Library

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
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 62 (1997), S. 557-570 
    ISSN: 0020-7608
    Keywords: Chemistry ; Theoretical, Physical and Computational Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The calculation of molecular integrals is extremely important for applications to such diverse areas as statistical mechanics and quantum chemistry. A careful derivation of a method for calculating primitive Gaussian integrals originally proposed by Obara and Saika is presented. The basic recursion relations for the two- and three-center overlap integrals is derived using a simple technique. Several new horizontal recursion relations are given. Finally, an innovative method for implementing these recursion relations is discussed. The recursion relations in this form are suited for programming using a symbolic manipulation language. There are several reasons why it is of interest to consider programming with symbolic manipulation. It has been found that it is possible to write algorithms that will generate values for Gaussian integrals for very large values of angular momentum automatically. Calculations can be done to arbitrary precision in Maple. Having these recursions programmed in Maple allows for the possibility of using the Maple programs to help in the writing of similar programs in other languages which are, numerically, much faster. © 1997 John Wiley & Sons, Inc. Int J Quant Chem 62: 557-570, 1997
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 63 (1997), S. 601-614 
    ISSN: 0020-7608
    Keywords: Chemistry ; Theoretical, Physical and Computational Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: We analyze the divergent contributions to the Hamiltonian for extended, nonmetallic systems in one dimension, to both the ground-state correlation energy and to the correlated band structure. It is shown that the contribution from the long-range divergent part of the Hamiltonian tends to zero as 1/M-2, where M is the extent of the troublesome lattice summations. Therefore, it is well justified to neglect such contributions in higher order many-body perturbation theory or coupled cluster treatments of the electronic structure for polymers. © 1997 John Wiley & Sons, Inc.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 70 (1998), S. 1003-1007 
    ISSN: 0020-7608
    Keywords: dications ; coupled-cluster calculations ; penta coordinate nitrogen ; Chemistry ; Theoretical, Physical and Computational Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The dication NH52+ has been studied by state-of-the-art quantum chemical techniques. NH52+ is a square-based pyramid with C4v symmetry. The apical H is bonded to N with a 2-electron covalent bond, while the other H atoms are bonded to N through degenerate 2-electron 3-center bonds. No other local minimum exists on the potential energy surface. A C2v transition state linking equivalent C4v structures is only 1.35 kcal mol-1 higher in energy. The barrier to deprotonation is 26.4 kcal mol-1.   © 1998 John Wiley & Sons, Inc. Int J Quant Chem 70: 1003-1007, 1998
    Additional Material: 1 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...