Berlin 2008 – wissenschaftliches Programm

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SYEC: Symposium Exact-exchange and hybrid functionals meet quasiparticle energy calculations

SYEC 4: Exact-exchange and hybrid functionals meet quasiparticle energy calculations IV

SYEC 4.9: Vortrag

Freitag, 29. Februar 2008, 12:15–12:30, A 151

Closing the gap to reality: non local exchange and correlations in metals — •Gernot Stollhoff — MPI f. Festkörperforschung, Heisenbergstr.1, D 70569 Stuttgart

The Local Ansatz (LA)is the only ab-initio correlation scheme that can be used for metals. Here, it will be demonstrated that non-local exchange and correlation contributions exist that are very relevant for metals but have never been treated before, and are not covered by any of the density functional (DF) schemes either. These contributions aim at reducing the long range charge fluctuations by lattice symmetry reductions, charge density wave instabilities or charge redistributions for the case of degenerate bands. Applications are presented for polyacetylene, Li (bcc, densely packed), Zn, V, Fe. In all cases, the DF results are deficient, and the LA corrections are verified by experiment. These corrections may also strongly influence electron-phonon coupling.