and its mechanism was determined. One of its steps is the skeletal isomerization Si- (2)- . (1)Si- (1)- . (2). Experimental data are analyzed using the results of quantum-chemical calculations of model systems.  相似文献   

4.
The preparation and structural characterization of two trinuclear vanadium complexes, (V(3)(μ(3)-O)O(2))(μ(2)-O(2)P(CH(2)C(6)H(5))(2))(6)(H(2)O), 1, and (V(3)(μ(3)-O)O(2))(μ(2)-O(2)P(CH(2)C(6)H(5))(2))(6)(py), 2, are reported. In these nonclassical structures, the planar central core consists of the three vanadium atoms arranged in the form of an acute quasi-isosceles triangle with the central oxygen atom multiply bonded to the vanadium atom at the center of the vertex angle and weakly interacting with the two other vanadium atoms on the base sites, each of which contain one external multiply bonded oxygen atom. Reacting VO(acac)(2)in the presence of diphenylphosphinic acid affords (VO(O(2)PPh(2))(2))(∞), 3, while 2-hydroxyisophosphindoline-2-oxide at room temperature in CH(2)Cl(2) affords ((H(2)O)VO(O(2)Po-(CH(2))(2)C(6)H(4))(2))(∞), 4, and at 120 °C in EtOH yields (VO(O(2)P(o-(CH(2))(2)(C(6)H(4)))(∞), 5 on the basis of elemental analyses. The thermal and chemical stability of the complexes were assessed by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC) measurements. The bond strengths of the vanadium atoms to the OH(2) ligand in 1 and to the NC(5)H(5) ligand in 2 were assessed at 10.7 and 42.0 kJ/mol respectively. Room temperature magnetic susceptibility measurements reveal magnetic moments for trinuclear 1 and 2 at 3.02(1) and 3.05(1) μ(B/mol), and also close to spin only values (1.73 μ(B)) values for 3, 4, and 5 at 1.77(2), 1.758(7), and 1.77(3) μ(B), respectively. Variable-temperature, solid-state magnetic susceptibility measurements were conducted on complex 2 in the temperature range of 2.0-298 K and at an applied field of 0.5 T. Magnetization measurements at 2 and 4 K confirmed a very weak magnetic interaction between the vanadyl centers.  相似文献   

5.
[Pt3S2(P(CH2OH)3)6](PF6)(OH)·H2O (1) is obtained by a reaction of [Pt3S2(P(CH2OH)3)6]Cl2 with NH4PF6. The crystal structure of 1 was determined by a single crystal X-ray diffraction analysis (space group R{ie638-1}c, a = 12.0042(2) Å, c = 52.6879(11) Å, V = 6575.2(2), Z = 6, C18H57F6O20P7Pt3S2, d x = 2.385 g/cm3, T = 150 K, R 1 = 0.044 for 2123 F 0 > 4δ(F) until 2θmax = 63°). The cations contain a {Pt33-S)2}2+ core with nonbonding Pt…Pt distances of 3.1536(6) Å. The Pt atoms are in a square planar environment; the Pt-S and Pt-P bond lengths are 2.3586(16) Å and 2.260(2) Å respectively.  相似文献   

6.
Crystals of [Cr3O(CH3COO)6(H2O)3][UO2(CH3COO)3]·3H2O (I) were synthesized for the first time and studied by X-ray crystallography. The crystals of I are orthorhombic: a = 8.3561(3) ?, b = 16.8421(5) ?, c = 25.7448(9) ?, V = 3623.2(2) ?3, space group P212121, Z = 4, R = 0.0409. The structure is composed of trinuclear [Cr3O(CH3COO)6(H2O)3]+ complexes and mononuclear [UO2(CH3COO)3]? complexes classified with crystal-chemical groups A3M3B 6 2 M 3 1 (A = Cr3+, M3 = O2?, B2 = CH3COO?, M1 = H2O) and AB 3 01 (A = UO 2 2+ , B01 = CH3COO?), respectively. The complexes are bound to each other by electrostatic interactions and hydrogen bonds involving outer-sphere water molecules. The results of IR spectroscopic study of I are in good agreement with the structural data for the crystal.  相似文献   

