含Keggin类型多酸单元和2-吡啶甲酸的杂化材料的合成、结构及表征

合成了2例基于2-吡啶甲酸（2-PA）和Keggin类型[SiW₁₂O₄₀]^4-、[PMo₁₂O₄₀]^3-多酸单元的有机-无机杂化材料：H₂[（CH₃）₄N]₆[Cu（2-PA）₂（SiW₁₂O₄₀）₂]（1）和（H₃O）[Cu₆（2-PA）₉（PMo₁₂O₄₀）（NO₃）]（2）,并用红外光谱以及X射线衍射对其进行了表征。单晶衍射结构分析表明化合物1为单斜晶系,空间群为P2₁/c,不对称单元中包含1个二价铜离子、2个2-吡啶甲酸配体以及2个Keggin类型[SiW₁₂O₄₀]^4-多酸单元并组成零维结构。循环伏安测试表明化合物1在扫速为100 mV·s^-1时,3组半波电位分别为-270、-516、-708 mV。化合物2为三方晶系,空间群为R3c,不对称单元中包含2个晶体学独立的二价铜离子并且具有2种不同的配位模式,是含六核簇合物单元的二维网络结构。     

基于4-氨基-1,2,4-三唑和多金属氧酸盐为杂化配体的CuⅡ和CuⅠ配合物的水热合成及光催化性能

在水热条件下,制备了2个基于多金属氧酸盐（POM）的Cu^Ⅱ和Cu^Ⅰ新型杂化配合物材料,即[Cu₂（4-NH₂-trz）₄（Mo₈O₂₆）（H₂O）₄]·5H₂O（1）和[Cu₄（4-NH₂-trz）₄Mo₈O₂₆]（2）（4-NH₂-trz=4-氨基-1,2,4-三唑）。通过单晶X射线衍射、傅里叶变换红外光谱和粉末X射线衍射分析确定了它们的结构。在配合物1中,4-氨基-1,2,4-三唑双齿配体连接2个相邻的Cu^Ⅱ中心形成双核结构单元,这些双核结构单元进一步通过Mo₈O₂₆^4-连接形成一维（1D）的杂化配位结构。在配合物2中,4-氨基-1,2,4-三唑双齿配体连接相邻Cu^Ⅰ中心构筑了独特的[Cu₄（4-NH₂-trz）₄]_n一维螺旋链,这些左手和右手的一维螺旋链再通过（β-Mo₈O₂₆）^4-连接形成2D杂化骨架。光催化实验研究表明,样品1和样品2对于不同有机染料（亚甲基蓝（MB）、罗丹明B（RhB）和甲基橙（MO））具有很好的光催化降解能力。     

基于4-氨基-1,2,4-三唑和多金属氧酸盐为杂化配体的CuⅡ和CuⅠ配合物的水热合成及光催化性能

在水热条件下,制备了2个基于多金属氧酸盐（POM）的Cu^Ⅱ和Cu^Ⅰ新型杂化配合物材料,即[Cu₂（4-NH₂-trz）₄（Mo₈O₂₆）（H₂O）₄]·5H₂O（1）和[Cu₄（4-NH₂-trz）₄Mo₈O₂₆]（2）（4-NH₂-trz=4-氨基-1,2,4-三唑）。通过单晶X射线衍射、傅里叶变换红外光谱和粉末X射线衍射分析确定了它们的结构。在配合物1中,4-氨基-1,2,4-三唑双齿配体连接2个相邻的Cu^Ⅱ中心形成双核结构单元,这些双核结构单元进一步通过Mo₈O₂₆^4-连接形成一维（1D）的杂化配位结构。在配合物2中,4-氨基-1,2,4-三唑双齿配体连接相邻Cu^Ⅰ中心构筑了独特的[Cu₄（4-NH₂-trz）₄]_n一维螺旋链,这些左手和右手的一维螺旋链再通过（β-Mo₈O₂₆）^4-连接形成2D杂化骨架。光催化实验研究表明,样品1和样品2对于不同有机染料（亚甲基蓝（MB）、罗丹明B（RhB）和甲基橙（MO））具有很好的光催化降解能力。     

