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1.
A selective method has been developed for extraction chromatographic studies of aluminium(III) and its separation from several metal ions with a chromatographic column containing N-n-octylaniline (liquid anion exchanger) coated on silanized silica gel as a stationary phase. The aluminium(III) was quantitatively extracted with the 0.065 mol/L N-n-octylaninine from 0.013 to 0.05 mol/L sodium succinate at a flow rate of 1.0 mL/min. The extracted metal ion has been recovered by eluting with 25.0 mL of 0.05 mol/L hydrochloric acid and estimated spectrophotometrically with aurintricarboxylic acid. The effects of the acid concentration, the reagent concentration, the flow rate and the eluting agents have been investigated. The log-log plots of distribution coefficient (KdAl(III)) versus N-n-octylaniline concentrationin 0.005 and 0.007 mol/L sodium succinate gave theslopes 0.5 and 0.7 respectively and showed theprobable composition of theextracted species was 1:1 (metal to amine ratio) and the nature of extracted species is [RR''NH2+ Al succinate2-] org. .The extraction of aluminium(III) was carried out in the presence of various ions to ascertain the tolerance limit of individual ions. Aluminium(III) has been separated from multicomponent mixtures, pharmaceutical samples and synthetic mixtures corresponding to alloys. A scheme for mutual separation of aluminium(III), indium(III), gallium(III) and thallium(III) has been developed by using suitable masking agents. The method is fast, accurate and precise.  相似文献   

2.
New trinuclear μ3-oxocentered chromium(III, III, III) complexes were obtained by the self-assembly of ferrocenecarboxylate ligands and the Cr3O fragment. The complexes were investigated by fast-atom bombardment (FAB) mass spectrometry, cyclic voltammetry, and electronic and IR spectroscopy. V. I. Vernadskii Institute of General and Inorganic Chemistry, National Academy of Sciences of Ukraine, 32/34 Prospekt Akademika Vernadskogo, Kiev 03142, Ukraine. Translated from Teoreticheskaya i éksperimental'naya Khimiya, Vol. 36, No. 4, pp. 233–237, July–August, 2000.  相似文献   

3.
Cyclic linear-sweep voltammetry was used to study the complexation of Sc(III), Ga(III), In(III) and Ln(III) with eriochrome red B (ERB). It was established that all metal ions investigated form complex compounds with azodye having a mole ratio, M(III):ERB = 1:2. The hydroxo forms of M(III) ions, which take part in interaction with ERB, were determined by the Nazarenko method. The stability constants for the formation of these chelates are nearly the same. It was shown that the reduction of the ligand in the complex does not only depend on the peculiarities of complexation, but the processes occurring in pre-electrode layer also influence it.  相似文献   

4.
The positive, liquid secondary ion (LSI) mass spectra of six cobalt(III) and three chromium(III) (β-diketonates ligand = L?) were examined in a 3-nitrobenzyl alcohol matrix. The complexes of both metals yield clean, matrix-free mass spectra, but there are important differences between them. The cobalt compounds show prominent peaks assignable to the molecular ion, CoL 3 + , of the monomeric chelates, together with abundant dimeric ions, such as Co2L 4 + and Co2L 3 + ; in contrast, chromium complexes show protonated monomers, CrL3H+, in addition to ionized monomers, CrL 3 + , and only minor formation of dimeric ions. The collisionally-activated dissociation (CAD) mass spectrum of Co2L 4 + shows fragmentation to CoL 2 + and Co2L 3 + . That of Co2L 3 + shows fragmentation only to dimeric ions, including Co2L 2 + and, for thienyl or phenyl substituted ligands, to Co2L2Ar+ or Co2LAr+ (Ar = thienyl or phenyl). Neither Co2L 4 + nor Co2L 3 + dissociates to the CoL 3 + ion. The LSI mass spectrum of a mixture of two different cobalt chelates shows dimeric ions containing both types of ligand, which can be explained by ion-molecule reactions in the selvedge region. The differing behaviors of the cobalt and chromium complexes is attributed to the relatively greater stability of the +2 oxidation state for cobalt than for chromium.  相似文献   

5.

