Use of STOs in Hartree-Fock calculations: Error analysis and variance-minimized pseudospectral method

✍ Scribed by Kennedy, H. L.; Zhao, Y.

• Publisher: John Wiley and Sons
• Year: 1999
• Tongue: English
• Weight: 194 KB
• Volume: 20
• Category: Article
• ISSN: 0192-8651
• DOI: 10.1002/(sici)1096-987x(19991115)20:14<1537::aid-jcc7>3.0.co;2-p

✦ Synopsis

In this study it is demonstrated that STO Slater-type orbital basis sets are particularly well suited to pseudospectral Hartree᎐Fock Ž . calculations. The reduction of two-electron integrals, to ones that are at worst equivalent to a one-electron integral over three centers, eliminates the need for slowly convergent one-center expansions. This allows all integrals to be calculated quickly and accurately in either spherical or ellipsoidal coordinates. A new variance-minimized variant of the pseudospectral method is derived and applied to a number of small closed-shell molecules. The performance of the algorithm is assessed relative to purely spectral calculations employing STO and Ž . GTO Gaussian-type orbital basis sets. The pseudospectral operator is used to assess the errors contained in solutions found by the purely spectral method. The suitability of a number of different de-aliasing set types is also examined. Orthogonal sets of hydrogen-like eigenfunctions were found to be optimal.