Role of the exchange and correlation potential into calculating the x-ray absorption spectra of half-metallic alloys: the case of Mn and Cu K-edge XANES in Cu$_2$MnM (M = Al, Sn, In) Heusler alloys

TL;DR

This study investigates how the exchange and correlation potential influences the accuracy of ab-initio calculations of X-ray absorption spectra in half-metallic Cu$_2$MnM Heusler alloys, emphasizing the importance of final state potentials.

Contribution

It demonstrates the significance of the exchange and correlation potential and cluster size in accurately reproducing experimental XANES spectra for these alloys.

Findings

Ab-initio multiple-scattering calculations match experimental spectra.

Exchange and correlation potentials are crucial for accurate spectral features.

Final state potential effects are significant in modeling half-metallic alloys.

Abstract

This work reports a theoretical study of the x-ray absorption near-edge structure spectra at both the Cu and the Mn K-edge in several Cu$_2$MnM (M= Al, Sn and In) Heusler alloys. Our results show that {\it ab-initio} single-channel multiple-scattering calculations are able of reproducing the experimental spectra. Moreover, an extensive discussion is presented concerning the role of the final state potential needed to reproduce the experimental data of these half-metallic alloys. In particular, the effects of the cluster-size and of the exchange and correlation potential needed in reproducing all the experimental XANES features are discussed.