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1.
本文考虑相对论效应并应用密度泛函理论(DFT)研究水溶液中UO2Xn(H2O)5-n(X=F,Cl,Br;n=1~4)和UO2Xn(X=F,Cl,Br;n=1~6)一系列水合和非水合铀酰化合物的结构和紫外吸收光谱性质。将这一系列物质命名为Xnm(X为F,Cl,和Br;n为卤素配体个数,m为水分子配体的个数)。在水溶液中,溶剂化效应采用类导体屏蔽模型(COSMO)并采用SAS溶剂接触曲面构造空穴模拟水溶剂对配合物的作用。配合物的紫外光谱性质采用考虑旋-轨耦合相对论效应的含时密度泛函(SO-TD-DFT)进行计算。U=O键随着F配体数目的增加而明显伸长,然而随Cl和Br配体数目的增加变化较小。随X配体数目的增加和水分子参与配位,铀与X的结合能逐渐减弱。配合物的紫外光谱计算表明铀酰氟的各种配合物并不出现特征吸收峰,而铀酰氯和铀酰溴的各种配合物均有特征吸收光谱。通过分子轨道分析可以很好解释光谱所体现的特征。  相似文献   

2.
Palladium(II) complexes of biacetylmonoxime arylhydrazones (HL, aryl = phenyl, o-, m-, and p-tolyl, p-chloro- and p-nitrophenyl) and biacetylmonoxime N′-methyl-phenylhydrazone (HL′) have been prepared and characterized. The hydrazomines, HL and HL′, are coordinated through oxime- and hydrazone-nitrogen atoms as a bidentate ligand in the complexes [PdX2(HL or HL′)] (X = halogen atom) formed under neutral conditions. Under basic conditions the deprotonated complexes [PdX(L or L′)] are obtained. Deprotonation occurs at the oxime group of HL′ and the ligand remains coordinated through oxime- and hydrazone-nitrogen atoms. The other hydrazoximes (HL) are cyclopalladated at the ortho position of the benzene rings and act as an NNC terdentate ligand in the deprotonated complexes [PdXL].  相似文献   

3.
Summary Uranyl acetate dihydrate reacts with several hydrazone-oximes, derived from aliphatic (mon-annd di-) hydrazides and 2,3-butanedione monoxime in the absence of NaOAc, to form complexes of general formulae [UO2(HL)2] and [UO2(HL)2SZ] (where H2L=aliphatic acid monohydrazone-oximes; S=EtOH and Z=H2O). With aliphatic acid dihydrazone and monomaleoyl-hydrazone-oximes, different complexes have been synthesized in 50% EtOH and in the absence of NaOAc. The products have been characterized by elemental analyses, molar conductivities, spectral (u.v., i.r., n.m.r.), pH, conductometric titrations, molecular weights and magnetic measurements. I.r. spectral data indicate that the aliphatic hydrazone-oximes, except monomaleoyl-hydrazone-oxime, behave in a similar way to tridentate ligandsvia the azomethine nitrogen and the NOH groups, with replacement of a hydrogen atom from the latter group. On the other hand, malonyl dihydrazone- and adipoyldihydrazone-oximes coordinate in a bi-, and tridentate manner, respectively, towards one uranyl ion, while monomaleoyl- and oxaloyldihydrazone-oximes behave in a penta-and hexadentate fashion, respectively, towards two uranyl ions. Elemental analyses, molecular weight measurements as well as spectral data confirm the existence of a binuclear complex for monomaleoyl- and oxaloyldihydrazone-oximes, whereas a monomer for the rest. Finally, the role of solvent, absence of NaOAc and the type of ligand on the structure of the complexes are discussed.  相似文献   

