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  • 1975-1979  (4)
  • 1970-1974  (4)
  • 1
    Electronic Resource
    Electronic Resource
    The Hartree-Fock theory of local regions in molecules (1978)
    s.l. : American Chemical Society
    Journal of the American Chemical Society 100 (1978), S. 7742-7743 
    Details
    ISSN: 1520-5126
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/ja00492a058
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  • 2
    Electronic Resource
    Electronic Resource
    Positron lifetimes and annihilation lineshape in Cd and au from 4.2 K to the melting points (1977)
    Springer
    Applied physics 12 (1977), S. 59-67 
    Details
    ISSN: 1432-0630
    Keywords: 61.70 ; 81
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract By means of an integrated source-specimen technique the temperature dependence of positron lifetimes and annihilation lineshapes has been measured, on the same specimens of gold and cadmium from 4.2K to the melting points, and also in electronirradiated and quenched gold. The anomalous temperature dependence of positron annihilation at intermediate temperatures (200 to 350 K in Cd, 270 to 750 K in Au) discovered by Lichtenberger, Schulte, and MacKenzie is confirmed. The data are incompatible with the idea that the intermediate temperature dependence is due to thermal expansion. They are well explained by an extension of the trapping model which includes the formation of metastable self-trapped positrons. From lineshape measurements after electron irradiation at 180 K and after quenching it is deduced that the trapping rate of positrons at vacancy-type defects in Au is temperature independent below room temperature.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00900069
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  • 3
    Electronic Resource
    Electronic Resource
    Hartree-Fock calculation of cohesive energies and equilibrium lattice constants for solid Li and Be (1975)
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 9 (1975), S. 775-787 
    Details
    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 described for calculating cohesive energies of solids in the single-determinant approximation including the full Hartree-Fock exchange. The method involves (1) the construction of a rapidly convergent series in vectors of the direct and reciprocal lattice for the Fock matrix, (2) a decoupling procedure for the k-dependence of the Fock matrix, which works even in the case of strong interatomic overlap. An application to Li and Be is given. Agreement with experiment to 10% is achieved for the cohesive energies and to 5% for the equilibrium lattice constants.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/qua.560090503
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  • 4
    Electronic Resource
    Electronic Resource
    Schwingungsspektren und Kraftkonstanten der Übergangsreihen OPF3—OP(OCH3)3 und SPF3—SP(OCH3)3Professor Günther Rienäcker zum 70. Geburtstage am 13. Mai 1974 gewidmet (1974)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 405 (1974), S. 275-285 
    Details
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Vibrational Spectra and Force Constants of the Series OPF3—OP(OCH3)3 and SPF3—SP(OCH3)3The vibrational spectra (IR and RAMAN) for OPF2(OCH3), OPF(OCH3)2, SPF2(OCH3) and SPF(OCH3)2 are reported and assigned to the normal vibrations. The valence force constants are calculated by a simplified valence force field. The changes of the bonds are discussed.
    Notes: Es werden die Schwingungsspektren (IR und RAMAN) von OPF2(OCH3), OPF(OCH3)2, SPF2(OCH3) und SPF(OCH3)2 mitgeteilt und die Zuordnung zu den Grundschwingungen vorgenommen. Nach einem Näherungsverfahren werden die Valenzkraftkonstanten berechnet und die Bindungsverhältnisse diskutiert.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19744050308
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  • 5
    Electronic Resource
    Electronic Resource
    Darstellung und Schwingungsspektrum von Tetrathiomethyl-phosphonium-hexachloroantimonatFrau Professor Margot Becke-Goehring zum 60. Geburtstage gewidmet (1974)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 406 (1974), S. 307-311 
    Details
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Preparation and Vibrational Spectrum of Tetra-thiomethyl-phosphoniuin-hexachloroantimonatePreparation, properties and vibrational spectrum of Tetra-thiomethyl-phosphonium-hexachloroantimonate are reported. The kind of bonding in the ion is brief discussed.
    Notes: Es wird über die Darstellung, Eigenschaften und Schwingungsspektren des Tetra-thiomethyl-phosphonium-hexachloroantimonats berichtet. Die Bindungsverhältnisse werden kurz diskutiert.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19744060225
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  • 6
    Electronic Resource
    Electronic Resource
    Über das Fluoreszenzthermochrome Acetonitrilo-Kupferjodid mit Dibenzo-18-Krone-6 (1978)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 442 (1978), S. 221-224 
    Details
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: About the Fluorescence Thermochromism of Acetonitrile Copper Iodide with Dibenzo-18-Crown-6Copper iodide reacts in actonitrile solution with dibenzo-18-crown-6 to form a compound,(CuJ)4(CH3CN)4(db-18-c-6), which fluoresces yellow at 298K, but pink at 77 K. It decomposes at 55.3°C. (5 Torr) by lost of acetonitrile and a heterogeneous mixture of copper iodide and polyether results. In absence of dibenzo-18-crown-6, copper iodide forms with acetonitrile a heterogeneous mixture of copper iodide and polyether results. In absence of dibenzo-18-crown-6, copper iodide forms with acetonitrile a solvate CuJ. CH3CN. It also shows fluorescence thermochromism (yellow at 298 K, but green at 77 k) but decomposes at 0°C and 760 Torr.The luminescences pectra of the macrocyclic polyether complex at 298 K is redshifted. This probably results from intersection between the crown and the acetonitrile copper iodide.
