Search Results - (Author, Cooperation:C. Pietzsch)

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  1. 1
    Staff View
    Publication Date:
    2016-04-30
    Publisher:
    American Association for the Advancement of Science (AAAS)
    Print ISSN:
    0036-8075
    Electronic ISSN:
    1095-9203
    Topics:
    Biology
    Chemistry and Pharmacology
    Computer Science
    Medicine
    Natural Sciences in General
    Physics
    Published by:
    http://www.aaas.org/

    Latest Papers from Table of Contents or Articles in Press
  2. 2
    Jacob, K. ; Pietzsch, C.
    Springer
    Published 1997
    Staff View
    ISSN:
    1434-4475
    Keywords:
    Vanadium ; Thallium ; Heterobimetallic ; 2-(Dimethylaminomethyl)ferrocenyl ; Orthometallation ; Electron transfer ; Möβbauer spectroscopy
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Chemistry and Pharmacology
    Description / Table of Contents:
    Summary Syntheses and properties of 2-(dimethylaminomethyl)ferrocenylderivatives of the composition (FcN) n VCl3−n (FcN=2-(dimethylaminomethyl)ferrocenyl;n=1 (1), 2 (2), 3 (3)), which are formed from VCl3·3THF and (FcN) Li (I), are reported. WhereasCp 2VCl2 (Cp=C5H5) reacts withI under formation ofCp 2V(FcN) (4), VO(acac)2 (acac=anion of acetylacetonate, C5H7O2) can be transformed into the 2-(dimethylaminomethyl)-ferrocenyl compound of tetravalent vanadium (FcN)VO(acac),5). However, when VOCl2·2THF reacts withI, the organovanadium(III)-derivative Li[(FcN)2V(O)Cl] (6) is formed. Reactions of VCl4·2THF,Cp 2VCl2, VOCl3, andCpVOCl2 with (FcN)3Tl (II) lead to thermally instable vanadiumorganic compounds under formation of (FcN)2TlCl (7). A detailed characterization of1–7 was carried out by elementary analysis, determination of effective magnetic moments, IR, mass and1H NMR spectroscopy as well as — especially referring to the formation of possible chelate structures — by UV/Vis andMöβbauer spectroscopy.
    Notes:
    Zusammenfassung Synthesen und Eigenschaften von 2-(Dimethylaminomethyl)ferrocenyl-Derivaten der Formel (FcN) n VCl3−n (FcN=2-(Dimethylaminomethyl)ferrocenyl;n=1 (1), 2 (2), 3 (3)), die aus VCl3·3THF und (FcN) Li (I) entstehen, werden mitgeteilt. WährendCp 2VCl2 (Cp=C5H5) mitI unter Bildung vonCp 2 V(FcN) (4) reagiert, läßt sich VO (acac)2 (acac=Anion des Acetylacetonates, C5H7O2) in die 2-(Dimethylaminomethyl)ferrocenyl-Verbindung des vierwertigen Vanadiums (FcN)VO(acac),5) überführen. Dagegen entsteht bei Umsetzungen von VOCl2·2THF mitI das Organovanadium (III)-Derivat Li [(FcN)2V(O)Cl] (6). Reaktionen von VCl4·2THF,Cp 2VCl2, VOCl3 undCpVOCl2 mit (FcN)3Tl (II) führen unter Bildung von (FcN)2TlCl (7) zu thermisch instabilen vanadiumorganischen Verbindungen. Eine eingehende Charakterisierung von1–7 erfolgte durch Elementaranalysen, Ermittlung der effektiven magnetischen Momente, IR-, Massen- und NMR-Spektroskopie sowie, insbesondere hinsichtlich der Ausbildung möglicher Chelatstrukturen, durch UV/Vis und Mößbauer-Spektroskopie.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1007/BF00810770