4.
The syntheses and structural studies of an [O,N,O,N′]-type phenolic ligand [(N’,N’-bis(2-hydroxy-3-methoxy-5-(propen-2-yl)benzyl)-N-(2-aminoethyl)morpholine), (H2L) and two new uranyl complexes of this ligand are described. The reaction between uranyl nitrate hexahydrate and H2L in a 1:2 M ratio (M to H2L) results in a uranyl complex of the formula [UO2(HL)(NO3)(H2O)] (1). In the presence of a base (triethylamine), with the same molar ratio, the uranyl complex [UO2(HL)2]·2CH3CN (2) is formed. The molecular structures H2L, 1 and 2 were verified by X-ray crystallography. Both uranyl complexes are zwitterions with a neutral net charge. A comprehensive NMR-structural analyses of all compounds were performed in CDCl3, DMSO-d6 and pyridine-d5. Complex 2 dissociates in all the studied NMR-solvents, forming a 1:1 complex and free ligand, but according to the spectra the formed complexes are not alike. The results of the ability of the ligand to extract the uranyl ion from water into dichloromethane are also presented.  相似文献   

5.
以3-乙基-2-乙酰吡嗪N(4)-(对甲苯)氨基硫脲(HL)为原料,合成了[Ga(L)2]NO3·4CH3OH(1)和[In(L)2]NO3·1.75CH3OH(2)两种新型配合物,并进行了X射线衍射分析表征。结果表明,配合物1和配合物2同构但具有不同数目的结晶甲醇分子。每个配合物的金属中心被2个拥有[N2S]供体的配体阴离子包围,采取扭曲的八面体配位几何。此外,荧光光谱表明配合物与DNA的相互作用强于配体。  相似文献   

6.
Acetylpyridine benzoylhydrazone and related ligands react with common dioxouranium(VI) compounds such as uranyl nitrate or [NBu4]2[UO2Cl4] to form air‐stable complexes. Reactions with 2, 6‐diacetylpyridinebis(benzoylhydrazone) (H2L1a) or 2, 6‐diacetylpyridinebis(salicylhydrazone) (H2L1b) give yellow products of the composition [UO2(L1)]. The neutral compounds contain doubly deprotonated ligands and possess a distorted pentagonal‐bipyramidal structure. The hydroxo groups of the salicylhydrazonato ligand do not contribute to the complexation of the metal. The equatorial coordination spheres of the complexes can be extended by the addition of a monodentate ligand such as pyridine or DMSO. The uranium atoms in the resulting deep‐red complexes have hexagonal‐bipyramidal coordination environments with the oxo ligands in axial positions. The sterical strains inside the hexagonal plane can be reduced when two tridentate benzoylhydrazonato ligands are used instead of the pentadentate 2, 6‐diacetylpyridine derivatives. Acetylpyridine benzoylhydrazone (HL2) and bis(2‐pyridyl)ketone benzoylhydrazone (HL3) deprotonate and form neutral, red [UO2(L)2] complexes. The equatorial coordination spheres of these complexes are puckered hexagons. X‐ray diffraction studies on [UO2(L1a)(pyridine)], [UO2(L1b)(DMSO)], [UO2(L2)2] and [UO2(L3)2] show relatively short U—O bonds to the benzoylic oxygen atoms between 2.328(6) and 2.389(8) Å. This suggests a preference of these donor sites of the ligands over their imino and amine functionalities (U—N bond lengths: 2.588(7)—2.701(6) Å ).  相似文献   

