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1.
Reactions of N-methyliminobis(methylenephosphonic acid), CH(3)N(CH(2)PO(3)H(2))(2) (H(4)L), with divalent metal acetates under different conditions result in metal diphosphonates with different structures. Mn(H(3)L)(2).2H(2)O (complex 1) with a layer structure was prepared by a layering technique. It is triclinic, P1 macro with a = 9.224(3) A, b = 9.780(3) A, c = 10.554(3) A, alpha = 82.009(6) degrees, beta = 74.356(6) degrees, gamma = 89.853(6) degrees, Z = 2. The Mn(II) ion is octahedrally coordinated by six phosphonate oxygen atoms from four ligands, two of them in a bidentate and two in a unidentate fashion. Each MnO(6) octahedron is further linked to four neighboring MnO(6) octahedra through four bridging phosphonate groups, resulting in a two-dimensional metal phosphonate (002) layer. These layers are held together by strong hydrogen bonds between uncoordinated phosphonate oxygen atoms. The zinc complex Zn(3)(HL)(2) (complex 2) was synthesized by hydrothermal reactions (4 days, 438 K, autogenous pressure). It is monoclinic, P2(1)/n with a = 7.7788(9) A, b = 17.025(2) A, c = 13.041(2) A, beta = 94.597(2) degrees, Z = 4. The structure of complex 2 features a 3D network built from ZnO(4) tetrahedra linked together by bridging phosphonate groups. Each zinc cation is tetrahedrally coordinated by four phosphonate oxygen atoms from four ligands, each of which connects with six zinc atoms, resulting in voids of various sizes. Magnetic measurements for the manganese complex shows an antiferromagnetic interaction at low temperature. The effect of the extent of deprotonation of phosphonic acids on the type of complex formed is discussed.  相似文献   

2.
The layered double hydroxides (LDHs) are nano-ordered layered compounds and well known for their ability to intercalate anionic compounds. Most LDH is prepared conventionally only with divalent and trivalent cations. In this study, Co-Zr-Si LDH, consisting of divalent, tetravalent, and tetravalent cations, was prepared and reacted with monocarboxylic acids at room temperature. The Co-Zr-Si LDH and intercalated compounds have been characterized by energy-dispersive X-ray spectrometry, X-ray powder diffraction, IR spectra, thermal analysis, and scanning electron microscopy (SEM). The insertion of cyanate and carbonate anions into LDH was confirmed by IR spectra. XRD patterns of the prepared Co-Zr-Si LDH showed that the interlayer spacing of the LDH is 0.78 nm. The spacing is similar to that of usual LDH in which chloride, carbonate, or bromide anion is the guest. SEM images showed that Co-Zr-Si LDH can exist as plate-like or fibrous structures.  相似文献   

3.
Hydrothermal reactions of 5-sulfoisophthalic acid (HO(3)SC(6)H(3)-1,3-(CO(2)H)(2), H(3)L) with M(II) carbonate (or oxide) and 4,4'-bipyridine (4,4'-bipy) (or 2,2'-bipyridine, 2,2'-bipy) resulted in three new metal carboxylate-sulfonate hybrids, namely, [CdL(H-4,4'-bipy)] (1) and [Cd(3)L(2)(2,2-bipy)(4)(H(2)O)(2)].2H(2)O (2) with layered structures and [ZnL(H-4,4'-bipy)(H(2)O)].2H(2)O (3), whose structure features a one-dimensional double chain. The cadmium(II) ion in complex 1 is seven-coordinated by five carboxylate oxygen atoms and one sulfonate oxygen atom from four ligands and a unidentate 4,4'-bipyridine. The interconnection of the cadmium(II) ions through bridging carboxylate-sulfonate ligands resulted in the formation of a <002> double layer with the bipyridyl rings orientated toward the interlayer space. Complex 2 has a different layered structure. Cd(1) is seven-coordinated by two bidentate chelating carboxylate groups from two ligands, a bidentate chelating 2,2'-bipy and an aqua ligand, and Cd(2) is octahedrally coordinated by two bidentate chelating 2,2'-bipy's, a sulfonate oxygen, and an aqua ligand. The coordination geometry around Cd(3) is similar to that of Cd(1) with the aqua ligand being replaced by an oxygen atom from the sulfonate group. The carboxylate-sulfonate ligand acts as pentadentate ligand, bridging with three cadmium(II) ions. The bridging of cadmium(II) ions through the carboxylate-sulfonate ligands resulted in the formation of <006> and <003> layers; the 2,2'-bipy molecules and [Cd(2)(2,2'-bipy)(2)(H(2)O)] cations are orientated to the interlayer space. Complex 3 features a 1D metal carboxylate-sulfonate double chain along the diagonal of the a- and b-axes. The zinc(II) ion is octahedrally coordinated by four carboxylate O atoms from three ligands, a unidentate 4,4'-bipy, and an aqua ligand. Each pair of zinc(II) ions is bridged by two carboxylate groups from two ligands to form a dimer, and such dimeric units are interconnected by bridging ligands to form a double chain. The sulfonate group of the carboxylate sulfonate ligand remains noncoordinated and forms a number of hydrogen bonds with aqua ligands as well as lattice water molecules.  相似文献   