基于双核{Zn2(COO)4}次级构筑单元的二维发光配位聚合物的晶体结构和对Fe3+的检测

使用H2L配体（H2L=2-（1,3-dioxo-1H-benzo[de]isoquinolin-2（3H）-yl） terephthalic acid）和Zn²⁺通过水热反应,合成了一例基于双核{Zn₂（COO）₄}次级构筑单元的二维发光配位聚合物[Zn₂（L）₂（DMSO）₂（DMF）]（1）（DMSO=二甲亚砜,DMF=N,N-二甲基甲酰胺）。拓扑分析表明1结构中的双核{Zn₂（COO）₄}单元可视为4连接节点,并与作为连接子的L^2-形成（4,4）-网拓扑构型。1表现出对Fe³⁺离子的选择性发光猝灭响应,检测限为2.8 μmol·L^-1。1对Fe³⁺的检测具有良好的抗干扰性,且可通过DMF溶剂洗涤实现再生,可多次循环使用。     

基于香豆素Schiff碱的Zn2+、Co2+和Ni2+配合物的合成、晶体结构及光谱性质

合成了3个香豆素Schiff碱单核Zn²⁺、Co²⁺和双核Ni²⁺的配合物，[Zn（L¹）₂]（1）（HL¹=6-（（4-二乙胺基-2-羟基-亚苄基）-氨基）-苯并吡喃-2-酮），[Co（L²）₂]（2）（HL²=6-（（4-甲氧基-2-羟基-亚苄基）-氨基）-苯并吡喃-2-酮），[Ni₂（L³）₂（CH₃OH）₄）]（3）（H₂L³=4-羟基-3-（（4-甲氧基-2-羟基-亚苄基）-氨基）-苯并吡喃-2-酮）。利用元素分析、红外光谱、紫外可见光谱、荧光光谱及X射线单晶衍射分析等手段对其进行了表征。X射线单晶衍射分析结果表明：配合物1和配合物2均为单核结构，由1个金属离子和2个配体单元组成；配合物3具有双核结构，由2个金属离子、2个配体单元及4个配位的甲醇分子组成。配合物1、2和3分别是单斜晶系、三斜晶系和三斜晶系，所属的空间群分别为C2/c、P1和P2₁/n；中心金属Zn²⁺和Co²⁺离子的空间构型为四配位的四面体，Ni²⁺离子的空间构型为六配位的扭曲的八面体。此外，通过对配体HL¹和HL²的紫外可见光谱性质研究发现，在DMF/H₂O（4：1，V/V）溶液中，自由配体HL¹和HL²分别可以选择性识别Hg²⁺和Zn²⁺，通过计算得到其检测限分别为7.45和6.10 μmol·L^-1。荧光性质研究发现在DMF/H₂O（4：1，V/V）溶液中自由配体HL²可以检测Zn²⁺，检测限为2.91 μmol·L^-1。     

基于H3PW12O40·xH2O和3，5-二氨基-1，2，4-三氮唑的POMOF的合成、表征及催化氧化碘离子性能

采用水热法合成了一例结构新颖且罕见的Keggin型多金属氧酸盐基金属有机骨架化合物,即[Cu₄（3,5-datrz）₄][PW^Ⅵ₉W^Ⅴ₃O₃₉]·H₂O （1）,其中3,5-datrz=3,5-二氨基-1,2,4-三氮唑,并通过单晶X射线衍射、傅里叶变换红外光谱、热重分析、粉末X射线衍射和元素分析进行了表征。单晶X射线衍射分析表明：化合物1属于单斜晶系,空间群为C2/c,不对称结构包含2个Cu⁺、2个3,5-datrz配体、0.5个Keggin型磷钨酸阴离子和1个水分子,除结晶水外各组分之间通过共价键连接成Keggin型多金属氧酸盐基金属有机骨架化合物。以化合物1为非均相催化剂,在温度为55℃时催化H₂O₂氧化碘离子反应。结果表明,1催化下的碘单质生成速率为6.11×10^-7 mol·L^-1·s^-1,且重复使用次数达到6次时转化率仍能高达99.6%。     

