Zn3(OH)2V2O7·2H2O纳米片的水热制备

采用硝酸锌、五氧化二钒和氢氧化钠作为反应物,通过一个简单的CTAB辅助的水热方法制备了Zn3(OH)2V2O7·2H2O纳米片.运用XRD,ICP-AES,FTIR,HRTEM,EDS,FE-SEM对产物的晶相和形貌进行了表征.结果表明CTAB在控制产物的形貌、尺寸分布和自组装过程中起着关键作用.同时我们研究了产物的晶体生长行为和自组装过程.     

Synthesis,crystal structure,and catalytic performance of two 3-D supramolecular compounds: (C7N2H7)3(C7N2H6) · PMo12O40 · 2H2O and (C7N2H7)3(C7N2H6)2 · AsMo12O40 · 3H2O

Two organic–inorganic compounds based on Keggin building blocks have been synthesized by hydrothermal methods, (C₇N₂H₇)₃(C₇N₂H₆)?·?PMo₁₂O_40?·?2H₂O (1) and (C₇N₂H₇)₃(C₇N₂H₆)_2?·?AsMo₁₂O_40?·?3H₂O (2) (C₇N₂H₆?=?benzimidazole). Single-crystal X-ray analysis revealed that 1 crystallized in the triclinic system, P-1 space group with a?=?9.8980(4)?Å, b?=?11.2893(4)?Å, c?=?25.8933(9)?Å, α?=?93.307(2)°, β?=?90.630(2)°, γ?=?108.330(2)°, V?=?2740.68(18)?ų, Z?=?2, R ₁(F)?=?0.0740, ωR ₂(F ²)?=?0.1511, and S?=?1.037; 2 crystallized in the triclinic system, P-1 space group with a?=?12.3353(4)?Å, b?=?13.2649(4)?Å, c?=?20.2878(6)?Å, α?=?95.6630(10)°, β?=?100.1720(10)°, γ?=?99.3940(10)°, V?=?3195.72(17)?ų, Z?=?2, R ₁(F)?= 0.0329, ωR₂ (F ²)?=?0.1236, and S?=?1.088. The two compounds show a layer framework constructed from Keggin-polyoxoanion clusters and benzimidazole via hydrogen bonds and π–π stacking interactions, resulting in a 3-D supramolecular network. Both have high catalytic activity for oxidation of methanol. When the initial concentration of the methanol is 5.37?g?m^?3 in air and the flow velocity is 4.51?mL?min^?1, methanol is completely eliminated at 150°C for 1 (160°C for 2).     

Syntheses,Crystal Structures and Properties of Three New Complexes [Ni（C9N2O2H7）2（CH3OH）2],[Zn（C9N2O2H7）2（H2O）2] and [Cd（C9N2O2H7）2（CH3OH）2]

Three novel metal-organic complexes with formulas [Ni(C9N2O2H7)2(CH3OH)2](1),[Zn(C9N2O2H7)2(H2O)2](2) and [Cd(C9N2O2H7)2(CH3OH)2](3) were synthesized by the reactions of Ni,Zn and Cd salts with ethyl 2-benzimidazolylacetate under hydrothermal conditions or layering technique,and characterized by single-crystal X-ray diffraction analysis,IR spec-troscopy,solid-state luminescent properties and thermogravimetric(TG) analysis.The crystal data for these three complexes are as follows:for 1,monoclinic,space group P21/c,a = 9.384(3),b = 9.634(3),c = 11.292(3) ,β = 95.787(5)°,V = 1015.7(5) 3,Z = 2,F(000) = 492,Dc = 1.547 Kg/m3,μ = 1.002 mm-1,the final R = 0.0451 and wR = 0.0900 for 1833 observed reflections with Ⅰ 2σ(Ⅰ);for 2,orthorhombic,space group Pbca,a = 10.031(4),b = 10.379(4),c = 17.525(7),V = 1824.6(12) 3,Z = 4,F(000) = 928,Dc = 1.645 Kg/m3,μ = 1.392 mm-1,the final R = 0.0452 and wR = 0.0996 for 1661 observed reflections with Ⅰ 2σ(Ⅰ);for 3,monoclinic,space group P21/c,a = 9.9114(13),b =10.4852(15),c = 10.4120(14) ,β = 108.453(5)°,V = 1026.4(2) 3,Z = 2,F(000) = 532,Dc = 1.705 Kg/m3,μ = 1.110 mm-1,the final R = 0.0322 and wR = 0.0805 for 1822 observed reflections with Ⅰ 2σ(Ⅰ).In the three complexes,the ethyl 2-benzimidazolylacetate shows the same chelating mode,and the adjacent units are interlinked into a two-dimensional layer through hydrogen-bonds(O-H···O,N-H···O).     