7.
The syntheses and crystal structures of four new uranyl complexes with [O,N,O,N′]-type ligands are described. The reaction between uranyl nitrate hexahydrate and the phenolic ligand [(N,N-bis(2-hydroxy-3,5-dimethylbenzyl)-N′,N′-dimethylethylenediamine)], H2L1 in a 1:2 molar ratio (M to L), yields a uranyl complex with the formula [UO2(HL1)(NO3)] · CH3CN (1). In the presence of a base (triethylamine, one mole per ligand mole) with the same molar ratio, the uranyl complex [UO2(HL1)2] (2) is formed. The reaction between uranyl nitrate hexahydrate and the ligand [(N,N-bis(2-hydroxy-3,5-di-t-butylbenzyl)-N′,N′-dimethylethylenediamine)], H2L2, yields a uranyl complex with the formula [UO2(HL2)(NO3)] · 2CH3CN (3) and the ligand [N-(2-pyridylmethyl)-N,N-bis(2-hydroxy-3,5-dimethylbenzyl)amine], H2L3, in the presence of a base yields a uranyl complex with the formula [UO2(HL3)2] · 2CH3CN (4). The molecular structures of 14 were verified by X-ray crystallography. The complexes 14 are zwitter ions with a neutral net charge. Compounds 1 and 3 are rare neutral mononuclear [UO2(HLn)(NO3)] complexes with the nitrate bonded in η2-fashion to the uranyl ion. Furthermore, the ability of the ligands H2L1–H2L4 to extract the uranyl ion from water to dichloromethane, and the selectivity of extraction with ligands H2L1, H3L5 (N,N-bis(2-hydroxy-3,5-dimethylbenzyl)-3-amino-1-propanol), H2L6 · HCl (N,N-bis(2-hydroxy-5-tert-butyl-3-methylbenzyl)-1-aminobutane · HCl) and H3L7 · HCl (N,N-bis(2-hydroxy-5-tert-butyl-3-methylbenzyl)-6-amino-1-hexanol · HCl) under varied chemical conditions were studied. As a result, the most efficient and selective ligand for uranyl ion extraction proved to be H3L7 · HCl.  相似文献   

8.
Several new two‐ligand complexes of zinc(II) with the aromatic N, N‐donor ligands 2, 2′‐bipyridine or 1, 10‐phenanthroline and one of three different α‐hydroxycarboxylates (HL′) derived of the α‐hydroxycarboxylic acids (H2L′) (2‐methyllactic, H2mL; mandelic, H2M or benzilic, H2B) were prepared. The compounds of formula [Zn(HL′)2(NN)]·nH2O (HL′ = HM, HB) were isolated as white powders and characterized by elemental analysis, IR spectroscopy and thermogravimetric analysis. The complexes of general formula [Zn(HL′)(NN)2](HL′)·nH2O (HL′ = HmL, HM) and [Zn(HB)2(NN)2], were obtained as single crystals and were characterized by elemental analysis, IR spectroscopy, thermogravimetric analysis and X‐ray diffractometry. In all cases, the zinc atom is in a distorted octahedral environment. In [Zn(HL′)(NN)2](HL′)·nH2O the α‐hydroxycarboxylato ligands behave as bidentate chelating monoanion and an α‐hydroxycarboxylate as counterion is also present. In [Zn(HB)2(NN)2], the monoanionic benzilato ligand behaves as monodentate through one oxygen atom of the carboxylate function. The effect of the classical and no‐classical hydrogen bonding and of the π‐π and C‐H…π interactions in the 3D supramolecular arrangement of these molecular complexes is analyzed.  相似文献   

9.
Three disulfoxide uranyl complexes [UO2(DBSOB)(NO3)2] n (1), [UO2(DBM)2]2(DBSOB) (2), and [UO2(PMBP)2]2(DBSOB) (3) (DBSOB = 1,4-di(butylsulfinyl)butane, HDBM = dibenzoylmethane, HPMBP = 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone) were synthesized and characterized. The [UO2(NO3)2] groups are connected by bridging disulfoxide ligands DBSOB to form a 1-D zigzag chain in 1. Two [UO2(DBM)2] or [UO2(PMBP)2] groups are connected by a bridging DBSOB to form the dimeric structures of 2 or 3, respectively. Complexes 1, 2, and 3 are the first structurally characterized disulfoxide–actinide compounds. Thermal stabilities of 1, 2, and 3 were investigated.  相似文献   