7.
The coordination compounds [Cd(CH3COO-κO 1,O 2)2(phenanthroline-kN 1 N 2)(H2O)] · H2O (1) and [Cd{μ-(CH3CH2COO-κO 1,O 2)}2(phenanthroline-κN 1,N 2)]2 · 2CH3CH2COOH (2) were synthesized and characterized by elemental and thermal analysis and IR spectroscopy. Crystal and molecular structures of both compounds were determined. The complexes are air stable and fairly soluble in water. In both compounds the cadmium is seven-coordinate and contains chelating phenanthroline and two chelating carboxylate groups in the inner coordination sphere. The seventh coordinating oxygen belongs to water in 1 and to bridging carboxylate in 2. All carboxylate groups are bonded unsymmetrically to the central atom. The coordination polyhedra can be described as distorted pentagonal bipyramid (compound 1) and distorted capped tetragonal bipyramid (compound 2). In the structure of 1 intermolecular O(water)–H ··· O (water/carboxylate) hydrogen bonds create a two-dimensional net along the crystallographic a0c plane. Each molecule of 2 is connected to two propionic acid molecules via hydrogen bonds. In both compounds exist π-stacking interactions.  相似文献   

8.
The crystals of the title compounds (H3O)(C3H5N2)[Mn(OH)6Mo6O18]·3.5H2O 1 and (H3O)3[Co(OH)6Mo6O18]·7H2O 2 have been prepared and structurally determined by X-ray single-crystal diffraction. Compound 1 crystallizes in monoclinic, space group C2/c with a = 21.5018(9), b = 10.9331(5), c = 11.8667(5)A,β = 95.3570(10)o, V = 2777.5(2)A3, Z = 4, Dc = 2.802 g/cm3, Mr = 1171.80,μ(MoKα) = 3.173 mm-1, F(000) = 223, the final R = 0.0458 and wR = 0.1041 for 2093 observed reflections (I>2σ(I)); Compound 2 crystallizes in monoclinic, space group P21/c with a = 11.4042(12), b = 10.9481(11), c = 11.6722(12)A, β= 99.948(2)o, V = 1435.4(3)A3, Z = 2, Dc = 2.794 g/cm3, Mr = 1207.80,μ(MoKα) = 3.223 mm-1, F(000) = 1160, the final R = 0.0544 and wR = 0.1066 for 1906 observed reflections (I > 2σ(I)). Both compounds 1 and 2 adopt the Anderson structure, in which the anion is of centrosymmetry and formed by six octahedral edge-sharing MoO6 units surrounding the central MO6 (M = Mn or Co) octahedron.  相似文献   

9.
The chemistry of (H(2)O)(n)(?-), CO(2)(?-)(H(2)O)(n), and O(2)(?-)(H(2)O)(n) with small sulfur-containing molecules was studied in the gas phase by Fourier transform ion cyclotron resonance mass spectrometry. With hydrated electrons and hydrated carbon dioxide radical anions, two reactions with relevance for biological radiation damage were observed, cleavage of the disulfide bond of CH(3)SSCH(3) and activation of the thiol group of CH(3)SH. No reactions were observed with CH(3)SCH(3). The hydrated superoxide radical anion, usually viewed as major source of oxidative stress, did not react with any of the compounds. Nanocalorimetry and quantum chemical calculations give a consistent picture of the reaction mechanism. The results indicate that the conversion of e(-) and CO(2)(?-) to O(2)(?-) deactivates highly reactive species and may actually reduce oxidative stress. For reactions of (H(2)O)(n)(?-) with CH(3)SH as well as CO(2)(?-)(H(2)O)(n) with CH(3)SSCH(3), the reaction products in the gas phase are different from those reported in the literature from pulse radiolysis studies. This observation is rationalized with the reduced cage effect in reactions of gas-phase clusters.  相似文献   

10.
The bis(cyclopropylammonium)dihydrogenodiphosphate monohydrate is a new diphosphate associated with the organic molecule C3H5NH2. We report the chemical preparation and the crystal structure of this organic cation diphosphate. (C3H5NH3)2H2P2O7.H2O is orthorhombic (S.G. : P212121), with Z = 4 and the following unit-cell parameters : a = 4.828(1) Å, b = 11.011(1) Å, c = 25.645(2) Å. The P2O7 groups and H2O water molecules form a succession of bidimensional layers perpendicular to the c axis. The organic cations ensure the three-dimensional cohesion by NH-O hydrogen bonds.  相似文献   