配合物3AgNO3·2[C3H7S(CH2)2SC3H7]的晶体结构

本文测定了配合物3AgNO3·2BPrTE的晶体结构, 该晶体属三斜晶系, 空间各为PI,晶胞参数: a=0.8945(1), b=1.2355(2), c=1.3572(5)nm; α=98.69(2)°, β=92.74(2)°, γ=90.45(1)°; V=1.480nm^3; Z=2, 分子中三个Ag原子的配位数均为5, 但它们的配位多面体各不相同, Ag(3)为四方锥体, Ag(2)为三角双锥, Ag(1)则介于两者之间, NO3^-以单齿、不等长双齿和等长双齿两种形式配位于Ag原子。配体BPrTE也具有两种构象, 反式构象具有C1对称性, 并以两种形式和Ag原子配位, 偏转式构象不具有C4对称性, 与Ag原子形成五元螯合环, 分子为三维无限长链结构。     

Structure of (C3H5NH3)2H2P2O7·H2O

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.     

OH+C2H2与OH+C2H4加成反应的热力学和动力学

OH基与乙炔(乙烯)的反应是控制大气中OH基浓度的重要化学反应。对反应OH+C_2H_2,1975年Davis等用FP-RF技术测定了反应的速率常数。1977年,Perry又用同样方法对该反应作出了研究;结果表明,此反应的速率常数强烈地依赖于压力,与Davis等人的实验结果不符。对反应OH+C_2H_4,Atkinson等人的实验研究表明,压力在30.0kPa以下,反应的速率常数随压力而改变;而在30.0—88.4 kPa之间,与压力无关.这与前人的结果不同。两个反应的产物也因温度不同而异.此外,上述反应一般是在近101kPa下发生的,而实验结果大多是在低压下获得的。且目前尚无直接的理论计算结果。为此,我们在从头算水平上用统计热力学方法,对反应     

Calculated energy barriers for the identity SN2 reaction H2O + CH3OH2+ → +H2OCH3 + OH2 in the gas phase,in water clusters,and in aqueous solution

The bimolecular nucleophilic substitution reaction H₂O + CH₃OH₂⁺ → ⁺H₂OCH₃ + OH₂ has been studied using various quantum chemical methods. Accurate barriers for the reaction in the gas phase are presented and discussed. The effect of microsolvation by water molecules in small clusters has been investigated. Extrapolation of the barrier obtained in the small clusters, using a linear relationship between the activation energy and the proton affinity of water clusters, gives a barrier for the reaction in aqueous solution which is in good agreement with that obtained in separate model calculations (polarized continuum model of a super molecule with the first solvation shell included).     

A novel Anderson-type polyoxometalate: hydrothermal synthesis,crystal structure,and catalytic performance of (H3O)[(3-C5H7N2)2(Cr(OH)6Mo6O18)] · 3H2O

A new Anderson polyoxometalate (H₃O)[(3-C₅H₇N₂)₂(Cr(OH)₆Mo₆O₁₈)]?·?3H₂O (3-C₅H₆N₂?=?3-aminopyridine) was hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction. Crystal data: triclinic, P 1, a?=?7.8482(8)?Å, b?=?10.1800(10)?Å, c?=?10.4103(10)?Å, α?=?88.031(3)°, β?=?78.308(2)°, γ?=?88.842(3)°, V?=?813.91?ų, Z?=?1, R(F)?=?0.0397, wR _ref(F ²)?=?0.1022, and S?=?1.076. The X-ray crystallographic study showed that the structure contains Anderson-type [Cr(OH)₆Mo₆O₁₈]^3? polyoxoanions. The title compound has high catalytic activity for the oxidation of acetone tested in a continuous-flow fixed-bed micro-reactor. When the initial concentration is 18.3?g?m^?3 in air and the flow velocity is 8.5?mL?min^?1, the acetone is completely eliminated at 160°C.     

