Library

You have 0 saved results.
Mark results and click the "Add To Watchlist" link in order to add them to this list.
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Theoretical chemistry accounts 86 (1993), S. 429-437 
    ISSN: 1432-2234
    Keywords: Spin density ; Hyperfine coupling constants ; Influence of excitation classes ; Indirect and direct contributions toA iso
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Summary Reliable prediction of the isotropic hyperfine coupling constantA iso is still a difficult task forab initio calculations. Strong dependence on the method employed for its calculation has been found. Within a CI ansatzA iso is considerably affected by the excitation classes taken into account within the CI calculation. In the present work the influence of various excitation classes onA iso is examined. Calculations including all single, double, triple and a large part of the quadruple excitations are performed and the individual effects of the excitation classes are studied. It is found that the surprisingly good agreement found for S-CI treatments is due to large error cancellations. The importance of higher than double excitations arises from their indirect influence on the single excitations.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 621 (1995), S. 2065-2069 
    ISSN: 0044-2313
    Keywords: Tetraphosphorus hexaoxide monoselenide ; preparation ; crystal structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis, Crystal Structure, and Spectroscopic Characterization of Tetraphosphorus Hexaoxide Monoselenide, P4O6SeP4O6Se has been synthesized by photochemical reaction between P4O6 and elemental selenium in CS2 in presence of iodine as a catalyst. Single crystals form at purification via sublimation. The compound (m. p. 46°C) crystallizes in the monoclinic space group P21/c (no. 14) with a = 1 051.8(2), b = 652.9(1), c = 1 178.6(2) pm, β = 109.29(1)°, Z = 4. Within the limits of experimental error, the molecules exhibit C3v symmetry. IR, Raman, and 31P n.m.r. (solution) spectra of the compound are reported and discussed. The geometry of the Molecule as determined by theoretical methods (SCF level) is in good agreement with the experimental results.
    Notes: P4O6Se wurde durch photochemische Reaktion von P4O6 mit elementarem Selen in CS2 in Gegenwart von Iod als Katalysator dargestellt; Einkristalle entstanden bei der Reinigung durch Sublimation. Die Verbindung (Fp. 46°C) kristallisiert in der monoklinen Raumgruppe P21/c (Nr. 14) mit a = 1 051,8(2), b = 652,9(1), c = 1 178,6(2) pm, β = 109,29(1)°, Z = 4. Im Rahmen der Fehlergrenzen der Strukturbestimmung besitzen die Moleküle C3v-Symmetrie. IR-, Raman- und 31P-Lösungs-NMR-Spektren der Verbindung werden mitgeteilt und diskutiert. Die mit quantenchemischen Methoden auf SCF-Niveau berechnete Molekülgeometrie stimmt mit der experimentell bestimmten gut überein.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...