11.
Reacting VO(acac)2 with six equivalents of dibenzylphosphinic acid in the presence of 4,4′-bipyridine or μ2-N1,N2-di(pyridin-4-yl)oxalamide leads to trimeric (V3(μ3-O)O2)(μ2-O2P(CH2C6H5)2)6(4,4′-bipyridine) or the hexamer [(V3(μ3-O)O2)(μ2-O2P(CH2C6H5)2)6]2(μ2-N1,N2-di(pyridin-4-yl)oxalamide). The complexes were characterized by spectroscopic (FTIR and 1H NMR spectroscopies), TGA, and by single crystal X-ray diffraction measurements. The structures consist of a planar central core where three vanadium ions are arranged in the form of a quasi-isosceles triangle and contain an interstitial O which is multiply bonded to one V and weakly interacting at different bond distances to the remaining two V ions.  相似文献   

12.
Single crystals of (NH4)2[(UO2)2C2O4(CH3COO)4] · 2H2O have been synthesized and studied. The compound crystallizes in the orthorhombic system with the unit cell parameters a = 6.9225(14) Å, b = 12.327(3) Å, c = 14.619(3) Å, space group Immm, Z = 2, and V = 1247.6(5) Å3. The main structural units of the crystals are the isle binuclear groups [(UO2)2C2O4(CH3COO)4]2? belonging to the crystal-chemical group A2K02B 4 01 (A = UO 2 2+ , K02 = C2O 4 2? , B01 = CH3COO?) of the uranyl complexes. The uranium-containing groups are linked into a three-dimensional framework due to electrostatic interaction with the ammonium cations and through a system of hydrogen bonds involving atoms of the water molecules, oxalate and acetate ions, and ammonium and uranyl cations.  相似文献   

13.
Two new Cd(II) coordination polymers, [Cd(C4H6N2)2(C4H2O4)(H2O)2] n (1) (where C4H6N2?=?2-methylimidazole, C4H2O4?=?fumarate), and [Cd(C4H6N2)(H2O)(C4H4O4)] n ?·?nH2O (2), (where C4H4O4?=?succinates), have been prepared and structurally characterized by single crystal X-ray diffraction. Complex 1 crystallizes in the triclinic space group P 1 in a one-dimensional chain structure, in which carboxy is monodentate; a three-dimensional supermolecular network structure was formed through hydrogen bonding. In complex 2, the coordination geometry of the Cd atoms is a pentagonal bipyramid, and a two-dimensional sheet is formed though carboxyl group bridging. In 1 and 2, IR spectra indicate the presence of bridging carboxyl groups, confirmed by structure analyses.  相似文献   

14.
Iron acetate of composition [Fe3O(CH3COO)6(H2O)3][AuCl4]·6H2O (I) was synthesized and investigated by X-ray diffraction analysis and Mössbauer spectroscopy. The [Fe3O(CH3COO)6(H2O)3]+ complex cation has a structure typical for 3-O bridged trinuclear ferric compounds with iron atoms lying at the vertices of a regular triangle with an oxygen atom at the center. The iron atoms are each coordinated by 4 oxygen atoms of the four bridging carboxylic groups, the 3-O bridging atom, and the coordinated water molecule in the trans-position to the latter. In the trinuclear cation, the Fe(III) ions are coupled by antiferromagnetic exchange interactions with the exchange parameter J = -29.0 cm –1 (HDVV model for D 3h symmetry). The specific role of the solvate water molecules in structure formation is discussed.  相似文献   

15.
用X-射线衍射法测定了[C5H4C(CH3)(C3H7)CH2CH= CH2]NdMg2(μ3-OH)(μ3-Cl)(μ2-Cl)3(THF)4Cl的晶体结构。它属三斜晶系,空间群为P1- ,a= 12.698(3), b= 13.616(3), c= 13.712(3), α= 68.91(3), β= 84.34(3), γ= 63.07(3)°, V= 1966(1)3, Mr= 849.74, Dx= 1.412 g·cm - 3, μ= 1.7297 m m - 1, F(000)= 840, Z= 2, R= 0.073, w R= 0.086(I≥3σ(I))。分子中Nd(Ⅲ)原子的配位数为八,形成一个严重扭曲的八面体结构。两个Mg 原子的配位情况相似,它们的配位数都是六,构成两个扭曲的八面体。这三个八面体通过三个共用平面联接  相似文献   

