title: Polarization propagator for x-ray spectra.
abstract: A polarization propagator for x-ray spectra is outlined and implemented in density functional theory. It rests on a formulation of a resonant-convergent first-order polarization propagator approach which makes it possible to directly calculate the x-ray absorption cross section at a particular frequency without explicitly addressing the excited states. The quality of the predicted x-ray spectrum relates only to the type of density functional applied without any separate treatment of dynamical relaxation effects.
authors.affiliation: Department of Physics, Chemistry and Biology, Linköping University, SE-581 83 Linköping, Sweden.
authors.forename: Ulf
authors.initials: U
authors.lastname: Ekström
authors.forename: Patrick
authors.initials: P
authors.lastname: Norman
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Carravetta
authors.forename: Hans
authors.initials: H
authors.lastname: Agren
mesh_terms: D000042:Absorption; D020029:Base Pairing; D003596:Cytosine / Q000737:chemistry*; D006147:Guanine / Q000737:chemistry*; D013052:Spectrometry, X-Ray Emission / Q000379:methods*
chemical_list: D006147:Guanine; D003596:Cytosine