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Comparative study of unconventional 1s basis functions for the 1Σ ground state of H2 and He

✍ Scribed by Jean-Claude Leclerc

Publisher
John Wiley and Sons
Year
1976
Tongue
English
Weight
812 KB
Volume
10
Category
Article
ISSN
0020-7608

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✦ Synopsis

Abstract

We investigated various nonstandard 1__s__ basis functions (generalized Slater‐Gaussian, ellipsoidal Gaussian, floating spherical and ellipsoidal Gaussian, rational function, Hulthén approximation, two‐Slater‐type orbital, generalized Guillemin–Zener function, and various noninteger‐n elliptical orbitals) for approximating the ^1^Σ ground state of H~2~ and He~2~^++^. A CI trial wave‐function including Σ~g~‐type MO's is adopted and molecular integrals are evaluated numerically. The energy improvement on the 1__s__ STO is small except for noninteger‐n orbitals which closely approach the “SCF limit”.

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