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FSGO

Table 18.1 Input and output from an FSGO calculation on ammonia... Table 18.1 Input and output from an FSGO calculation on ammonia...
Some authors also recommended that the inner-shell octet of a second-row atom should be represented by four doubly occupied FSGOs arranged tetrahe-drally round the nucleus. [Pg.304]

FSGO Hartree-Fock Instabilities of Hydrogen in External Electric Fields... [Pg.189]

With respect to correlation, the behaviour of the hydrogen molecule studied in a subminimal FSGO basis set is still more striking than the one observed in a minimal basis set. By symmetry arguments, the single FSGO which describes the electron pair of the hydrogen molecme is centred at the middle of the H-H bond. As the intemuclear distance increases and ultimately when the molecule dissociates, such a description would lead to a physical nonsense. Indeed, at the dissociation limit, this would correspond to two protons (2H ) and an isolated pair of electrons (2e ). [Pg.190]

Thus, we understand that, in the FSGO model, for some critical distance, the single Gaussian will jump from its symmetric position at the middle of the H-H bond to a dissymetric one represented below. Thus, the FSGO dissociation scheme corresponds to one electron pair on one of the proton (H )and no electron on the second proton (H+) H2 H- + H+... [Pg.190]

FSGO HARTREE-FOCK INSTAB HUES OF HYDROGEN... [Pg.191]

In the RHF method, the FSGO describing the electron pairs is doubly occupied and the wave-function has the form ... [Pg.191]

Table 1. shows the total energies obtained using the RHF method for 1. LCAO minimal basis set STO-IG 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. [Pg.191]

The equilibrium FSGO-hydrogen molecule is found for the parameters ... [Pg.192]

In both cases, the energy formula (E(UHF-FSGO)) is the same ... [Pg.192]

Note that the PHF wave function is no longer a single determinant and is a sum of two terms. This PHF function both satisfies the Pauli principle and is a pure singlet state. The energy formula E(PHF-FSGO) is easily derived ... [Pg.194]

Table 2. Total energy as a function of the internuclear distance R, in FSGO... Table 2. Total energy as a function of the internuclear distance R, in FSGO...
In the Extended Hartree-Foek (EHF) technique, the minimization is performed on the form of the PHF wave function. This type of wave function should produce for each interatomic distance a further lowering of the energy with respect to the RHF, UHF, and PHF total energies. The values of E(PHF-FSGO), and E(EHF-FSGO) for internuclear distances from 1.0 a.u. to 7 a.u. (step 0.5 a.u.) are also given in Table 2. As in the UHF... [Pg.195]

In all the other sehemes (UHF, PHF, EHF), the dissociation limit is the correct one corresponding to two neutral hydrogen atoms (2H-) each FSGO-hydrogen atom energy is thus obtained by the simple variational procedure ... [Pg.196]

When expressing the nuclear attraction integrals in the FSGO basis, one has explicitly ... [Pg.197]

The optimal positions of the FSGO orbital correspond to the minima of the function E(zg). They may be found by imposing the necessary condition dE... [Pg.198]

By performing the derivative of the error function, one finds easily that the optimal position ZG of the FSGO necessarily satisfies the following equation ... [Pg.198]

FSGO Hartree-Fock instabilities of hydrogen in external electric fields... [Pg.472]

Development of the OLPA/FSGO treatment of molecular stopping 341... [Pg.335]


See other pages where FSGO is mentioned: [Pg.302]    [Pg.302]    [Pg.303]    [Pg.304]    [Pg.304]    [Pg.189]    [Pg.190]    [Pg.190]    [Pg.190]    [Pg.191]    [Pg.191]    [Pg.192]    [Pg.193]    [Pg.193]    [Pg.193]    [Pg.193]    [Pg.194]    [Pg.194]    [Pg.195]    [Pg.195]    [Pg.195]    [Pg.195]    [Pg.195]    [Pg.196]    [Pg.197]    [Pg.197]    [Pg.199]    [Pg.201]    [Pg.341]   
See also in sourсe #XX -- [ Pg.302 ]

See also in sourсe #XX -- [ Pg.302 ]




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The Floating Spherical Gaussian (FSGO) Model

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