Journal of Mathematical Chemistry

, Volume 20, Issue 2, pp 263–271 | Cite as

A procedure to obtain an accurate approximation to a full CI wavefunction

  • Ramon Carbó-Dorca
  • Emili Besalú
Article
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Abstract

Based on Jacobi elementary rotations, a simple, elegant procedure to obtain approximate CI wavefunctions is discussed. Essentially, a sequence of (2 x 2) matrices is builtup, and the eigenvector attached to the lowest eigenvalue is used to construct a stepwise set of coefficients, which become a very good approximation to theexact Cl result. Full CI calculations could easily be reached in this way. An example formed by some atoms of the He isoelectronic sequence is provided in order to test the flexibility and accuracy of the procedure. A Fortran 90 code is available.

Keywords

Physical Chemistry Accurate Approximation Lower Eigenvalue Elementary Rotation Isoelectronic Sequence 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.
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Copyright information

© J. C. Baltzer AG, Science Publishers 1996

Authors and Affiliations

  • Ramon Carbó-Dorca
    • 1
  • Emili Besalú
    • 1
  1. 1.Institute of Computational ChemistryUniversity of GironaGirona, CatalunyaSpain

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