10.
New pincer ligand, 6-hydroxymethylpyridine-2-carboxylic acid methyl ester, HL, and its bipositive, tripositive and uranyl metal complexes have been synthesized and characterized by elemental and thermal analyses, IR, diffuse reflectance and 1H NMR spectra, molar conductance and magnetic moment measurements. The downfield shift of the aliphatic OH signal (from 3.87 vs. 2.96 ppm in the ligand) upon complexation indicates the coordination by protonated aliphatic OH group. Zn(II) and UO2(II) complexes are found to be diamagnetic as expected. The low molar conductance values indicate that Ni(II) and Zn(II) complexes are non electrolytes; Fe(II), Co(II), Cu(II) and UO2(II) complexes are 1:2  electrolytes while Fe(III) complex is a 1:3 electrolyte. The general compositions of the complexes are found to be [M(HL)X2nH2O where M=Ni(II) (X=Cl, n=1) and Zn(II) (X=Br, n=0); and [M(HL)2]Xm·nH2O where M=Fe(II) (X=Cl, m=2, n=0), Fe(III) (X=Cl, m=3, n=4), Co(II) (X=Cl, m=2, n=0), Cu(II) (X=Cl, m=2, n=0) and UO2(II) (X=NO3, m=2, n=0). The thermal behaviour of the complexes has been studied and different thermodynamic parameters are calculated using Coats-Redfern method.  相似文献   

11.
The syntheses of five new aminoalkylbis(phenolate) ligands (as hydrochlorides) and their uranyl complexes are described. The reaction between uranyl nitrate hexahydrate and phenolic ligand [(N,N-bis(2-hydroxy-5-tert-butyl-3-methylbenzyl)-1-aminopropane) · HCl], H2L1 · HCl, forms a uranyl complex [UO2(HL1)2] · 2CH3CN (1). The ligand [(N,N-bis(2-hydroxy-5-tert-butyl-3-methylbenzyl)-1-aminobutane) · HCl], H2L2 · HCl, forms a uranyl complex with a formula [UO2(HL2)2] · 2CH3CN (2). The ligand [(N,N-bis(2-hydroxy-5-tert-butyl-3-methyl benzyl)-1-aminohexane) · HCl], H2L3 · HCl, yields a uranyl complex with a formula [UO2(HL3)2] · 2CH3CN (3) and the ligand [(N,N-bis(2-hydroxy-5-tert-butyl-3-methylbenzyl)-cyclohexylamine) · HCl], H2L4 · HCl, yields a uranyl complex with a formula [UO2(HL4)2] (4). The ligand [(N,N-bis(2-hydroxy-5-tert-butyl-3-methylbenzyl)-benzylamine) · HCl], H2L5 · HCl, forms a uranyl complex with a formula [UO2(HL5)2] · 2MeOH (5). The molecular structures of 1, 2′ (2 without methanol), 3, 4 and 5 were verified by X-ray crystallography. The complexes 15 are neutral zwitterions which form in a molar ratio of 1:2 (U to L) in the presence of a base (triethylamine) and bear similar mononuclear, distorted octahedral uranyl structures with the four coordinating phenoxo ligands forming an equatorial plane and resulting in a centrosymmetric structure for the uranyl ion. In uranyl ion extraction studies from water to dichloromethane with ligands H2L1 · HCl–H2L5 · HCl, the ligands H2L2 · HCl and H2L4 · HCl are the most effective ones.  相似文献   

12.
Simple and versatile routes to the functionalization of uranyl‐derived UV–oxo groups are presented. The oxo‐lithiated, binuclear uranium(V)–oxo complexes [{(py)3LiOUO}2(L)] and [{(py)3LiOUO}(OUOSiMe3)(L)] were prepared by the direct combination of the uranyl(VI) silylamide “ate” complex [Li(py)2][(OUO)(N”)3] (N”=N(SiMe3)2) with the polypyrrolic macrocycle H4L or the mononuclear uranyl (VI) Pacman complex [UO2(py)(H2L)], respectively. These oxo‐metalated complexes display distinct U? O single and multiple bonding patterns and an axial/equatorial arrangement of oxo ligands. Their ready availability allows the direct functionalization of the uranyl oxo group leading to the binuclear uranium(V) oxo–stannylated complexes [{(R3Sn)OUO}2(L)] (R=nBu, Ph), which represent rare examples of mixed uranium/tin complexes. Also, uranium–oxo‐group exchange occurred in reactions with [TiCl(OiPr)3] to form U‐O? C bonds [{(py)3LiOUO}(OUOiPr)(L)] and [(iPrOUO)2(L)]. Overall, these represent the first family of uranium(V) complexes that are oxo‐functionalised by Group 14 elements.  相似文献   

