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Zusammenfassung Es wurde die ionophoretische Trennung von ReCl6 2–, ReBr6 2– und ReO4 unter Verwendung verschiedener Papiersorten untersucht. Am geeignetsten erwies sich das Papier 2045 b Gl von Schl. & Sch.
Summary The ionophoretic separation of ReCl6 2–, ReBr6 2–, and ReO4 has been examined using different kinds of paper. Best results have been obtained with the paper 2045 b Gl from Schleicher & Schüll.


Herrn Prof. G. Brauer danke ich für Förderung. Für die Überlassung von Rheniumverbindungen bin ich der Fa. W. C. Heraeus, Hanau, verpflichtet. Die Neutronenaktivierung wurde freundlicherweise von den Herren Dr. Marth und Dr. Köhler von der Reaktorstation in Garching bei München vorgenommen. Das Bundesministerium für Atomkernenergie und Wasserwirtschaft unterstützte die Untersuchung durch eine Sachbeihilfe.  相似文献   

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Zusammenfassung Es wird über eine Methode zur Bestimmung von Halogenidionen in Halogenidgemischen berichtet. Die Endpunktindikation erfolgt nach dem Prinzip der Polarisationsspannungstitration und liefert scharf ausgeprägte Titrationsendpunkte in der Reihenfolge der Schwerlöslichkeit der Ag-Halogenide. Insbesondere wird auch der für Serienanalysen erforderlichen Einfachheit und geringen Störanfälligkeit Rechnung getragen. Das Verfahren eignet sich für die Analyse anorganischer Halogenidgemische, für die Bestimmung von CN- und SCN -Ionen und für die Analyse organischer Halogenverbindungen im Makro- und Halbmikromaßstab nach deren Aufschluß. Die Meßanordnung kann außerdem für die Bestimmung von Kalium und für die Endpunktindikation einiger chelatometrischer Titrationen eingesetzt werden.
Summary A method is described for the determination of halogenide in mixtures of halogenides. End points are sharply indicated by the polarisation titration technique in the order of solubility of the silver halogenides. The method is suitable for the analysis of mixtures of inorganic halogenides, for the determination of CN and SCNions, and for the analysis of organic halogen compounds in macro and semimicro scale after decomposition. For routine analyses it offers the advantage of being simple and only slightly liable to interferences. Moreover, the assembly can be used for the determination of potassium and for the end point indication in some chelatometric titrations.
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The interaction between the radical anions C60 ·− and divalent d- and f-metal (Co, Fe, Ni, Mn, Eu, Cd) cations in DMF and acetonitrile-benzonitrile (AN-BN) mixture was studied. Black solid polycrystalline salts (C60 ·−)2{(M2+)(DMF) x } (x = 2.4–4, 1–6) containing the radical anions C60 ·− and metal(ii) cations solvated by DMF were prepared for the first time and their optical and magnetic properties were studied. The salts containing Co2+, Fe2+, and Ni2+ are characterized by antiferromagnetic interactions between the radical anions C60 ·−, which result in unusually large broadening of the EPR signal of C60 ·− upon lowering the temperature (from 5.55–12.6 mT at room temperature to 35–40 mT at 6 K for Co2+ and Ni2+). The salts containing Mn2+ and Eu2+ form diamagnetic dimers (C60 )2, which causes a jumpwise decrease in the magnetic moment of the complexes and disappearance of the EPR signal of C60 ·− in the temperature range 210–130 K. A feature of salt 6 is magnetic isolation of the radical anions C60 ·− due to the presence of diamagnetic cation Cd2+. The salts prepared are unstable in air and decompose in o-dichlorobenzene or AN. Reactions of C60 ·− with metal(ii) cations in AN-BN mixture result in decomposition products of the salts that contain neutral fullerene dimers and metals solvated by BN. Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 9, pp. 1909–1919, September, 2008.  相似文献   