4.
A new monomer, 1,2,2,6,6-pentamethyl-4-piperidinyl m-isopropenyl-α, α-dimethylbenzyl carbamate, was synthesized by direct addition of 1,2,2,6,6-pentamethyl-4-piperidinol to m-isopropenyl-α, α-dimethylbenzyl isocyanate in the presence of dibutyltin dilaurate catalyst at elevated temperatures. It was characterized by FT-IR, 1H-NMR. MS, and elemental analysis. It is a potential hindered amine light stabilizer as it contains the 2,2,6,6-tetraalkylpiperidine moiety and its vinylic functionality makes it polymerizable.  相似文献   

5.
Two isotypes of a new layered aluminophosphate, further denoted MDAP-3 and MDAE-1, have been synthesized under hydrothermal conditions using N-methyl-1,3-propanediamine and N-methyl-ethylenediamine, respectively. MDAP-3, with the empirical formula [Al2(HPO4)(PO4)2](C4N2H14)(H2O), crystallizes in the orthorhombic space group Pna2(1) (No. 33) with , , , Z=4, R1=0.0498 and wR2=0.1217. The second solid, MDAE-1, with the empirical formula [Al2(HPO4)(PO4)2](C3N2H12)(H2O), crystallizes in the same space group with , , , Z=4, R1=0.0407 and wR2=0.0954. The two compounds possess the same layer topology. Inorganic layers contain PO3=O, PO3OH, AlO4 and AlO6 polyhedra, linked together to generate a new 4×8 net. MDAP-3 and MDAE-1 represent the first examples of two-dimensional layered aluminophosphates with the Al2P3O12 stoichiometry, and containing AlO6 octahedra.  相似文献   

6.
The zirconium phosphate [Zr(HPO4)(PO4)F2] · 1.5H2en was prepared, and its structure was determined by X-ray diffraction analysis.Translated fromIzyestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 1897–1901, November, 1994.The work was carried out with financial support from SERC (UK) and the National Foundation of Natural Sciences (China).  相似文献   

7.
A new layered indium selenium oxychloride material, InSeO3Cl has been synthesized by a standard solid-state reaction using In2O3, InCl3, and SeO2 as reagents. Single-crystal X-ray diffraction was used to determine the structure of the reported material. InSeO3Cl crystallizes in the orthorhombic space group Pbca (No. 61), with a = 7.0580(14) Å, b = 7.0390(14) Å, c = 16.206(3) Å, V = 805.1(3) Å3, and Z = 8. InSeO3Cl has a layered structure consisting of distorted InO4Cl2 octahedra and SeO3 polyhedra. The Se4+ cations are in asymmetric coordination environment attributed to their stereoactive lone pairs. The lone pairs on the Se4+ cations approximately point in the [101], [?10-1], [10-1], and [?101] direction. A separation of the halophile and the chalcophile moieties is observed from the reported material. Detailed structural analysis with full characterization including infrared spectroscopy, bond valence calculations, thermogravimetric analysis, elemental analysis, and dipole moment calculations are reported.  相似文献   

8.
A new polyoxometalate anion-pillared layered double hydroxide (LDH) was prepared by aqueous ion exchange of a Mg-Al LDH precursor in nitrate form with the tungstocobaltate anions [CoW12O40]5−. The physicochemical properties of the product were characterized by the methods of powder X-ray diffraction, elemental analysis, infrared spectroscopy, thermogravimetric analysis and cyclic voltammetry. It was confirmed that [CoW12O40]5− was intercalated between the brucite-type layers of the LDHs without a change in the structure. Magnetic measurement shows the occurrence of antiferromagnetic interactions between the magnetic centers. The investigation of catalytic performance for this sample exhibits high activity for the oxidation of benzaldehyde by hydrogen peroxide.  相似文献   

9.
A new lead borate, Pb[B8O11(OH)4], has been hydrothermally synthesized and structurally characterized by single crystal X-ray diffraction, FTIR, powder X-ray diffraction and thermogravimetric analysis. The compound crystallizes in the monoclinic system, space group P21/n (No. 14), , , , β=90.327(2)°, , and Z=4. The structure consists of layers of 9-membered borate rings enclosing Pb2+ cations. Adjacent borate layers are interconnected via ionic Pb-O bonds and hydrogen bonding to form a 3D supramolecular network.  相似文献   

