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  • Inorganic Chemistry  (12)
  • Computational Chemistry and Molecular Modeling  (3)
  • 42.75
  • 1970-1974  (15)
  • 1
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 107 (1974), S. 1891-1902 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Preparation of [2.2]Paracyclophanes by Addition of Acetylene Derivatives to 1,2,4,5-HexatetraeneThe tetrasubstituted [2.2]paracyclophanes 4a - e are formed by cycloaddition of the symmetrical acetylene derivatives 2a - e to 1,2,4,5-hexatetraene (1), and their constitution and configuration is established by spectroscopic methods, degradation and pyrolysis experiments. The tetramethyl ester 4a is reduced to the tetraalcohol 4g, and the tetracarboxylic acid 4c is converted to the bisanhydride 4f and [2.2] paracyclophanes (4h), respectively. All possible disubstituted [2.2] paracyclophanes 6 are obtained when methyl propiolate (5a) is added to. 1, whereas further symmetrical and unsymmetrical acetylene derivatives do not react with 1.
    Notes: Die tetrasubstituierten [2.2]Paracyclophane 4a - e werden durch Cycloaddition der symmetrischen Acetylenderivate 2a - e an 1,2,4,5-Hexatetraen (1) dargestellt und ihre Konstitution und Konfiguration durch spektroskopische Methoden. Abbau- und Pyrolyseversuche bewiesen. Der Tetramethylester 4a wird zum Tetraalkohol 4g reduziert und die Tetracarbonsäure 4c in das Bisanhydrid 4f bzw. [2.2] Paracyclophan (4h) übergeführt. Bei der Anlagerung von Propiolsäure-methylester (5a) an 1 werden alle isomeren disubstituierten [2.2]paracyclophanes 6 erhalten. Weitere symmetrische und unsymmetrische Acetylenderivate reagieren nicht mit 1.
    Additional Material: 3 Tab.
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  • 2
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Berichte der deutschen chemischen Gesellschaft 106 (1973), S. 3461-3462 
    ISSN: 0009-2940
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 8 (1974), S. 179-191 
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A method is given for obtaining the common molecular integrals over generalized gaussian functions: \documentclass{article}\pagestyle{empty}\begin{document}$$ \chi_i = x^{\lambda_i}_i \exp \big\{ - \big(\alpha_i x^2_i + \alpha^{\prime}_i x^{\prime 2}_i + \alpha^{\prime\prime}_i x^{\prime\prime 2}_i\big)\big\} $$\end{document}The present algorithms are expected to be more efficient than those given in earlier work by the same author.
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  • 4
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 6 (1972), S. 859-880 
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: An outline is given of a semi-empirical scheme for molecular-orbital calculations on transition-metal complexes according to a revised INDO procedure. To judge the reliability of the results of the calculations, the charge-transfer transitions of a number of complexes have been calculated and compared with experimental data. Both for the excitation energies and for the oscillator strengths the agreement is very satisfactory. With respect to the sequence of occupied metal and ligand orbitals it was found that for closed-shell d6 and d8 systems the molecular orbitals which are mainly composed of metal d orbitals have a lower energy than the orbitals built up from ligand p orbitals. Calculations by the extended Hückel method and other similar schemes give the d orbitals as the highest occupied ones as a result of a bad approximation of the diagonal elements of the Fock matrix. The consequences for the interpretation of photo-electron spectra of transition-metal complexes are discussed.
    Additional Material: 3 Ill.