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Type studies on competitive polyatomic anion versus acetonitrile coordination in the self-assembly of a series of [Ag2(X) m (bip)(NCCH3) n ](X)2−m (X = NO3 , CF3SO3 , ClO4 , BF4 , and PF6 ; m = 0, 2; n = 0, 2, 4; bip = 1,4-bis(2-isonicotinoyloxyethyl)piperazine) were carried out. Each bip spacer acts as an N4 tetradentate ligand and is linked to four silver(I) centers through two pyridine and two piperazine moieties, producing a double strand consisting of two 20-membered ring units. The coordinating environment around the silver(I) center is subtly determined by the competition of the polyatomic anions with acetonitrile, that is, by the Ag···NCCH3 versus Ag···X interactions. The coordinating ability of acetonitrile is inversely proportional to the order of the coordination ability of the Hoffmeister series of polyatomic anions, NO3  ≫ CF3SO3  > ClO4  > BF4  ≫ PF6 .  相似文献   

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The oxidation of MnEDTA2–. (EDTA=ethylenediaminetetra-acetate) by hexachloroiridate(IV) has been studied in concentrated electrolyte solutions at 298 K. The estimation of the activity coefficients of the species from the Stokes-Robinson hydration theory indicates that the observed salt effects have their origin in a greater destabilization of the initial state with respect to the transition state when increasing salt concentration. MnEDTA2– (EDTA= ) (IV) . -, , .  相似文献   

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Three new heteronuclear complexes [Ru(NO)(NO2)4(OH)M(Py)3] (M = Co2+, Ni2+, Zn2+) were synthesized and structurally characterized. In all compounds, the [Ru(NO)(NO2)4(OH)] fragment is coordinated to the M atom by a bridging OH and two bridging NO2 groups. The coordination environment of the metal also includes three pyridine nitrogen atoms. Thermal decomposition of cobalt and nickel complexes in an inert atmosphere yields bimetallic solid solutions. Original Russian Text ? G.A. Kostin, A.O. Borodin, Yu.V. Shubin, N.V. Kurat’eva, V.A. Emelyanov, P.E. Plyusnin, M.R. Gallyamov, 2009, published in Koordinatsionnaya Khimiya, 2009, Vol. 35, No. 1, pp. 57–64.  相似文献   

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The complexes [Ph3BuP]2+[Bi2I8 · 2Me2C=O]2− (II) and [Ph3BuP]2+[Bi2I8 · 2Me2S=O]2− (III) are synthesized by the reactions of triphenyl(n-butyl)phosphonium iodide (I) with bismuth iodide in acetone and dimethyl sulfoxide. In the cations of complexes I–III, the P atoms have a distorted tetrahedral coordination (CPC angles 106.3(2)°–112.0(3)°). The butyl group in cation I is disordered over two positions. In the binuclear centrosymmetric anions of structures II and III, the octahedrally coordinated bismuth atoms are linked in pairs by two bridging (br) iodine atoms (Bi-Ibr 3.1508(7) and 3.2824(8) ? in compound II, 3.1961(3) and 3.3108(3) ? in complex III), which are coplanar to four terminal (t) iodine atoms (Bi-It 2.9260(7) and 2.9953(6) ? in complex II, 2.9206(3) and 2.9786(3) ? in complex III). The two remaining positions at the bismuth atom are occupied by the iodine atom (Bi-It 2.8531(7) ? in complex II, 2.8984(3) ? in complex III) and O atom of the organic molecule (Bi-O 2.747(6) ? in complex II, 2.507(3) ? in complex III). Original Russian Text ? V.V. Sharutin, I.V. Egorova, N.N. Klepikov, E.A. Boyarkina, O.K. Sharutina, 2009, published in Koordinatsionnaya Khimiya, 2009, Vol. 35, No. 3, pp. 188–192.  相似文献   

