Transition metals Hartree-Fock term values

F irst, consider the d-state energy, c,. The only serious discrepancy between Mattheiss s calculation and the experimental optical spectra was that Mattheiss s calculation appeared to overestimate the band gap by about three electron volts. Since this gap is dominated by the energy i — r,p, the discrepancy suggested an overestimate of this difference. In fact, his calculated bands were positioned roughly in accord with the splitting predicted by term values of Herman and Skillman (1963). Finally, the same overestimate applies to the Herman-Skillman term values in comparison to Hartree-Fock term values. This suggested, then, that values for e, should be taken from Hartree-Fock calculations, and those are what appear in the Solid State Table and therefore also in Table 19-3. C. Calandra has suggested independently (unpublished) from consideration of transition metals... 

Hartree-Fock term values after Mann (1967), in eV. In the upper part,e, values are given first for each element and p values are given next for the transition metals,... 

Consideration of Hartree-Fock term values from Fischer (1972), as discussed in Appendix A, indicates that Hartree-Fock values for valence s- and p-state energies are quite similar to the Herman-Skillman values given in the Solid State Table. Thus a more systematic treatment would result from use of the Hartree-Fock values throughout they are more appropriate for the transition metals and it would make little difference which set of values is used for other systems. The reasons for retaining Herman-Skillman values here are largely historical it is also possible that use of Hartree-Fock values would increase discrepancies with existing band calculations since, as indicated in Appendix A, the approximations almost universally used in solids are the same as those used in the Herman-Skillman calculation. For s and p states the differences are small in any case. 

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