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  • 5
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 7 (1973), S. 133-134 
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
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  • 6
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Contributions to the Chemistry of Phosphorus. 53. 1,2,3,4-Tetraphenylcyclo-5-thia-1,2,3,4-tetraphosphane1,2,3,4-Tetraphenyl-cyclo-5-thia-1,2,3,4-tetraphosphane (“tetraphenylcyclotetraphosphine-monosulphide„) 1 is obtained in very good yield and purity by the reaction of pentaphenyl-cyclopentaphosphane (2) with sulphur (4 C6H5P: 1 S). Further new methods of preparation are the comproportionation of 2 with (C6H5PS)3, and the reaction of dipotassium-triphenyl-cyclotriphosphide (4) with sulphur dichloride. The IR and 31P-NMR spectra of the title compound indicate unambiguously the heterocyclophosphane structure 1 with a five-membered P4S ring. The elevated stability of this ring system is evident from numerous other formation reactions, which are reported in addition.
    Notes: 1,2,3,4-Tetraphenyl-cyclo-5-thia-1,2,3,4-tetraphoshan (“Tetraphenyl-cyclotetraphosphin-monosulfid”) 1 wird durch Umsetzung von Pentaphenyl-cyclopentaphosphan (2) mit Schwefel (4 C6H5P:1 S) in sehr guter Ausbeute und Reinheit erhalten. Weitere neue Darstellungswege sind die Komproportionierung von 2 und (C6H5PS)3 sowie die Reaktion von Dikalium-triphenyl-cyclotriphosphid (4) mit Schwefeldichlorid. Das IR- und das 31P-NMR-Spektrum der Verbindung sind ein eindeutiges Indiz für die Heterocyclophosphan-Struktur 1 mit fünfgliedrigem P4S-Ring. Die besondere Stabilität dieses Molekelgerüstes geht aus der größeren Zahl weiterer Bildungs-Reaktionen für 1 hervor, über die außerdem berichtet wird.
    Additional Material: 2 Ill.
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  • 7
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 380 (1971), S. 37-40 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Borates of the compositions formulated above are prepared in crystalline form by cooling their molten solutions in the corresponding borate M2+O · xB2O3. Some properties of the compounds are reported.
    Notes: Die Borate M2+Sn(BO3)2 (M = Mg, Ca, Sr, Ba, Cd, Mn, Co), M2+Zr · (BO3)2 (M = Ca, Sr, Ba, Cd) und BaTi(BO3)2 werden durch Abkühlen einer schmelzflüssigen Lösung in einem Überschuß des jeweiligen Borates M2+O · xB2O3 in kristalliner Form dargestellt. Einige Eigenschaften der Verbindungen werden mitgeteilt.
    Additional Material: 2 Tab.
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  • 8
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 386 (1971), S. 288-296 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Transition metal manganates with spinel structure are prepared by joint decomposition of MnSO4 and MeSO4 (Me = Co, Zn, Cu, Ni) about 1000°C in the fused sodium potassium sulfate eutectic. Complete series of mixed oxides MexMn3-xO4+γ have been observed within the limits: Co: 0 〈 x 〈 3; Zn: 0 〈 x 〈 1,5; Cu: 0 〈 x 〈 1; Ni: 0 〈 x 〈 1. The compounds Co2.2Mn0.8O4 to Co1.9Mn1.1O4, ZnMn2O4, Zn1.25Mn1.75O4 may be prepared in high yield and as single-phase compounds. The oxygen deficit of the manganates has the limits 0,02 〉 γ 〉 -0.08. The lattice constants of the spinels are compared with literature dates.
    Notes: Durch gemeinsame Zersetzung von MnSO4 und MeSO4 (Me = Co, Zn, Cu, Ni) in der eutektischen K—Na-Sulfat-Schmelze bei Temperaturen um 1000°C sind grobkristalline Übergangsmetall-Manganate darstellbar. Dabei wurden lückenlose Reihen im Spinellgitter kristallisierender Mischoxide MexMn3-xO4+γ in folgenden Grenzen erhalten: Co: 0 〈 x 〈 3; Zn: 0 〈 x 〈 1,5; Cu: 0 〈 x 〈 1; Ni: 0 〈 x 〈 1. Folgende Verbindungen lassen sich mit definierter Zusammensetzung in guter Ausbeute darstellen: Co2,2Mn0,8O4 bis Co1,9Mn1,1O4, ZnMn2O4 und Zn1,25Mn1,75O4. Das Sauerstoffdefizit der Manganate lag zwischen 0,02 〉 γ 〉 -0,08. Die Gitterkonstanten der Spinelle werden mit Literaturangaben verglichen.