16.
17.
The reaction of MoO2(acac)2 and dibenzylphosphinic acid in ethanol leads to a red distorted cubic tetrameric cluster, Mo4(??3-O)4(??2-O2P(CH2C6H5)2)4O4, and a pink open mixed-valent cluster, Mo4(??3-O)2(??2-O2P(CH2C6H5)2)6O6, when the reduction is carried out at 120 and 75 °C, respectively. 95Mo NMR spectroscopy revealed a singlet for Mo4(??3-O)4(??2-O2P(CH2C6H5)2)4O4 (1) at 584.9 ppm (????1/2 = 4500 Hz) and two resonances for Mo4(??3-O)2(??2-O2P(CH2C6H5)2)6O6 (2) at 238.8 ppm (????1/2 = 1250 Hz) and 6.4 ppm (????1/2 = 5999 Hz), which were assigned to the Mo(V) and Mo(VI) sites, respectively. DFT geometries and 95Mo DFT-GIAO chemical shifts for Mo4(??3-O)4(??2-O2P(CH3)2)4O4 (3) and Mo4(??3-O)2(??2-O2P(CH3)2)6O6 (4) are consistent with X-ray crystallography and 95Mo NMR of 1 and 2. The open complex, Mo4(??3-O)2(??2-O2P(CH2C6H5)2)6O6·2(CH2Cl2), exhibits a central Mo(V)?CMo(V) single bond at 2.6217(5) Å with each Mo(V) atom bonded to one oxo (trans-disposed) terminal ligand.  相似文献   

18.
Cs3[UO2(CH3COO)3]2[UO2(CH3COO)(NCS)2(H2O)] (I) and Cs5[UO2(CH3COO)3]3[UO2 (NCS)4(H2O)] · 2H2O (II) have been synthesized via the reaction between uranyl acetate and cesium thiocyanate in aqueous solution. According to single-crystal X-ray diffraction data, both compounds crystallize in monoclinic system with the unit cell parameters a = 18.7036(5) Å, b = 16.7787(3) Å, c = 12.9636(3) Å, β = 92.532(1)°, space group C2/c, Z = 4, R = 0.0434 (I); and a = 21.7843(3) Å, b = 24.6436(5) Å, c = 13.1942(2) Å, β = 126.482(1)°, space group Cc, Z = 4, R = 0.0273 (II). Uranium-containing structural units of compound (I) are mononuclear [UO2(CH3COO)3]? and [UO2(CH3COO)(NCS)2(H2O)]? moieties, which correspond to the AB 3 01 and AB01M 3 1 crystallochemical groups (A = UO 2 2+ , B01 = CH3COO?, M1 = NCS? and H2O). The structure of compound II is built of [UO2(CH3COO)3]? and [UO2(NCS)4(H2O)]2? complexes, which belong to the AB 3 01 and AM 5 1 crystallochemical groups, respectively. Uranium-containing complexes in both structures are linked into a framework by hydrogen bonds and electrostatic interactions with cesium cations. The IR spectra of compounds I and II agree well with X-ray diffraction data.  相似文献   

19.
Tetraalkylammonium chlorides peroxosolvates (CH3)4NCl·H2O2 and (C2H5)4NCl·H2O2 were synthesized. The composition of the solvates was proved by chemical analysis; their X-ray patterns, IR spectra, and thermograms were obtained. The solubility of the solvates in water and their stability in aqueous solutions were investigated.  相似文献   

20.
IR and NMR data showed that the ionic complex Pd2(CHCC6H5)2(C5H7O2)3(BF3)2BF4 isolated in the reaction Pd(Acac)2 + PA + 5BF3OEt2 (Acac is C5H7O2, PA is phenylacetylene) is an adduct of two complexes, namely, (Acac)PdBF4 and [(PA)2Pd(C3-Acac · BF3)]+(Acac · BF3) (coordinatively unsaturated). On dissolution in deuteroacetone or deuteromethanol, the [(Acac)PdF2BF2Pd(C3-Acac · BF3)(PA)2]+(Acac · BF3) adduct decomposed to Pd(Acac)2, 2BF3 · L (L = (CD3)2CO, CD3OD) and the [L(PA)2Pd(C3-Acac]+BF4 complex.  相似文献   

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