10.
A monomeric hydroxide of gallium, LGa(Me)OH, containing terminal hydroxide and methyl groups was prepared by the hydrolysis of LGa(Me)Cl in the presence of N-heterocyclic carbene and water [L = HC{(CMe)(2,6-i-Pr2C6H3N)}2] in high yield and in a pure form. LGa(Me)OH was used as a synthon to assemble the first hetero-bimetallic compound with a Ga-O-Zr core, [(LGaMe)(Cp2ZrMe)](mu-O).  相似文献   

11.
The synthesis, characterization and ethylene polymerization behavior of a set of TpMCl3 complexes (4, M=Ti, Tp=HB(3-neopentyl-pyrazolyl)3(TpNp); 5, M=Ti, Tp=HB(3-tert-butyl-pyrazolyl)3(TptBu); 6, M = Ti, Tp=HB(3-phenyl-pyrazolyl)3(TpPh); 7, M=Zr, Tp=HB(3-phenyl-pyrazolyl)3(TpPh); 8, M=Zr, Tp = HB(3-tert-butyl-pyrazolyl)3(TptBu)) is described. Treatment of these tris(pyrazolyl)borate Group IV compounds with methylalumoxane (MAO) generates active catalysts for ethylene polymerization. For the polymerization reactions performed in toluene at 60 °C and 3 atm of ethylene pressure, the activities varied between 1.3 and 5.1 × 103 g of PE/mol[M] · h. The highest activity is reached using more sterically open catalyst precursor 4. The viscosity-average molecular weights () of the PE’s produced with these catalyst precursors varying from 3.57 to 20.23 × 105 g mol−1 with melting temperatures in the range of 127-134 °C. Further polymerization studies employing 7 varying Al/Zr molar ratio and temperature of polymerization showed that the activity as well as the polymer properties are dependent on these parameters. In that case, higher activity was attained at 60 °C. The viscosity-average molecular weights of the polyethylene’s decreases with increasing Al/Zr molar ratio.  相似文献   

12.
Zirconium titanate (ZT) precursor fibers were prepared via sol–gel technique by dry-spinning method using polyacetylacetonatozirconium (PAZ) and tetrabutyl titanate (TBOT) as starting materials. PAZ and TBOT were added into methanol with vigorous stirring at room temperature for 2 h and mixed together homogenously. The mixture came into being a new and complicated polymerization system, and PAZ and TBOT were connected through –O– bridge forming the –O–Zr–O–Ti–O– linear chains. The evolutions from the precursor fibers to polycrystalline oxide fibers were characterized by Fourier transform infrared (FT–IR) and thermal gravimetry/differential thermal analysis (TG/DTA). The surface of the ZT fibers was smooth, dense in cross-section without cracks by scanning electronic spectroscopy (SEM) and energy dispersive X-ray spectrometry (EDS). The size of the nanocrystals was less than 50 nm and arranged compactly by atomic force microscopy (AFM). The fibriform was still kept and the size of the grains was up to 400–500 nm due to the grain growth with increasing temperature and the ZT fibers were with good high temperature performance.  相似文献   

13.
不同金属离子层状双氢氧化物制备及表征   总被引:4,自引:0,他引:4  
本文采用恒定pH值共沉淀法制备六种层板金属离子不同的层状双氢氧化物(LDH).通过傅立叶变换红外光谱仪(FT-IR)、X-射线衍射仪(XRD)和扫描电子显微镜(SEM)对LDH进行了表征,并利用热重分析(TG)研究了LDH的热分解行为.研究表明,不同金属离子对LDH的层间距、晶粒尺寸等参数有一定影响,团聚程度也有较大的差异.  相似文献   

14.
Reactions of lead(II) acetate with m-aminobenzenesulfonic acid (HL1) and 5-sulfoisophthalic acid (H3L2) afforded two new lead(II) sulfonates, Pb(L1)21 and Pb2(L2)(μ3-OH)(H2O) 2. In compound 1, the lead(II) ion is eight-coordinated by two sulfonate groups bidentately, two sulfonate groups unidentately and two amino groups from six ligands. Each L1 ligand is tetradentate and bridges with three Pb(II) ions. The interconnection of the Pb(II) ions via bridging sulfonate ligands resulted in 〈100〉 and 〈200〉 layers. In compound 2, one Pb(II) ion is six-coordinated by a carboxylate group bidentately, by two carboxylate groups unidentately, by a sulfonate oxygen atom and by an OH anion, whereas the other one is six-coordinated by a bidentate chelating carboxylate group, two μ3-OH anions, a sulfonate oxygen atom and an aqua ligand. The interconnection of irregular PbO6 polyhedra via carboxylate-sulfonate ligands resulted in the formation of a pillared layered structure with the 2D layer being formed; the lead(II) ions, hydroxyl groups, carboxylate and sulfonate groups and the benzene ring as the pillar agent.  相似文献   

