Band structure point charges

The main drawback of the chister-m-chister methods is that the embedding operators are derived from a wavefunction that does not reflect the proper periodicity of the crystal a two-dimensionally infinite wavefiinction/density with a proper band structure would be preferable. Indeed, Rosch and co-workers pointed out recently a series of problems with such chister-m-chister embedding approaches. These include the lack of marked improvement of the results over finite clusters of the same size, problems with the orbital space partitioning such that charge conservation is violated, spurious mixing of virtual orbitals into the density matrix [170], the inlierent delocalized nature of metallic orbitals [171], etc. 

In the preceding sections, we have rapidly reviewed the concepts that are involved in the band formation of actinide metals. We would like to point out what more is involved in the band formation of actinide compounds. This is very obvious the anion valence band. In fact, the hybridization with anion states which we presented as the main correction to the simple Hill scheme is indeed the central question involved in detailed band structure calculations in actinide compounds. We pointed out in the previous paragraph the case of UGea we would like here, as an example, to compare somewhat UO2 and NaCl compounds of uranium. As confirmed by recent photoemission studies " , UO2 has well localized 5 f states whereas NaCl compounds have a narrow 5 f band pinned at the Fermi level. Nevertheless the U-U spacing is the same in UO2, UP and US. This difference may be understood in terms of charge transfer versus f-p hybridization. 

When CV has D3 symmetry, calculated absorption bands are located at 546.2 and 534.5 nm from the lowest energy. When CV is deformed into C3 symmetry, we obtained red-shifted bands 562.0 and 550.1 nm (Table 3). No effect of a methanol molecule on the structure of a CV molecule other than the point-charge perturbation was considered in the current calculations. 

Initially, the ability of PVK to transport charges was assumed to be related to the spatially crowded structure of PVK (7), in which the carbazole groups, because of their covalent-bonding backbone, are forced to interact with each other to the point that significant orbital overlap creates a band structure. However, the observed mobilities were low cm /V-s),... 

As pointed out in the introduction a possible charge transfer in Zintl phases from the alkali to the non-alkali sublattice is often discussed in the literature. Therefore, there have been many attempts to calculate the charge transfer in these phases from band structure data. There is, however, no unique way to calculate a charge transfer. The various methods used and the resulting values for the Zintl phases are summarized in this subsection. 

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