    Articles: DFG German National Licenses
  3. 3
    Jacob, K. ; Edelmann, F. T. ; Pietzsch, C.
    Springer
    Published 1997
    Staff View
    ISSN:
    1434-4475
    Keywords:
    Organolanthanides ; Heterobimetallic complexes ; Ferrocene ; Mößbauer spectroscopy
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Chemistry and Pharmacology
    Notes:
    Summary Reactions of 2-(dimethylaminomethyl)ferrocenyl-lithium ((FcN)Li,1) with various cerium(IV) precursors lead to the formation of heterobimetallic organocerium(III) complexes. The compounds Li3[(FcN)2CeF4(THF)3] (2), (FcN)2CeF(DME)2 (3), Li4[(FcN)CeCl6] (4), and Li[(FcN)CeCl3(DME)] (5) have been isolated by redox reactions. Similar treatment of (C5Me5)2 Ce(μ-Cl)2K(THF)2 with one equivalent of1 affords the neutral species (C5Me5)Ce(FcN)Cl (6)via displacement of one C5Me5 ligand. Complexes of the type (C5Me5)Ln(FcN)Cl have also been isolated forLn=Pr (7), Nd (8), and Sm (9). These and related heterobimetallic lanthanideFcN complexes have been studied by Mößbauer spectroscopy.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1007/BF00807305

    Articles: DFG German National Licenses
  4. 4
    Staff View
    ISSN:
    0040-6031
    Keywords:
    Bronze ; DSC ; DTA ; DTG ; Degradation ; ESRS ; IRS ; KEGGIN ; Moessbauer ; Polyoxometallate ; TG ; XRPD
    Source:
    Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics:
    Chemistry and Pharmacology
    Type of Medium:
    Electronic Resource
    URL:
    http://linkinghub.elsevier.com/retrieve/pii/0040-6031(94)80210-6

    Articles: DFG German National Licenses
  5. 5
    Kirsten, A. ; Pietzsch, C. ; Oettel, H.
    Springer
    Published 1998
    Staff View
    ISSN:
    1432-1130
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Chemistry and Pharmacology
    Notes:
    Abstract Reactive magnetron sputtered layers of nitridic hard coatings (e.g. TiN) often show high intrinsic stresses caused by the differences of the thermal expansion coefficients of the layer and the substrate and the incorporation of atoms of sputtering and/or reactive gas atoms in lattice voids. The decrease of hardness and stresses of such layers after heat treatment seems to originate from the out-diffusion of interstitial excess reactive gas atoms (e.g. nitrogen). In this study 57Fe Mössbauer spectroscopy on (Ti, Fe)N model layers is used to obtain direct information about the mechanism of the development and variation of intrinsic stresses in nitridic hard coatings in connection with point defects (e.g. excess N). The results of this investigations are supported by X-ray analysis and Glow Discharge Optical Spectroscopy (GDOS).
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1007/s002160050980

    Articles: DFG German National Licenses
  6. 6
    Pietzsch, C. ; Schmidt, L.
    Springer
    Published 1990
    Staff View
    ISSN:
    1588-2780
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Chemistry and Pharmacology
    Energy, Environment Protection, Nuclear Power Engineering
    Notes:
    Abstract For the first time Mössbauer data of geochemically completely characterized and genetically exactly classified dioctahedral 2M1 micas from the pegmatitic district Alto Ligonha /Northern Mozambique/ are given. The results of the iron distribution allow to draw qualitative conclusions concerning the redox potential during the formation of the deposit.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1007/BF02328767

    Articles: DFG German National Licenses
  7. 7
    Pietzsch, C. ; Cheprasov, D. P.
    Springer
    Published 1991
    Staff View
    ISSN:
    1588-2780
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Chemistry and Pharmacology
    Energy, Environment Protection, Nuclear Power Engineering
    Notes:
    Abstract Results of phase generation and carbide formation after a shock wave treatment of the C80W2 steel are reported. It is shown that the reactions follow the energy supply to the steel by shock wave treatment.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1007/BF02165894

    Articles: DFG German National Licenses
  8. 8
    Pietzsch, C. ; Wartenberger, R.
    Springer
    Published 1990
    Staff View
    ISSN:
    1588-2780
    Source:
    Springer Online Journal Archives 1860-2000
    Topics:
    Chemistry and Pharmacology
    Energy, Environment Protection, Nuclear Power Engineering
    Notes:
    Abstract In machine drawn weldor safety glasses with a different protection grade and a total iron oxide content of 6.8–9.5% the lattice coordination of iron and the Fe2+/Fetot ratio were determined by Mössbauer spectroscopy. In combination with electron beam microanalysis and specific sample preparation, homogeneity disturbances were observed inside the defect glass as well as on its surface.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1007/BF02328768

    Articles: DFG German National Licenses
  9. 9
    Weiner, H. ; Lunk, H.-J. ; Fuchs, J. ; Ziemer, B. ; Stösser, R. ; Pietzsch, C. ; Reich, P.