基于单-和双-三唑衍生物的三个Cu(II)和Cu(I)多金属氧簇基配合物的水热合成及光催化性能

在水热条件下，利用多齿的单-和双-三唑衍生物，制备了3种基于多金属氧簇基（POM）的Cu（Ⅱ）和Cu（I）杂化材料，即{[Cu（L₁）₂（Mo₄O₁₃）]·2H₂O}_n（1），{[Cu_1.5（L₂）（HL₂）（H₂O）（Mo₄O₁₃）]·2H₂O}_n（2），{[Cu₂（L₃）_1.5（Mo₄O₁₃）]·H₂O}_n（3）（L₁=4-pyridine-2-1，2，4-triazole，HL₂=3-（4H-1，2，4-triazol-4-yl）benzoic acid，L₃=trans-4，4''-azo-1，2，4-triazole）。通过单晶X射线衍射、傅里叶变换红外光谱和粉末X射线衍射分析确定了它们的结构。在1中，Mo₄O₁₃^2-阴离子和Cu（Ⅱ）中心通过双齿L₁相互连接，最终形成了二维（2D）POMs基的Cu（Ⅱ）杂化金属-有机骨架。在2中，Mo₄O₁₃^2-阴离子和Cu（Ⅱ）中心通过桥接水原子（O18），双齿HL₂和三齿L₂^-相互连接，最终形成了三维（3D）POMs基的Cu（Ⅱ）微孔金属-有机骨架。在3中，L₃配体桥接相邻的Cu（I）中心和Mo₄O₁₃^2-阴离子，最终形成独特的双重穿插结构的3DPOMs基的Cu（I）杂化配位框架。光催化实验研究表明，样品1~3对于不同有机染料罗丹明B（RhB）、亚甲基蓝（MB）和甲基橙（MO）都具有很好的光催化降解能力。     

基于单-和双-三唑衍生物的三个Cu（Ⅱ）和Cu（Ⅰ）多金属氧簇基配合物的水热合成及光催化性能

在水热条件下,利用多齿的单-和双-三唑衍生物,制备了3种基于多金属氧簇基（POM）的Cu（Ⅱ）和Cu（Ⅰ）杂化材料,即{[Cu（L¹）₂（Mo₄O₁₃）]·2H₂O}_n（1）,{[Cu_1.5（L²）（HL₂）（H₂O）（Mo₄O₁₃）]·2H₂O}_n（2）,{[Cu₂（L₃）_1.5（Mo₄O₁₃）]·H₂O}_n（3）（L₁=4-pyridine-2-1,2,4-triazole,HL₂=3-（4H-1,2,4-triazol-4-yl）benzoic acid,L₃=trans-4,4''-azo-1,2,4-triazole）。通过单晶X射线衍射、傅里叶变换红外光谱和粉末X射线衍射分析确定了它们的结构。在1中,Mo₄O₁₃^2-阴离子和Cu（Ⅱ）中心通过双齿L₁相互连接,最终形成了二维（2D）POMs基的Cu（Ⅱ）杂化金属-有机骨架。在2中,Mo₄O₁₃^2-阴离子和Cu（Ⅱ）中心通过桥接水原子（O18）,双齿HL₂和三齿L₂^-相互连接,最终形成了三维（3D）POMs基的Cu（Ⅱ）微孔金属-有机骨架。在3中,L₃配体桥接相邻的Cu（Ⅰ）中心和Mo₄O₁₃^2-阴离子,最终形成独特的双重穿插结构的3DPOMs基的Cu（Ⅰ）杂化配位框架。光催化实验研究表明,样品1~3对于不同有机染料罗丹明B（RhB）、亚甲基蓝（MB）和甲基橙（MO）都具有很好的光催化降解能力。     

NBO电荷计算对电中性原理的检验

我们在B3LYP/6-31++G（d，p）计算级别下计算了[M（H₂O）₆]³⁺（M=Sc~Co）、[Co（Ⅲ）L₆]（L=F^-、H₂O、NH₃、CN^-），以及基于α-Al₂O₃晶体结构搭建的铝氧簇Al₃O（OH）₇（H₂O）₅（Al₃）和Al₆O₆（OH）₆（H₂O）₅（Al₆）的NBO电荷。除[Co（NH₃）₆]³⁺外，其它化合物均不符合经典教科书中的电中性原理，具有超出-1~+1范围的电荷。此外，我们发现中心原子的电荷受到配位原子种类的极大影响，而这一规律未在电中性原理的表述中。计算结果表明，从[CoF₆]^3-到[Co（CN）₆]^3-，中心离子上所带电荷量从+1.639变化至-1.360，且中心离子上所带电荷随其离子势的增大而降低。另外基于对铝氧簇的计算，我们预测α-Al₂O₃中的Al原子所带电荷应为2.1±0.1。     