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The reactions of tetraphenylantimony with hexachloroplatinic and chloroauric acids in benzene afford bis(tetraphenylantimony) hexachloroplatinate (I) and tetraphenylantimony tetrachloroaurate (II), respectively. Compound II is also synthesized from tetraphenylantimony chloride and chloroauric acid in acetone. Bis(tetraphenylantimony) hexachlorostannate (III) is synthesized from tin dichloride and tetraphenylantimony chloride in acetone or from tin tetrachloride and tetraphenylantimony chloride in benzene. The crystal structures of compounds I–III are determined by X-ray diffraction analysis. The antimony atoms in the [Ph4Sb]+ cations have a distorted tetrahedral coordination (CSbC bond angles range from 105.7(1)° to 118.5(1)° (I), from 106.2(3)° to 114.4(3)° (II), and from 106.0(1)° to 117.1(1)° (III)). The Sb-C bond lengths vary in intervals of 2.094(2)–2.098(2), 2.087(7)–2.111(7), and 2.093–2.100(3) ?, respectively. The coordination of the Pt and Sn atoms in complexes I and III is close to an ideal octahedral coordination with ClPtCl and ClSnCl bond angles of 88.68(2)°–91.32(3)° and 88.84(3)°–91.16(3)°, respectively. The square coordination of the Au atom in complex II is slightly distorted: the Au-Cl bond lengths are 2.266(2)–2.277(2) ?, the ClAuCl bond angles are equal to 89.7(1)°–90.5(1)°, the root-mean-square deviation of the atoms from the coordination plane being 0.004 ?. Original Russian Text ? V.V. Sharutin, V.S. Senchurin, O.A. Fastovets, A.P. Pakusina, O.K. Sharutina, 2008, published in Koordinatsionnaya Khimiya, 2008, Vol. 34, No. 5, pp. 373–379.  相似文献   

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DFT (B3LYP functional) and MP2 methods using 6-311+G(2d,2p) basis set have been employed to examine the effect of ring fusion to benzene on the cation--π interactions involving alkali metal ions (Li+, Na+, and K+) and alkaline earth metal ions (Be2+, Mg2+ and Ca2+). Our present study indicates that modification of benzene (π-electron source) by fusion of monocyclic or bicyclic (or mixture of these two kinds of rings) strengthens the binding affinity of both alkali and alkaline earth metal cations. The strength of interaction decreases in the following order: Be2+ > Mg2+ > Ca2+ > Li+ > Na+ > K+ for any considered aromatic ligand. The interaction energies for the complexes formed by divalent cations are 4–6 times larger than those for the complexes involving monovalent cations. The structural changes in the ring wherein metal ion binds are examined. The distance between ring centroid and the metal ion is calculated for all of the complexes. Strained bicyclo[2.1.1]hexene ring fusion has substantially larger effect on the strength of cation--π interactions than the monocyclic ring fusion for all of the cations due to the π-electron localization at the central benzene ring.  相似文献   

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张彩云  武海顺 《化学学报》2005,63(11):979-984
用DFT的B3LYP方法在6-31G(d)基组的水平上, 对闭式多面体簇合物(HAlNH)12及其内含式X@(HAlNH)12和外接式X(HAlNH)12 (X=F, Cl, Br, O2-, S2-, Se2-)复合物的结构进行了构型优化和能量计算, 并讨论了几何构型、自然键轨道(NBO)、振动频率、能量参数及NMR数据与结构的关系, 最后得到复合物结构的稳定性信息, 具有Th对称性的X@(HAlNH)12 (X=F, Cl, Br, S2-, Se2-)复合物和具有C3对称性的O2-@(HAlNH)12复合物为内含式的基态结构, 从能量角度分析, 内含式复合物比外接式复合物的结构稳定.  相似文献   

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用DFT的B3LYP方法在6-31G(d)基组的水平上, 对闭式多面体簇合物(HAlNH)12及其内含式X@(HAlNH)12和外接式X(HAlNH)12 (X=F, Cl, Br, O2-, S2-, Se2-)复合物的结构进行了构型优化和能量计算, 并讨论了几何构型、自然键轨道(NBO)、振动频率、能量参数及NMR数据与结构的关系, 最后得到复合物结构的稳定性信息, 具有Th对称性的X@(HAlNH)12 (X=F, Cl, Br, S2-, Se2-)复合物和具有C3对称性的O2-@(HAlNH)12复合物为内含式的基态结构, 从能量角度分析, 内含式复合物比外接式复合物的结构稳定.  相似文献   

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