    Weinheim : Wiley-Blackwell
    Published 1991
    Staff View
    ISSN:
    0044-2313
    Keywords:
    Dibarium-α-dodecawolframatoferrate(III)-26-hydrate ; synthesis ; crystal structure ; Chemistry ; Inorganic Chemistry
    Source:
    Wiley InterScience Backfile Collection 1832-2000
    Topics:
    Chemistry and Pharmacology
    Description / Table of Contents:
    Synthesis and Structure Studies of Ba2H[α-FeO4W12O36] · 26 H2OThe heteropolyanion compound Ba2H[α-FeO4W12O36] · 26 H2O (I) crystallizes in the tetragonal space group P4n2 with the lattice parameters a = 12.398(6), c = 18.721(6) Å; Z = 2; Dx = 4.128 g · cm-3. The structure was solved on a twinned crystal from 1029 observed reflections and refined to an index R of 7.6%. The calculations were done by means of a modified ORFLS-programme by Eitel and Bärnighausen. The heteropolyanion [α-FeO4W12O36]5- has the well known α-Keggin structure. The average distance of the four central oxygen atoms to the FeIII position (0, 0, 0) is 1.84 Å. The angles ∢ O—Fe—O are 112.3° (4X) and 103.9 (2X), respectively, which leads to an disphenoidal distortion of the FeO4 tetrahedron.The powder and single crystal ESR spectra of I show the anisotropy of the FeIII fine structure transition 1/2 ↔ -1/2. The Mößbauer spectra confirm the tetragonal distortion of the central FeO4 tetrahedron (quadrupole splitting Δ ≈ 0.50 mm · s-1).
    Notes:
    Die erstmalig in einkristalliner Form dargestellte Heteropolyanionenverbindung Dibarium-α-dodekawolframatoferrat(III)-26-Hydrat, Ba2H[α-FeO4W12O36] · 26 H2O (I), kristallisiert tetragonal mit den Gitterkonstanten a = 12,398(6), c = 18,721(6) Å; Z = 2; Dx = 4,128 g α cm-3. Für den vorliegenden Inversionszwilling mit einem Heteropolyanion vom α-Keggin-Typ wurde zur Verfeinerung der Kristallstruktur in der Raumgruppe P4n2 ein von Eitel und Bärnighausen modifiziertes ORFLS-Programm benutzt (R-Wert 7,6%). Der mittlere Abstand der vier zentralen Sauerstoffatome zur FeIII-Position (0, 0, 0) beträgt 1,84 Å. Die Winkel ∢ O—Fe—O weichen mit 112,3(4X) bzw. 103,9°(2X) deutlich von 109,5° ab, wodurch das Tetraeder zu einem tetragonalen Disphenoid verzerrt wird.Die Mößbauer-Spektren von I weisen eine deutliche Quadrupolaufspaltung von Δ; ≈ 0,50 mm · s-1 auf, die durch die Asymmetrie in der Umgebung von FeIII hervorgerufen wird. Damit in Übereinstimmung zeigen die EPR-Spektren sowohl für Pulver als auch für einen Einkristall von I ein Signal bei g ≃ 2, das im wesentlichen aus dem Feinstrukturübergang 1/2 ↔ - 1/2 des FeIII-Ions herrührt und eine deutliche Anisotropie aufweist.
    Additional Material:
    5 Ill.
    Type of Medium:
    Electronic Resource
    URL:
    http://dx.doi.org/10.1002/zaac.19915940122

    Articles: DFG German National Licenses