含不同芳香取代基的肼基二硫代甲酸甲酯-Ga3+配合物的合成及抑菌活性

设计合成了4种含不同芳香取代基团的肼基二硫代甲酸甲酯配体（2-乙酰基吡啶肼基二硫代甲酸甲酯（L¹-H）、2-甲酰基吡啶肼基二硫代甲酸甲酯（L²-H）、2-甲酰基噻吩肼基二硫代甲酸甲酯（L³-H）、2-甲酰基水杨醛肼基二硫代甲酸甲酯（L⁴-H））的镓配合物,对它们的抑菌活性进行了测试,并讨论了配体分子中不同芳香取代基对配合物抑菌活性的影响。在模拟生理条件下,L与Ga³⁺生成较稳定的单核配合物[Ga（L¹）₂]NO₃（1）、[Ga（L²）₂]NO₃（2）、[Ga（L³）₂]NO₃（3）、[Ga（L⁴）₂]NO₃（4）,各配合物对金黄色葡萄球菌和大肠杆菌表现出比Ga（NO₃）₃·9H₂O强的抑制活性,抑制金黄色葡萄球菌的能力高于大肠杆菌,其中,1和2的活性比相应配体高,其余2个配合物与其配体之间无明显活性差异。L¹和L²分子中吡啶基的较强吸电子效应可能是1和2具有较强抑菌活性的主要原因。4种配合物抑制黑曲霉生长的活性同样高于Ga（NO₃）₃·9H₂O,其中3最强,并显著高于L³,其余配合物与相应配体间无活性差异。     

Recombination of KrD and XeD ions with electrons

Recombination rate coefficients of protonated and deuterated ions KrH⁺, KrD⁺, XeH⁺ and XeD⁺ were measured using Flowing Afterglow with Langmuir Probe (FALP). Helium at 1600 Pa and at temperature 250 K was used as a buffer gas in the experiments. Kr, Xe, H₂ and D₂ were introduced to a flow tube to form the desired ions. Because of small differences in proton affinities of Kr, D₂ and H₂ mixtures of ions, KrD⁺/D₃⁺ and KrH⁺/H₃⁺ are formed in the afterglow plasma, influencing the plasma decay. To obtain a recombination rate coefficient for a particular ion, the dependencies on partial pressures of gases used in the ion formation were measured. The obtained rate coefficients, α_KrD+(250 K) = (0.9 ± 0.3) × 10⁻⁸ cm³ s⁻¹ and α_XeD+(250 K) = (8 ± 2) × 10⁻⁸ cm³ s⁻¹ are compared with α_KrH+(250 K) = (2.0 ± 0.6) × 10⁻⁸ cm³ s⁻¹ and α_XeH+(250 K) = (8 ± 2) × 10⁻⁸ cm³ s⁻¹.     

CO LMR spectrum of14N16O and its analysis with spectra of14N17O and14N18O

LMR spectra for v=1←0 transitions of¹⁴N¹⁶O in X²II_{1/2, 3/2} states were observed at 5.6 μm and 5.4 μm of CO laser. Introducing the advanced isotopic molecular constant scaling function to Hund’s case (a) diatomic structure model, these spectra were analyzed and fitted together with all reliable previous spectral data of¹⁴N¹⁶O as well as¹⁴N¹⁷O and¹⁴N¹⁸O. A full set of precise molecular parameters and their vibrational dependencies have been determined with much higher precision (1–2 orders for most parameters). Many of them have been obtained for the first time. Using isotopic scaling function, the molecular constants of¹⁴N¹⁷O and¹⁴N¹⁸O were deduced.     