15.
Du Y  O'Hare D 《Inorganic chemistry》2008,47(8):3234-3242
New layered pink cobalt hydroxyisocyanates have been prepared by controlled hydrolysis of aqueous solutions of CoCl2.6H2O. Co(OH)(1.4)(NCO) 0.6.0.6H 2O ( 1) is formed when urea is used as the hydrolysis agent and mannitol as the stabilizer, while Co(OH)(1.25)(NCO)(0.75).0.2H2O ( 2) is formed when the hydrolysis agent is changed to hexamethylenetetramine and NaOCN is added to the solution. IR spectroscopy of 1 and 2 indicates that the OCN (-) is N-bonded to Co (2+). The X-ray powder data for 1 could be indexed using an intergrowth model consisting of both rhombohedral ( R3 m (166); a = 3.2031(1) A, c = 23.6876(11) A, hydrotalcite-like, 3 R 1) and hexagonal ( P 63/ mmc (194); a = 3.2005(2) A, c = 15.8303(5) A, Manasseite-like, 2H1) polytypes. Rietveld refinement of the X-ray powder data was performed using a two polytype model and 30% random substitution of the OH (-) ions by OCN (-). Although it is less crystalline, the XRD data for 2 can be indexed using a rhombohedral-symmetry cell with unit cell parameters, a = 3.158 A and c = 21.57 A. Both 1 and 2 exhibit magnetically ordered ground states with a saturation magnetization of ca. 2.0 mu B. The magnetization data is consistent with 3D ferromagnetic ordering of edge-share octahedral-Co (2+) layers with effective spin S' = 1/2.  相似文献   

16.
二维层状磷钒多金属氧酸盐的水热合成及晶体结构   总被引:3,自引:2,他引:3  
利用中温水热技术合成了新型的磷矾铁酸盐(NH3CH2CH2NH3)4[FeV8O12(HPO4)6(PO4)2(H2O)2]·5H2O,通过元素分析、IR光谱、热重分析和X射线衍射确定了晶体结构.该晶体属单斜晶系,P21/n空间群,晶胞参数:a=1.4304(3)nm,b=1.0145(2)nm,c=1.8356(4)nm,β=90.15(3)°,V=2.6637(9)nm3,Z=2,最终偏差因子R1=0.0631,wR2=0.1874.  相似文献   

17.
ZrCl4 reacts with the potassium salt of the bifunctional tridentate Schiff base HOC6H4C(H)=NCH2CH(Me)OH (LH2) in a 1:1 molar ratio in benzene to give a new complex Zr(L)Cl2 which, on reaction with different potassium isopropoxymetallates [e.g., KAl(OPr i )4, KTi(OPr i )5, and KNb(OPr i )6], yield novel heterobimetallic derivatives. These new homo and heteronuclear coordination compounds have been characterized by elemental (N, Cl, Al, Ti, and Nb) analyses, molecular weight (ebullioscopic) measurements and spectral [i.r., n.m.r. (1H, 13C and 27Al)] studies and probable structures for them have been suggested.  相似文献   

18.
Layered zirconium benzylamino-N,N-dimethylphosphonate phosphate (ZBMPA) was prepared by the reaction of zirconyl chloride with benzylamino-N,N-dimethylphosphonic acid (H2BMPA) and phosphoric acid in the presence of hydrofluoric acid. The intercalation of n-alkylamines (n-butylamine, n-heptylamine and n-decylamine) into ZBMPA was primarily investigated at room temperature. These materials were characterized by elemental analysis, ICP, XRD, SEM, FT-IR, Raman spectra, TG and DSC. The composition of ZBMPA is Zr(HPO4)(C6H5CH2N(CH2PO3)2)0.5 · 2.0H2O. The interlayer distance of ZBMPA, n-butylamine, n-heptylamine and n-decylamine intercalation compounds is 2.03, 2.58, 2.52 and 3.17 nm, respectively. ZBMPA and the n-alkylamine intercalation compounds are different in the morphology and vibration spectra. Thermogravimetries of all materials obtained reveal three step mass losses at temperatures of up to 1000 °C. These results indicate that n-alkylamines are intercalated into the galleries of host ZBMPA.  相似文献   

19.
20.
Journal of Solid State Electrochemistry - The composite of polythiophene/sulfur/Ketjen black with the layered spherical structure was designed and prepared to reduce the loss of active material and...  相似文献   

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