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Internet Electronic Journal of Molecular Design - IEJMD, ISSN 1538-6414, CODEN IEJMAT
| ABSTRACT - Internet Electron. J. Mol. Des. February 2004, Volume 3, Number 2, 83-92 |
Molecular Three-Center Electronic Integrals Over Slater-Type Orbitals
Evaluated Using Nonlinear Transformations
Hassan Safouhi and Lilian Berlu
Internet Electron. J. Mol. Des. 2004, 3, 83-92
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Abstract:
Molecular three-center electronic integrals over Slater-type
orbitals are required for ab initio and density functional
theory (DFT) molecular structure calculations. They occur in
many millions of terms, even for small molecules and require
rapid and accurate evaluation. In this work, we present a very
efficient approach based on properties of Bessel and sine
functions and on nonlinear transformations for accurate
numerical evaluation of integrals under consideration.
Numerical results are obtained for three-center nuclear and
three-center two-electron Coulomb and hybrid integrals over
Slater-type orbitals for HCN, C2H2,
Zn3, BH3, and CH4
molecules. We also performed the same calculations using
existing codes to show the accuracy of the new algorithm.
The results obtained in this work illustrate the efficiency of
the algorithm based on the SD approach, which will lead to a
definitive suite of ab initio Slater software.
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