Coordinate Structures of PrIII, GdIII, TmIII, and YbIII Complexes with Nitrilotriacetic Acids

The crystal and molecular structures of the [Pr^III(nta)(H₂O)₂]·H₂O (nta = nitrilotriacetic acids), K₃[Gd^III(nta)₂(H₂O)]·6H₂O, and K₃[Yb^III(nta)₂]·5H₂O complexes have been determined by single-crystal X-ray structure analyses. In [Pr^III(nta)(H₂O)₂]·H₂O, the Pr^IIINO₈ part forms a nine-coordinate pseudo-monocapped square antiprismatic structure in which one N and three O atoms are from one nta ligand in the same molecule, three O atoms from another nta ligand in the neighboring molecule and two O atoms from two coordinate water molecules. In K₃[Gd^III(nta)₂(H₂O)]·6H₂O, the [Gd^III(nta)₂(H₂O)^3- complex anion has a nine-coordinate pseudo-monocapped square antiprismatic structure in which each nta acts as a tetradentate ligand with one N atom of the amino group and three O atoms of the carboxylic groups. In K₃[Yb^III(nta)₂]·5H₂O, each nta also acts as a tetradentate ligand with one N atom of amino group and three O atoms of the carboxylic groups, but the [Yb^III(nta)₂ ^3- complex anion has an eight-coordinate structure with a distorted square antiprismatic prism. All the results including those for [Tm^III(nta)(H₂O)₂]·2H₂O confirm the inferences on the coordinate structures and coordination numbers of rare earth metal complexes with the nta ligand.     

Orthogonal Wavelets Analysis of Electroanalytical Signals

ABSTRACT

A signal processing technique based on orthogonal wavelet analysis is applied to process various simulated electroanalytical signals. The results indicate that if the scale parameters are selected, the orthogonal wavelet processing method (OWPM) can remove high-frequency noise. Experimental signal was recorded by computer and used to test the OWPM procedure. After processing with OWPM, the processed data was used to analyze the mechanism of the electrode reactions. Processed results of the experimental data are also satisfactory.     

Analytical methods to determine Po and Pb in marine samples

This paper describes the methods of sampling, preconcentration, chemical separation and final count of ²¹⁰Po and ²¹⁰Pb present in different marine matrices to determine their background levels in a marine ecosystem. Complex, time consuming and selective radioanalytical methods have been used to prepare final clear sources for alpha spectrometry and beta count; in fact, gamma spectrometry, a method direct and non destructive, cannot be taken into account because the ²¹⁰Pb activity is very low which does not allow to carry out sufficiently accurate measurements and ²¹⁰Po is not a gamma emitter but it emits only alpha particle at 5.40 MeV. The results of ²¹⁰Po and ²¹⁰Pb activity concentrations obtained in different marine samples collected in the first two campaigns are still very few to discuss about the ²¹⁰Po and ²¹⁰Pb behavior in marine environment.     

A kinetic study of the oxidation of hydroxamic acids by compounds I and II of horseradish peroxidase: Effect of transition metal ions

Abstract

Oxidation of hydroxamic acids (HXs) generates HNO, and it is not clear whether it is formed also in the presence of metal ions. The kinetics of the oxidation of HXs, such as acetohydroxamic acid, suberohydroxamic acid, and suberoylanilide hydroxamic acid (SAHA), by compounds I and II of horseradish peroxidase (HRP) at pH 7.0 and 25?°C have been studied using rapid-mixing stopped-flow. The kinetics of these reactions were compared to those observed in the presence of Cu(ClO₄)₂, NiSO₄, or ZnSO₄. The rates decrease upon increasing [Cu^II] at constant [HXs], and no oxidation of HX occurs when [HX]/[Cu^II] ≈ 2, implying that HX oxidation in the presence of Cu^II proceeds through the free ligand since the predominant complex is CuX₂. In the case of Ni^II, the oxidation rate decreases upon increasing the ratio [Ni^II]/[HX] beyond 1, where the predominant complex is Ni^IIX⁺, implying that its oxidation is feasible. The effect of Zn^II could be studied only on the rate of HXs oxidation by compound II demonstrating similar behavior to that of Ni^II. HXs were also oxidized catalytically by HRP/H₂O₂ at pH 7.0, demonstrating that metal ions facilitate the formation of HNO while hardly affecting its yield and the extent of HX oxidation.     