    Notes: Kupferjodid bildet in Acetonitril mit Dibenzo-18-Krone-6 eine Verbindung der Zusammensetzung (CuJ)4(CH3CN)4(db-18-c-6), die bei Raumtemperatur gelb, bei 77K rosa fluoresziert. Sie zersetzt sich bei 55,3°C (5 Torr) unter Verlust von Acetonitril zu einem heterogenen Gemenge aus Kronenäther Kupferjodid.In Abwesenheit von Kronenäther bildet Kupferjodid in Acetonitril ein Solvat CuJ · CH3CN. Es ist ebenfalls fluoreszenzthermochrom (gelb bei 298 K, grün bei 77 K) und zersetzt sich allerdings schon bei 0°C( 760 Torr). Das Lumineszenzspektrum des makrocyclischen Polyätherkomplexes ist bei 298 K rotverschoben, was wahrscheinlich auf die Wechselwirkung des Kronenäthers mit dem Acetonitrilo-Kupferjodid zurückzuführen ist.
    Additional Material: 3 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19784420129
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  • 7
    Electronic Resource
    Electronic Resource
    Schwingungsspektren und Kraftkonstanten der Übergangsreihen OP(N(CH3)2)3-OPCI3 und SP(N(CH3)2)3-SPCl3Professor Oskar Glemser zum 60. Geburtstage gewidmet (1971)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 385 (1971), S. 56-64 
    Details
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The vibrational spectra (IR and RAMAN) from XP(N(CH3)2)2Cl and XP(N(CH3)2)Cl2 (X = O, S) are reported. The spectra are discussed and assigned to the normal vibrations in connection with the spectra of XP(N(CH3)2)3 and XPCl3. The valence force constants are calculated by a simplified valence force field. f P-NR2 and f P-Cl decrease slightly on substitution of the NR2 group by chlorine; f P-X, on the contrary, increases very distinctly. This is caused by the change from an element of the second period to an element of the third one.
    Notes: Es werden die Schwingungsspektren (IR und RAMAN) von XP(N(CH3)2)2Cl und XP(N(CH3)2)Cl2 mitgeteilt und in Zusammenhang mit den Spektren der Randglieder dieser Reihe XP(N(CH3)2)3 und XPCl3 (X = O, S) diskutiert und zugeordnet. Auf dieser Grundlage wurden nach einem Näherungsverfahren die Valenzkraftkonstanten ermittelt. Während f P-NR2 und f P-Cl beim Ersatz der NR2-Gruppen durch Chlor leicht abnehmen. zeigen beide f P-X eine starke Zunahme. Da beide Bindungspartner (NR2 und Cl) ungefähr gleiche Elektronegativität besitzen, so muß die starke Zunahme von f P-X auf die Zugehörigkeit der beiden Bindungspartner zu verschiedenen Perioden des Systems zurückgeführt werden.
    Additional Material: 5 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19713850109
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  • 8
    Electronic Resource
    Electronic Resource
    Schwingungsspektren und Kraftkonstanten der Übergangsreihen OPF3 - OP(CH3)3 und SPF3 - SP(CH3)3 (1972)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 389 (1972), S. 269-279 
    Details
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The vibration spectra (IR and RAMAN) are reported for OPF2(CH3), OPF(CH3)2, SPF2(CH3), SPF(CH3)2 and SPF2(C2H5) and assigned to the normal vibrations. For these compounds all valence force constants are calculated by a simplified valence force field. Substitution of fluorine atoms by the methyl group causes a diminuation of all force constants. There is a clear difference between Δf P—CH3 (- 18%) and Δf X =P and Δf P—F (-30%). The P—CH3 bond is incapable to form dπ—pπ-bonds. Therefore the diminuation of f P—CH3 is caused only by the inductive effect.
    Notes: Von OPF2(CH3), OPF(CH3)2, SPF2(CH3), SPF(CH3)2 und SPF2(C2H5) werden die Schwingungsspektren (meistens IR und RAMAN) mitgeteilt und den Grundschwingungen zugeordnet. Gemeinsam mit den Endgliedern XPF3 und XP(CH3)3 (X = O, S) werden die Valenzkraftkonstanten nach einem Näherungsverfahren berechnet. Sämtliche Kraftkonstanten nehmen beim Ersatz von Fluor durch die Methylgruppe stark ab. Für f P—CH3 (-18%) ergibt sich gegenüber f P = X und f P—F (-30%) ein deutlicher Unterschied, bedingt durch die Unfähigkeit der CH3-Gruppe zur Ausbildung von dπ—pπ-Bindungen. Die Abnahme für f P—CH3 wird auf den induktiven Effekt allein zurückgeführt.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19723890307
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