The oxidation of triphenylarsine with dioxygen in reaction systems containing some iron compound and Br- anions in acetonitrile leads to the formation of a novel unsymmetrical oxo-bridged diiron(III) complex [(OAsPh3)4 Fe(μ-O)FeBr3]+ [FeBr4]- ·CH3CN, where OAsPh3 is triphenylarsine oxide. The title complex is also formed by direct reaction of iron(III) bromide and OAsPh3 with dioxygen in acetonitrile solution. The crystal structure of the complex was solved by X-ray diffraction techniques. The cation contains two unsymmetrical species with an Fe-O-Fe bond angle of 159.2(2)°; one iron atom is pentacoordinated by four OAsPh3 ligands and a γ-oxo ligand which connects the tetracoordinated Fe atom with the FeBr3O chromophore. Structural parameters and IR spectra of similar complexes are compared and discussed.  相似文献   

6.
IntroductionThesolid phasedeaquation anationreaction[M(NH3 ) 5(H2 O) ]X3 → [M(NH3 ) 5X]X2 +H2 O(M =Co3 + ,Cr3 + orRu3 + andX =Cl- ,Br- orNCS- )hasbeenwidelystudiedsincethenineteensixties .Thethermalandkineticparametershavebeencalculatedandthedifferentmechanismhasbeenproposedandd…  相似文献   

7.
Thermal decomposition of the complexes [LnL8][Cr(NCS)6] (Ln = La3+, Ce3+, Pr3+, Nd3+, Sm3+, Eu3+, Gd3+, Tb3+, Dy3+, Ho3+, Er3+, Tm3+, Yb3+, Lu3+; L = ɛ-C6H11NO) in air and in inert atmosphere was studied by thermogravimetry, X-ray phase analysis, IR spectroscopy, and mass spectrometry. The compositions of gaseous and solid thermolysis products were established. A reversible thermochromic effect was found on heating to 200–210°C.  相似文献   

8.
In this work, we describe the syntheses, characterization, and antifungal activity of [In{S2CNR(R1)}3] (1), [Ga{S2CNR(R1)}3] (2), [Bi{S2CNR(R1)}3] (3), [In{S2CNR(R2)}3] (4), [Ga{S2CNR(R2)}3] (5), and [Bi{S2CNR(R2)}3] (6) {R?=?Me; R1?=?CH2CH(OMe)2; and R2?=?2-methyl-1,3-dioxolane}. All complexes have been characterized using infrared and 1H and 13C spectroscopy, and the structures of 1, 3, 4, and 6 have been authenticated by X-ray diffraction. The In(III)–dithiocarbamate bonding scheme depicts a distorted octahedral with asymmetric In(III)–S bonds and S–In–S angles. A pentagonal bipyramid is observed for the corresponding Bi(III) complexes with intermolecular Bi–S associations through the lone pair of electrons. The antifungal activities of 1–6 have been screened against Aspergillus niger, Aspergillus parasiticus, and Penicillium citrinum, and the results have been compared with those of nystatin and miconazole nitrate, as control drugs.  相似文献   

9.
IntroductionCarbonylgroupsarethemostimportantfunctionalgroupsinorganicsynthesis ,andtheirintroductionbyoxi dationchemistrystartingfromalcoholsisaprocessofmajorimportance .1Earlyprotocolsforthistransformationreliedontheuseofstoichiometricoxidantssuchaschromium(VI)reagentsorMnO2 .2 Withthegoalofimprovingsyn theticefficiencyandavoidingpotentialenvironmentalhaz ards ,prominentsuccessinthisdirectionhasbeenrecentlyachievedbyutilizingmolecularoxygenwithanassistanceofpotenttransitionmetalcompounds.3…  相似文献   

