Magnetic splitting in x-ray photoelectron spectroscopy Cr L spectra of Fe2CrAl, Co2CrAl and Cu2CrAl

We have investigated various Cr-based Heusler alloys using core-level x-ray photoelectron spectroscopy (XPS). Of special interest are the 2p XPS lines , which always exhibit magnetic splitting in the case of the existence of a well-defined local magnetic moment at the transition metal site. The Cr 2p XP spectra, however, do not exhibit this exchange splitting for the nonmag netic Cu2CrAl sample and for Fe2CrAl or Co2CrAl alloys with a magnetic mome nt at the Cr sites of about 1.6 mu (B). This behaviour is discussed here.