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  • 9
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Spinels with substituted Nonmetal Sublattices. IV. CuCr2(S1-xSex)4 and CuCr2(Se1-xTex)4Polycrystalline samples of the spinel system CuCr2(S1-xSex)4 have been prepared with 0 ≤ x ≤ 1. We found that in the spinel system CuCr2(Se1-xTex)4 no solid solution is existent in the range 0.01 ≤ x ≤ 0.70. When S is substituted by Se and Se by Te the lattice constants increase linearely by 0.52 Å and 0.81 Å respectively. The anion-sublattice shows random distribution of the chalcogen atoms, the chalcogen parameters u are constant in the system CuCr2(S1-xSex)4 with a mean value of u = 0.3829. The calculated anion-cation-distances lead to a covalent tetrahedral radius rCu = 1.23 Å. This radius is in agreement with the radius rCu = 1.22 Å of Cu spinels with Cu in the valence +1.
    Notes: Im Spinellsystem CuCr2(S1-xSex)4 erfolgt im Bereich 0 ≤ x ≤ 1 lückenlose Mischkristallbildung, während beim Spinellsystem CuCr2(Se1-xTex)4 in diesem Bereich zwischen 0,01 ≤ x ≤ 0,70 eine Mischungslücke auftritt. Beim Ersatz von S durch Se wächst die Gitterkonstante a linear um 0,52 Å, beim Ersatz von Se durch Te linear um 0,81 Å. Das Anionenteilgitter ist statistisch mit Chalkogenatomen besetzt. Die Chalkogenparameter im System CuCr2(S1-xSex)4 sind konstant, der Mittelwert beträgt u = 0,3829. Aus den berechneten Anionen-Kationen-Abständen erhält man einen kovalenten Tetraederradius rCu = 1,23 Å. Dieser Radius stimmt mit dem Radius rCu = 1,22 Å überein, den man aus Cu-Spinellen mit Cu in der Oxydationsstufe +1 erhält.
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  • 10
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 397 (1973), S. 31-39 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Hexakis(trifluorophosphine) Complexes of Chromium(0), Molybdenum(0), and Tungsten(0)The reaction of tris(π-allyl)chromium with PF3 at low pressure yields deep darkgreen tris(π-allyl)-trifluorophosphine chromium which is slowly converted into hexakis(trifluorophosphine) chromium: If tris(π-allyl)chromium is reacted with PF3 at high pressure, the only isolable product is Cr(PF3)6. Anhydrous molybdenum(V) and tungsten(VI) chloride react with PF3 in the presence of copper to the hexakis(trifluorophosphine) complexes of the zerovalent metals: The hexakis(trifluorophosphine) complexes are thermally very stable, crystalline, colourless solids.
    Notes: Eine ätherische Lösung von Tris(π-allyl)-chrom setzt sich unter geringem Trifluorphosphindruck zu tief dunkelgrünem Tris(π-allyl)-trifluorphosphinchrom um, das langsam zu kristallinem, farblosen Hexakis(trifluorphosphin)-chrom(0) weiterreagiert: Bei den Hochdruckumsetzungen des kristallinen Tris(π-allyl)-chrom konnte nur das Endprodukt Cr(PF3)6 isoliert werden. Wasserfreies Molybdän(V)-chlorid und Wolfram(VI)-chlorid bilden in Gegenwart von Kupfer als halogenbindendem Beimetall unter Trifluorphosphindruck die ebenfalls kristallinen, farblosen Hexakis(trifluorphosphin)-metall(0)-Komplexe: .
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