10.
11.
The reaction between LnI3(THF)3.5 and 2 equiv. of {(Me3Si)2(Me2MeOSi)C}K (1) in THF at room temperature yields only the mono-substituted products {(Me3Si)2(Me2MeOSi)C}LnI2(THF)2 [Ln = Y (5), Tm (6)]; under more forcing conditions decomposition occurs. In contrast, the metathesis reaction between TmI3(THF)3.5 and 2 equiv. of the lithium iodide-containing salt {(Me3Si)2(Me2MeOSi)C}K(LiI)x yields the highly unusual separated ion pair complex [[{(Me3Si)2C(SiMe2)}2O]TmI2{Li(THF)3}2][[{(Me3Si)2C(SiMe2)}2O]TmI2] (8). The dianionic ligand in 8 is derived from the coupling of 2 equiv. of (Me3Si)2(Me2MeOSi)C, accompanied by the formal elimination of Me2O. The structures of compounds 5, 6, and 8 have been determined by X-ray crystallography; compound 8 crystallizes as an unusual ion pair, the cation and anion of which differ only in the inclusion of 2 equiv. of Li(THF)3 in the former, bridged to thulium by iodide ions.  相似文献   

12.
13.
The ionic complex [Lu(?-C6H11NO)4(H2O)4][Cr(NCS)6] · 1.5H2O, the first example of coordination of ?-caprolactam to the lutetium atom, was synthesized by the reaction of Lu(NO3)3, K3[Cr(NCS)6], and ?-caprolactam in an aqueous solution. The structure of the complex was established by IR spectroscopy and X-ray crystallography. The crystals are triclinic, space group P \(\bar 1\) T = 100 K, a = 11.9604(3) Å, b = 12.3640(3) Å, c = 18.3506(5) Å, α = 91.3200(10)°, β = 108.6640(10)°, γ = 112.4460(10)°, V = 2343.45(10) Å3, Z = 2, ρcalcd = 1.597 g/cm3, R = 0.0299 for 9839 reflections with F hkl ≥4σ(F). The coordination polyhedron of the lutetium atom is a distorted square antiprism with broken square faces with the oxygen atoms of the organic ligands and water at the vertices. There are weak intramolecular hydrogen bonds N-H…O(H2) in the cation. The coordination polyhedron of the chromium atom is a somewhat distorted octahedron. The thermal stability of the compound was studied in an inert atmosphere and in air.  相似文献   

14.
The effect of the mechanical treatment conditions and of the nature of reactants on the course of the solid-phase reaction of vanadium(III) chloride with sodium β-diketonates and potassium tetramethylheptanedionate, on the yield of the reaction products, and on some properties of the activated mixtures was examined. A method was developed for the synthesis of vanadium(III) β-diketonates by the solid-phase mechanochemical reaction of vanadium(III) chloride with appropriate sodium or potassium β-diketonate, followed by sublimation or extraction.  相似文献   

15.
Ionic self-diffusion coefficients (D) for trivalent radiotracers, lanthanide and actinide ions have been determined in concentrated aqueous solutions of supporting electrolytes of Gd(NO3)3–HNO3 or Nd(ClO3)4–HClO4 up to 1.5 mol L?1 at 298.15 K and pH 2.50 by the open-end capillary method. The data obtained in large range of concentrations, allow to derive the limiting value D°, the validity of the Onsager limiting law and a more extended law. This study contributes to demonstrate similarities in transport and structure properties between 4f and 5f trivalent ions explained by a similar electronic configuration, ionic radius and hydration number. An empirical equation is suggested for predicting ionic hydration number with a good precision.  相似文献   