13.
Four Co(II) complexes, [Co(HL)2](OAc)2, [Co(HL)2Cl2], [Co(HL)2(MeOH)2](NO3)2, and [Co2(HL)4(SO4)2] (HL = acetone-N(4)-phenylsemicarbazone) were synthesized and characterized by physicochemical and spectroscopic methods. The magnetic susceptibility measurements indicate that the complexes are paramagnetic with three unpaired electrons. In all the complexes, the semicarbazone is coordinated as a neutral bidentate ligand. The structure of [Co(HL)2(MeOH)2](NO3)2 was confirmed by single crystal X-ray crystallography. The ligand is neutral and bidentate, being coordinated to the cobalt atom through the carbonyl oxygen and the azomethine nitrogen. Intermolecular hydrogen bonding and C–H···π interactions combine to stabilize the crystal structure. The ligand and its two complexes [Co(HL)2Cl2] and [Co(HL)2(MeOH)2](NO3)2 were screened for their antibacterial and antifungal activities using disk diffusion methods.  相似文献   

14.
The formation of hydrolysed uranyl(VI) species in UO2X zeolites prepared by various methods has been investigated by Raman spectroscopy. Ion-exchange in aqueous (pH>3) and non-aqueous (anhydrous methanol and uranyl nitrate melts) media resulted in the formation of hydroxy-bridged complexes such as [(UO2)3(OH)4]2+, [(UO2)3(OH)5]+, and [(UO2)4(OH)7]+. Ion-exchange in more acidic media (initial pH < 3) was accompanied by the formation of a disordered phase incorporating UO3, following extensive collapse of the zeolite framework structure. Cation speciation in the UO2X system is compared to that in UO2Y zeolites.  相似文献   

15.
Two novel isopropylamine‐templated uranyl chromates, [(CH3)2CHNH3]3[(UO2)3(CrO4)2O(OH)3] ( 1 ) and [(CH3)2CHNH3]2[(UO2)2(CrO4)3(H2O)] ( 2 ) were prepared by hydrothermal method at 100 °C. The compounds were characterized by electron microprobe analysis and X‐ray diffraction crystal structure analysis [ 1 : trigonal, P31m, a = 9.646(4), c = 8.469(4) Å, V = 682.4(5) Å3; 2 : monoclinic, P21/c, a = 11.309(3), b = 11.465(3), c = 17.055(5) Å, β = 99.150(6)°, V = 2183.2(11) Å3]. The structure of 1 is based upon trimers of uranyl bipyramids interlinked by CrO4 tetrahedra to form [(UO2)3(CrO4)2O(OH)3]3– layers, whereas, in the structure of 2 , UO7 and UO6(H2O) pentagonal bipyramids are linked through CrO4 tetrahedra into the [(UO2)2(CrO4)3(H2O)]2– layers. The structures show many similarities to related uranyl selenate compounds, thus providing additional data on similarities and differences between uranyl sulfates, chromates, selenates, and molybdates.  相似文献   

16.
Summary Several new dioxouranium(VI) complexes with the tridentate dibasic Schiff bases derived from salicylaldehyde, 5-chloro-, 5-bromo-, 5-nitro-, 3,5-dichloro-, 4-methoxy-, 5-methoxy- and 3-ethoxysalicylaldehyde and 2-hydroxy-1-naphthaldehyde ando-aminobenzyl alcohol, have been synthesized from uranyl acetate dihydrate and the Schiff base in methanol. The complexes are of the type UO2(AAA). MeOH (where AAAH2 = a tridentate dibasic Schiff base). The complexes have been characterized by elemental analyses, i.r. and electronic spectra, conductance, magnetic susceptibility and molecular weight measurements. Thev (U=O) stretching frequency of the complexes occurs atca. 900 cm–1 and the U-O distance is 1.74Å. The complexes are monomers, diamagnetic and octahedral.  相似文献   

