Specific many-electron effects in X-ray spectra of simple metals and graphene

TL;DR

This paper investigates many-electron effects on X-ray spectra of simple metals and graphene using ab initio and semi-empirical methods, achieving good agreement with experimental data.

Contribution

It introduces a combined ab initio and semi-empirical approach to analyze many-electron effects in X-ray spectra of metals and graphene.

Findings

Theoretical spectra match experimental data well.

Dynamical screening and Auger effects significantly influence spectra.

Method effectively captures many-electron effects in X-ray spectra.

Abstract

In this work the influence of many-electron effects on the shape of characteristic X-ray emission bands of the simple metals Mg and Al are examined by means of ab initio calculations and semi-empirical models. These approaches are also used for the analysis of C K-emission and absorption spectra of graphene. Both, the dynamical screening of the core vacancy and the Auger-effect in the valence band (VB) have been taken into account. Dynamical screening of the core vacancy by valence electrons (the so-called MND effect) is considered ab initio in the framework of density functional theory. The Auger effect in VB was taken into account within a semi-empirical method, approximating the quadratic dependence of the VB hole level width on the difference between the level energy and the Fermi energy. All theoretical spectra are in very good agreement with available experimental data.