The Synthesis of Dibenzo[3n]crown-n by Novel Methods and their Cation Binding Studied by Fluorescence Spectroscopy. Part IV

The dibenzo[3n]crown-n were synthesised from1,2-bis(o-hydroxyphenoxy)ethane obtained from 1,2-bis(o-formylphenoxy)ethane via Bayer-Willigeroxidations with H₂O₂/CH₃COOH in good yields. The cyclic condensation of 1,2-bis(o-hydroxyphenoxy)ethanewith dichlorides, and ditosylates of polyethylene glycols in DMF/Me₂CO₃ gave the macrocyclesdibenzo[15]crown-5, dibenzo[18]crown-6, dibenzo[21]crown-7 anddibenzo[24]crown-8. The structures were identified using IR, mass, ¹H and ¹³C NMR spectroscopy. Therecognition of the molecules for the cations, Li⁺, Na⁺, K⁺, Rb⁺ and Zn²⁺were conducted quantitatively with steady state fluorescencespectroscopy. The 1:1 association constants in acetonitrileshowed a good relation of the appropriate size of the macrocyclic ether towards the fitting cationradii. Namely, dibenzo[15]crown-5 was the best for Li⁺ binding and more than 100 times better thanNa⁺ and K⁺. Dibenzo[21]crown-7 was excellent for Rb⁺ binding while K⁺ is 100 timesless preferred. The largest crown ether studied, dibenzo[24]crown-8, exhibited the order of binding power,Rb⁺ > K⁺ > Na⁺. Zn²⁺ displayed, however, a marked binding with only dibenzo[18]crown-6.p>     

Rotational molecular motion and solvation of Na+ and Cs+ in water-dimethylacetamide. A nuclear magnetic relaxation study

Nuclear magnetic relaxation by intra- and intermolecular quadrupoleelectric field gradient interaction has been used for the study of the systems DMA-water-NaI and DMA-water-CsI at 25°C.¹⁴N relaxation of DMA and²H relaxation of D₂O measured over the complete mixture range reveal the behavior of the rotational molecular motion of the two solvent components. For both solvent components a marked maximum of the reorientational correlation time has been found, reflecting hydrophobic effects and strong DMA-water interaction. The quadrupolar relaxation rates of²³Na⁺ and¹³³Cs⁺ in pure DMA were evaluated giving an indication that the electric solvent dipoles in the solvation shell are not located on positions of cubic symmetry. A quantitative study of preferential solvation of the cations in the mixed solvent has been performed by using the H₂O-D₂O isotope effect on²³Na⁺ and¹³³Cs⁺ relaxation. For both cations an obviously typical change in the selectivity occurs. In the range l>x _{H2 O}>0.7 we find weak preferential hydration, but in the range 0.7>xH ₂ O>0 strong preferential solvation by DMA is reflected.     

The preparation and analysis of fluoro-polyphosphates by F, P, 2D F-P HETCOR and 2D P-P COSY NMR

A complex mixture of fluoro-polyphosphates (FPPs) and polyphosphates was prepared by heating a mixture of NaF and sodium tripolyphosphate (STPP) at 600 °C in nitrogen atmosphere. Two-dimensional ³¹P-¹⁹F heteronuclear correlation spectroscopy (HETCOR) NMR was developed in identifying the atomic connection between F and P in the mixed FPPs. ¹⁹F, ³¹P and ³¹P-³¹P correlation spectroscopy (COSY) NMR methods were employed to identify the components of the mixture and measure the chain length of each FPP ingredient. NMR results clearly demonstrated that the mixture contains four kinds of fluoro-phosphates with different chain length of polyphosphate, which are monofluoro-phosphate (MFP), monofluoro-dipolyphosphate (MFDPP), monofluoro-tripolyphosphate (MFTPP) and difluoro-tripolyphosphate (DFTPP). Other phosphates and polyphosphates also were found in the mixture.     

Possibilities of multinuclear NMR in the chemistry of heteroorganic compounds

Results of multinuclear NMR studies of some heteroorganic compounds have been presented.According to a report at the conference «Current problems of organometallic chemistry» (May 8–13,1994, Moscow).Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 614–616, April, 1994.