Ab initiocalculation of the3sand1score-level x-ray photoemission spectra of iron

Abstract

We develop a method of the ab initio calculation for the core-level x-ray photoemission spectroscopy ͑XPS͒. By calculating one-electron states in the presence of core-hole potential, excited states are constructed by distributing electrons on these one-electron states. The overlap integrals between the excited states and the ground state are evaluated by using the wave functions with and without the core-hole potential, and finally the XPS spectra are obtained. Implementing the procedure, we obtain the spin-resolved 3s-core XPS spectra in ferromagnetic iron without any adjustable parameters, in good agreement with the experiment. The spectral shapes are quite different for different spin channels. We explain the behavior in terms of the difference in the one-electron states screening the core-hole potential.

Renormalization offlevels away from the Fermi energy in electron excitation spectroscopies: Density-functional results for Nd2−xCeJarlborg1, Barbiellini2, Lin3 et al. 2011Phys. Rev. B

“…This allows us to delineate relative differences in the way localized bands get excited in comparison to the itinerant bands. Our computations are based on the final state rule and the ∆-self-consistent field (∆SCF) method, which have been invoked previously to investigate x-ray absorption and emission [6][7][8], and x-ray photoemission spectroscopy (XPS) of core levels [9]. The final state rule postulates that the electronic structure of the excited state can be obtained by using the potential of the final state in which the hole is present in the valence band, i.e.…”

Ab initiostudy of2pcore-level x-ray photoemission spectra in ferromagnetic transition metals

“…7 We have clarified the origin of the satellite intensity on the 3s spectra and that the satellite intensity is not a direct reflection of the local spin moment by calculating the XPS spectra on the ab initio level. 15,16 For the strongly correlated localized electron systems such as the 3d transition metal oxides and the f -electron systems, the theoretical analysis of the XPS spectra have been carried out mainly on the basis of atomic, cluster, or impurity Anderson models. 17 Although the impurity Anderson model has been applied to analyze the corelevel spectra in some itinerant metallic systems, 12,18 it is not suitable to analyze the spectra in the highly itinerant metallic systems.…”

“…Recently we have presented the XPS spectra based on the ab initio band structure calculation. 15,16 We have calculated the final state potential self-consistently by carrying out the band structure calculation on the system holding a core-hole at a photo-excited site. Not only the core-hole potential but also the relaxation of the core states as well as the screening electron distribution are automatically determined through the calculation.…”

“…The element and photo-electron-spin dependence of the spectral line shape have been reproduced in good agreement with experiments within the ab initio manner. 15,16 This method may be regarded as an extension of the Feldkamp-Davis method 6 to an ab initio level. The origin of the spectral shape as a function of the binding energy has been elucidated in terms of the one-electron states screening the core-hole as follows.…”

Ab initiostudy of3score-level x-ray photoemission spectra in transition metals

“…We have developed an ab initio method to calculate the XPS spectra by extending the theory of Feldkamp and Davis. 6,19 Here we briefly summarize the procedure of calculation. First, we carry out the band structure calculation within the local density functional approximation (LDA) to obtain the one-electron states in the ground state.…”