17.
Abstract

The literature for the years 1965–1987 has been searched for all significant papers which refer to the vibrational spectra of metal complexes of aniline and substituted anilines. These papers have been reviewed with particular reference to isotopic labelling and metal ion substitution studies as assignment techniques and to the structural and bonding information which can be derived from the spectra. Compounds of the following classes are included: [M(an)2X2] (M = Mn, Co, Ni, Cu, Zn, Cd, Hg; an = aniline, X - Cl, Br, I, NCS); cis- and trans-[Pt(an)2X2] (X = Cl, Br, I, NO2); [M(R-an)2X2] (M = Mn, Co, Ni, Cu, Zn; R-an = o-, m- and p-toluidine and other substituted anilines; X = Cl, Br, I); aniline adducts of metal β-ketoenolates; the complexes trans-[PtL(R-an)X2] (L = CH2?CH2 or CO, R-an = aniline or a substtuted aniline, X = Cl, Br); and other miscellaneous systems comprising aniline as a ligand.  相似文献   

18.
Although potassium, rubidium, and cesium uranyl nitrate have been characterized a long time ago, the crystal structure and properties of the homologous sodium compounds has not been reported yet. Na[UO2(NO3)3] crystallizes in a unique structure [Pearson code cP72, cubic, P213, no. 198, Z = 4, a = 10.6324(14) Å, 938 unique reflections with Io > 2σ(Io), R1 = 0.0379, wR2 = 0.0947, GooF = 1.092, T = 293 K]. The structure is characterized by an open framework built by interconnected helical chains formed by {UO8} and {NaO6} units. The vibrational and optical (UV/Vis absorption and luminescence) spectra match well with those of the higher alkali metal uranyl nitrates.  相似文献   

19.
The electronic structure of various complexes of pentavalent uranyl species, namely UO2+, is described, using DFT methods, with the aim of understanding how the structure of the ligands may influence the localisation of the unpaired 5f electron of uranium (V) and, finally, the stability of such complexes towards oxidation. Six complexes have been inspected: [UO2py5]+ (1), [(UO2py5)KI2] (2), [UO2(salan-tBu2)(py)K] (3), [UO2(salophen-tBu2)(thf)K] (4), [UO2(salen-tBu2)(py)K] (5), [and UO2-cyclo[6]pyrrole]1? (6), chosen to explore various ligands. In the five first complexes, the UO2+ species is well identified with the unpaired electron localized on the 5f uranium orbital. Additionally, for the salan, salen and salophen ligands, some covalent interactions have been observed, resulting from the presence of both donor and acceptor binding sites. In contrast, the last complex is best described by a UO22+ uranyl (VI) coordinated by the anionic radical cyclopyrrole, the highly delocalized π orbitals set stabilizing the radical behaviour of this ligand.  相似文献   

20.
Summary Complexes of CuII, NiII, CoII, ZnII, CdII and HgII with 4-benzamido-1-o-aminoacetophenone-3-thiosemicarbazone (H2BATS) are reported and have been characterized by elemental analyses, molar conductivities, magnetic moments, spectral (visible, i.r.) and thermal (d.t.a., t.g., d.t.g.) measurements. I.r. spectra show that H2BATS behaves as a dianionic, monoanionic or neutral tetradentate ligand or as a monoanionic tridentate ligand. [Cu2(H2BATS)Cl2]·2H2O and [Cu2(H2BATS)Ac2]·2H2O complexes are diamagnetic while [Co(HBATS)OH]·2H2O and [Ni(HBATS)OH]·2H2O are octahedral. All the complexes are non-electrolytes. Generally, the solid metal acetate complexes have a unique decomposition exotherm profile which can be used as a rapid and sensitive tool for the detection of acetate-containing complexes.  相似文献   

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