Complexes H2CO:PXH2 and HCO2H : PXH2 for X=NC,F, Cl,CN, OH,CCH, CH3, and H: Pnicogen Bonds and Hydrogen Bonds

Ab initio MP2/aug’-cc-pVTZ calculations have been carried out to investigate H₂CO : PXH₂ pnicogen-bonded complexes and HCO₂H : PXH₂ complexes that are stabilized by pnicogen bonds and hydrogen bonds, with X=NC, F, Cl, CN, OH, CCH, CH₃, and H. The binding energies of these complexes exhibit a second-order dependence on the O−P distance. DFT-SAPT binding energies correlate linearly with MP2 binding energies. The HCO₂H : PXH₂ complexes are stabilized by both a pnicogen bond and a hydrogen bond, resulting in greater binding energies for the HCO₂H : PXH₂ complexes compared to H₂CO : PXH₂. Neither the O−P distance across the pnicogen bond nor the O−P distance across the hydrogen bond correlates with the binding energies of these complexes. The nonlinearity of the hydrogen bonds suggests that they are relatively weak bonds, except for complexes in which the substituent X is either CH₃ or H. The pnicogen bond is the more important stabilizing interaction in the HCO₂H : PXH₂ complexes except when the substituent X is a more electropositive group. EOM-CCSD spin-spin coupling constants ^1pJ(O−P) across pnicogen bonds in H₂CO:PXH₂ and HCO₂H : PXH₂ complexes increase as the O−P distance decreases, and exhibit a second order dependence on that distance. There is no correlation between ^2hJ(O−P) and the O−P distance across the hydrogen bond in the HCO₂H : PXH₂ complexes. ^2hJ(O−P) coupling constants for complexes with X=CH₃ and H have much greater absolute values than anticipated from their O−P distances.     

Study of the solubility of components in the system Mg(ClO3)2-2NH2C2H4OH · H3C6H5O7-H2O

The solubility of components in the system Mg(ClO₃)₂-2NH₂C₂H₄OH · H₃C₆H₅O₇-H₂O was studied from the complete freezing temperature ?59.4°C to 20.0°C. A polythermal solubility diagram was constructed, in which the crystallization fields were determined for ice, Mg(ClO₃)₂ · 16H₂O, Mg(ClO₃)₂ · 12H₂O, Mg(ClO₃)₂ · 6H₂O, 2NH₂C₂H₄OH · H₃C₆H₅O₇ · H₂O, 2NH₂C₂H₄OH · H₃C₆H₅O₇, and two new compounds, [(HOC(CH₂COOH)₂COO)₂Mg · 2H₂O] and [HOC(CH₂COO)₂MgCOOH · 2H₂O], which were identified by chemical and physicochemical analysis methods.     

Structures, energies, bonding, and NMR properties of pnicogen complexes H2XP:NXH2 (X ═ H, CH3, NH2, OH, F, Cl)

Ab initio calculations have been carried out in a systematic investigation of P···N pnicogen complexes H(2)XP:NXH(2) for X ═ H, CH(3), NH(2), OH, F, and Cl, as well as selected complexes with different substituents X bonded to P and N. Binding energies for complexes H(2)XP:NXH(2) range from 8 to 27 kJ mol(-1) and increase to 39 kJ mol(-1) for H(2)FP:N(CH(3))H(2). Equilibrium structures have a nearly linear A-P-N arrangement, with A being the atom directly bonded to P. Binding energies correlate with intermolecular N-P distances as well as with bonding parameters obtained from AIM and SAPT analyses. Complexation increases (31)P chemical shieldings in complexes with binding energies greater than 19 kJ mol(-1). One-bond spin-spin coupling constants (1p)J(N-P) across the pnicogen interaction exhibit a quadratic dependence on the N-P distance for complexes H(2)XP:NXH(2), similar to the dependence of (2h)J(X-Y) on the X-Y distance for complexes with X-H···Y hydrogen bonds. However, when the mixed complexes H(2)XP:NX'H(2) are included, the curvature of the trendline changes and the good correlation between (1p)J(N-P) and the N-P distance is lost.     

超临界CO2+CH3OH及C2H5OH二元系的气液平衡

在带有石英可视窗和内搅拌的可变体积高压釜内，测定了超临界CO2＋CH3OH及C2H5OH两个系统的相平衡数据，温度为50－200℃，压力4．0－16．0MPa，利用从硬球模型得出的适用于高压高温的状态方程，计算了这两个系统的临界曲线，并与实验值进行比较。     

Tin(IV) complexes with 2-hydroxybenz-(2-hydroxynaphth)aldehyde picolinoylhydrazones (H2Ps, H2Pnf). Crystal structure of [SnCl3(Ps · H)] · CH3OH and [SnCl3(Pnf · H)] · CH3OH

