Role of exchange and correlation potential in calculating x-ray absorption spectra of half-metallic alloys: Mn and Cu K -edge XANES in Cu2 MnM Heusler alloys (M=Al, Sn, In)

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 Cu2 MnM (M=Al, Sn, and In) Heusler alloys. Our results show that ab initio single-channel multiple-scattering calculations are able to reproduce 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 x-ray absorption near edge structure features are discussed.