Abstract
The magnetic susceptibility and X-ray photoelectron spectra of CeMn 4Al 8 and CeMn 6Al 6 and of the reference compounds YMn 4Al 8, CeCu 4Al 8, YMn 6Al 6 and LaMn 6Al 6 are reported. The occurrence of a Mn moment in the investigated compounds is strongly correlated with the critical value d≃2.6 Å of the Mn–Mn distance below which the Mn moment collapses. It is revealed that the magnetic character of the Mn moment in the crystallographic sites for which d Mn–Mn≤2.6 Å changes from an itinerant electron type to a local moment type with increasing temperature. This behavior is in agreement with the prediction of spin fluctuation theory. Both the magnetic susceptibility and Ce 3d and 4d XPS spectra confirmed the mixed valence state of Ce ions in CeMn 4Al 8 and CeMn 6Al 6. The f occupancy, n f, and coupling, Δ, between the f level and the conduction states are derived to be about 0.83 and 80 meV, respectively. The Mn 3s XPS splitting is discussed in terms of the time scale for the spin fluctuation and photoemission processes.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.