The reactions of SnCl₄ with picolinoylhydrazones of 2-hydroxybenz-(2-hydroxynaphth)aldehydes (H₂Ps, H₂Pnf) in CH₃OH gave non-electrolyte complexes [SnCl₃(Ps · H)] · CH₃OH (I) and [SnCl₃(Pnf · H)] · CH₃OH (II). The imide form of the ligand coordinated to Sn(IV) through the azomethine nitrogen atom and oxyazine and oxy oxygen atoms was proved by UV/Vis, IR, and ¹H NMR spectroscopy. The negative charge on the coordination unit thus arising is counterbalanced by the positive charge caused by the protonation of ligands at the pyridine nitrogen atom of the heterocycle. It was shown that dehydrochlorination of the complexes affords tin-containing species, which correlates with the presence of the corresponding peaks [SnCl₂(Ps)]⁺ and [SnCl₂(Pnf)]⁺ in their mass spectra. The molecular and crystal structures of complexes I and II were determined by X-ray diffraction.     

A Facile Synthesis of 2, 7-Diaminothieno[2, 3-d：5,4-d]-dipyrimidine-4, 5（3H, 6H）diones

2, 7-Diaminothieno[2, 3-d：5, 4-d]dipyrimidine-4, 5（3H, 6H）diones 4 were synthesized by a facile synthetic method, which includes bis-aza-Wittig reaction of bis-iminophosphorane 1 with aromatic isocyanate to give bis-carbodiimide 2 and subsequent reaction of 2 with various dialkylamine in the presence of solid K2CO3 or EtONa.     

Iodination of B12H11OC(O)CH2–3, B12H11OH2–, and B12H11SCN2–

Reactions of iodination of monosubstituted derivatives of B₁₂H₁₁X^2–anion (X = OC(O)CH₃, OH, SCN) were studied. The reactions were shown to proceed smoothly to give B₁₂H₁₀(OC(O)CH₃)I^2–((carboxy)(iodo)[decahydro[I _h1551-²⁰-closo]dodecaborate(2–)] anion), B₁₂H₁₀(OH)I^2–((hydroxo)(iodo)[decahydro[I _h1551-²⁰-closo]dodecaborate(2–)] anion), and B₁₂H₁₀(SCN)I^2–((thiocyanato)(iodo)[decahydro[I _h1551-²⁰-closo]dodecaborate(2–)] anion) in high yields, irrespective of the solvent used (benzene, H₂O–ROH, where R = C₂H₅, CH₂CH₂CH₃).¹     

Synthesis, crystal structure, and IR spectral study of Na[(UO2)(C3H7COO)3] · 0.25H2O and K[(UO2)(C3H7COO)3]

Synthesis, IR spectral study and X-ray diffraction analysis of single crystals of Na[(UO₂)(C₃H₇COO)₃] · 0.25H₂O (I) and K[(UO₂)(C₃H₇COO)₃] (II) were carried out. Compound I is monoclinic, unit cell parameters are: a = 13.5671(15) ?, b = 20.070(2) ?, c = 13.6139(15) ?, ?? = 106.839(2)°, space group P2₁, Z = 8, R = 0.0493. Compound II is orthorhombic, unit cell parameters are: a = 17.1325(9) ?, b = 19.6966(11) ?, c = 21.9686(11) ?, space group P2₁2₁2₁, Z = 16, R = 0.0563. Mononuclear groups [UO₂(C₃H₇COO)₃]^? related to the A ₃ ⁰¹ crystal-chemical group (A = UO ₂ ²⁺ , B ⁰¹ = C₃H₇COO^?) of uranyl complexes are the uranium-containing structural units of crystals I and II. The data of IR spectral study agree well with X-ray diffraction data.     

Syntheses and Crystal Structures of (H3O)(C3H5N2)[Mn(OH)6 Mo6O18]·3.5H2O and (H3O)3[Co(OH)6Mo6O18]·7H2O

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.     

CH3OH,C2H4在有序和缺陷Nb2O5表面的吸附

为了解氧化铌的表面化学，发展了不同种金属单晶底物定向生长氧化物薄膜技术以克服电子能谱研究氧化铌表面的实验困难．在超高真空系统中用ＨＲＥＥＬＳ，ＵＰＳ研究了ＣＨ３ＯＨ和Ｃ２Ｈ４在氧化铌模型表面的吸附．结果表明，ＣＨ３ＯＨ和Ｃ２Ｈ４在有序表面和缺陷表面的吸附行为表现出很大的不同，氧空穴对吸附有重要影响．