Page 208 - Strategies and Applications in Quantum Chemistry From Molecular Astrophysics to Molecular Engineer

FSGO HARTREE-FOCK INSTABILITIES OF HYDROGEN 191

two-electron integrals:

In the RHF method, the FSGO describing the electron pairs is doubly occupied and the
wave-function has the form:

Its associated RHF energy is, at a given internuclear distance (R):

Table 1. shows the total energies obtained using the RHF method for: 1. LCAO minimal
basis set STO-1G for the sake of comparison with FSGO, 2. FSGO in its symmetric and
broken symmetry solutions and, 3. LCAO minimal basis set STO-3G in order to allow a
safer comparison with the quality of the subminimal basis used in the FSGO technique.
The dissociation curves are given in Figure 1.