16.
本文合成了三个以氯冉酸阴离子为桥基的稀土双核配合物,Ln~2(Phen)~4(CA)(NCS)~4(Ln=Nd,Dy,Ho;Phen=菲咯啉;CA=氯冉酸二价阴离子)。通过元素分析,红外光谱,电导,电子吸收光谱及变温(4-300K)磁化率表征了配合物,并由变温磁化率观察到的数据和理论方程通过最小二乘法拟合,得出分子内稀土离子间的相互作用参数:Z'J'=-0.79(Nd),-0.67(Dy),-0.63cm^-^1(Ho);表明稀土离子间存在极弱的反铁磁性交换相互作用。零场分裂参数Δ=-0.16(Nd),-0.76(Dy),-2.55cm^-^1(Ho);g=0.618(Nd),1.739(Dy),1.601(Ho),拟合因子≈10^-^4。  相似文献   

17.
本文合成了三个以氯冉酸阴离子为桥基的稀土双核配合物,Ln~2(Phen)~4(CA)(NCS)~4(Ln=Nd,Dy,Ho;Phen=菲咯啉;CA=氯冉酸二价阴离子)。通过元素分析,红外光谱,电导,电子吸收光谱及变温(4-300K)磁化率表征了配合物,并由变温磁化率观察到的数据和理论方程通过最小二乘法拟合,得出分子内稀土离子间的相互作用参数:Z'J'=-0.79(Nd),-0.67(Dy),-0.63cm^-^1(Ho);表明稀土离子间存在极弱的反铁磁性交换相互作用。零场分裂参数Δ=-0.16(Nd),-0.76(Dy),-2.55cm^-^1(Ho);g=0.618(Nd),1.739(Dy),1.601(Ho),拟合因子≈10^-^4。  相似文献   

18.
Interaction between Eu(III) tris(β-diketonates) and ammonia vapors increases the luminescence of Eu(III). A mechanism for the effect of analyte molecules on the intensification of Eu(III) luminescence is proposed. The mechanism includes the displacement of water molecules from the coordination sphere of europium(III).  相似文献   

19.
The complexation of Eu(III), Am(III) and Cm(III) with dicarboxylate anions with O, N or S donor groups was measured in I=6.60 mol⋅kg−1 (NaClO4) at temperatures of 0–60 °C by potentiometry and solvent extraction. The complexation thermodynamics of these complexes show that their stability is due to highly favorable complexation entropies because the complexation enthalpies are endothermic. Luminescence studies with Eu(III) and Cm(III) were used to measure the hydration numbers of the complexes. NMR spectra of 1H and 13C were used to determine the binding modes of La(III) with the ligands. The formation of 1:1:1 ternary complexes of M(EDTA) with the dicarboxylate ligands was studied to determine changes in coordination of the metal cation with formation of the ternary species. The complexation of ternary complexes changes from bidentate to monodentate as the chain length between the binding sites of the dicarboxylates increases from 1 (malonate) to 4 (adipate). DFT computations were used to confirm the structural aspects of the interaction of these complexes.  相似文献   

20.
Monomolybdenum, monochromium, triosmium and triruthenium clusters, containing weakly coordinated ligands, are valuable starting materials for the preparation of a wide variety of compounds because of the ease with which these ligands can be displaced by another substrate under mild conditions. Four widely used complexes of this type are Mo(CO)6, Cr(CO)6, Os3(CO)12 and Ru3(CO)12 respectively. These complexes react with 2-hydroxy-1-naphthaldimines to give octahedral complexes which are characterized by elemental analyses, i.r. and u.v.–vis. spectra, molar conductances, d.t.a. and t.g.a. analyses, cyclic voltammetry, magnetic and e.s.r. measurements. The molar conductances in DMF solution indicate that the complexes are non-ionic. The i.r. spectra of complexes (3), (7) and (10) show (CO) bands due to bonded CO groups, however complexes (6) and (13) show (CO) bands due to bonded, bridged and terminal CO groups. The g 11-values of the complexes indicate that they have covalent bond character. Also, the electrochemical reduction of the complexes has been discussed.  相似文献   

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