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Interelectronic repulsion

If we compare the calculated total ionization potential, IP = 4.00 hartiees, with the experimental value, IP = 2.904 hartiees, the result is quite poor. The magnitude of the disaster is even more obvious if we subtract the known second ionization potential, IP2 = 2.00, from the total IP to find t c first ionization potential, IPi. The calculated value of IP2, the second step in reaction (8-21) is IP2 = Z /2 = 2.00, which is an exact result because the second ionization is a one-election problem. For the first step in reaction (8-21), IPi (calculated) = 2.00 and IPi(experimental) = 2.904 — 2.000 =. 904 hartiees, so the calculation is more than 100% in error. Clearly, we cannot ignore interelectronic repulsion. [Pg.236]

Cl calculations can be used to improve the quality of the wave-function and state energies. Self-consistent field (SCF) level calculations are based on the one-electron model, wherein each electron moves in the average field created by the other n-1 electrons in the molecule. Actually, electrons interact instantaneously and therefore have a natural tendency to avoid each other beyond the requirements of the Exclusion Principle. This correlation results in a lower average interelectronic repulsion and thus a lower state energy. The difference between electronic energies calculated at the SCF level versus the exact nonrelativistic energies is the correlation energy. [Pg.38]

Assignment of (he observed bands to these transitions, provides an estimate of B, the Racah interelectron repulsion parameter. Its value (Table 23.6) is invariably below that of the fiee-ion (1030cm ) because (he expansion of d-electron charge on complexation reduces the inteielectronic repulsions. [Pg.1029]

Craig, D. P., Proc. Roy. Soc. [London) A202, 498, Electronic levels in simple conjugated systems. I. Configuration interaction in cyclobutadiene. (ii) All the interelectron repulsion integrals, three- and four-centered atomic integrals, are included. [Pg.329]

Brickstock, A., and Pople, J. A., Phil. Mag. 44, 697, The spatial correlation of electrons in atoms and molecules. III. The influence of spin and antisymmetry on the correlation of electrons/ A discussion is made of the refinement needed, if the interelectronic repulsion is taken into account beyond the single determinant, b. [Pg.334]

The nephelauxetic effect calculation and accuracy of the interelectronic repulsion parameters /, cubic high spin d1, d3, d7 and d systems. E. Konig, Struct. Bonding (Berlin), 1971, 9, 175-212 (64). [Pg.36]

It should be noted that the above conclusions have been reached on strictly electrostatic grounds a spin property has not been invoked for the two electrons. From the variation of i/i along the box it can be shown that the singlet state is of higher energy than the triplet because the two electrons are more crowded together for (S-state) than for (T-state). Thus there is less interelectronic repulsion m the T-state. The quantity 2J j. is a measure of the effect of electron correlation which reduces the repulsive force between the two electron (Fermi correlation energy). [Pg.63]

The approach we have adopted for the d configuration began from the so-called strong-field limit. This is to be contrasted to the weak-field scheme that we describe in Section 3.7. In the strong-field approach, we consider the crystal-field splitting of the d orbitals first, and then recognize the effects of interelectron repulsion. The opposite order is adopted in the weak-field scheme. Before studying this alternative approach, however, we must review a little of the theory of free-ion spectroscopy... [Pg.39]

We note that three spin-allowed electronic transitions should be observed in the d-d spectrum in each case. We have, thus, arrived at the same point established in Section 3.5. This time, however, we have used the so-called weak-field approach. Recall that the adjectives strong-field and weak-field refer to the magnitude of the crystal-field effect compared with the interelectron repulsion energies represented by the Coulomb term in the crystal-field Hamiltonian,... [Pg.48]

Again, we restrict discussion to spin-allowed transitions here. In general, of course, crystal field effects compete with interelectron repulsion for all d" configurations, exceptfor n = 1 or 9. [Pg.97]

Finally, we must remember that just as a d-d spectrum is not properly described at the strong-field limit - that is, without recognition of interelectron repulsion and the Coulomb operator - neither is a full account of the energies or number of charge-transfer bands provided by the present discussion. Just as a configuration... [Pg.114]


See other pages where Interelectronic repulsion is mentioned: [Pg.82]    [Pg.82]    [Pg.27]    [Pg.35]    [Pg.174]    [Pg.174]    [Pg.235]    [Pg.236]    [Pg.239]    [Pg.540]    [Pg.47]    [Pg.25]    [Pg.996]    [Pg.1087]    [Pg.1235]    [Pg.13]    [Pg.37]    [Pg.38]    [Pg.39]    [Pg.50]    [Pg.77]    [Pg.77]    [Pg.90]    [Pg.97]    [Pg.99]    [Pg.99]    [Pg.118]    [Pg.119]    [Pg.154]    [Pg.156]    [Pg.172]    [Pg.199]    [Pg.204]    [Pg.205]   
See also in sourсe #XX -- [ Pg.4 , Pg.20 , Pg.22 , Pg.39 ]




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Coulomb repulsion energy, interelectronic

Integrals interelectron repulsion

Interelectron repulsion energy

Interelectron repulsion matrix

Interelectronic Repulsion and Ligand Field Splitting When There Is Ambiguity in the d-Electron Configuration

Interelectronic repulsion Hamiltonian

Interelectronic repulsion configuration ambiguity

Interelectronic repulsion effect

Interelectronic repulsion energy

Interelectronic repulsion energy complexes

Interelectronic repulsion parameter

Interelectronic repulsion parameter for high-spin complexes of cobalt

Interelectronic repulsion parameters, decrease

Jorgensens Parametric Representation of Ligand Field Splitting and Interelectronic Repulsion

Racah interelectronic repulsion energy

Racah parameters of interelectronic repulsion

Repulsion, interelectron

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