Cerium M-Edge X-ray Absorption and an Iron L-Edge Magnetic Circular Dichroism Study of the Ce₂Fe₁₇₋ₓMₓ Solid Solutions, Where M Is Al and Si

Author

Fernande Grandjean, Missouri University of Science and TechnologyFollow
George Daniel Waddill, Missouri University of Science and TechnologyFollow
Tom R. Cummins
D. P. Moore
Gary J. Long, Missouri University of Science and TechnologyFollow
K. H. J. Buschow

Abstract

The cerium M-edge X-ray absorption spectra and the iron L-edge magnetic circular dichroism spectra of the Ce₂Fe_17-xM_x solid solutions, where M is aluminum and silicon, were measured at room temperature. The cerium M-edge spectra was used to determine the variation in the valence of cerium in the solid solutions. The resulting values, which range from 3.20 in Ce₂Fe_16.8Si_0.2 to 3.02 in Ce₂Fe₆Al₁₁, decrease linearly with x in both series, but the decrease is twice as large in Ce₂Fe_17-xSi_x. Interestingly, the resulting valencies are quantitatively different from those determined using cerium L-edge X-ray absorption data, but the qualitative trends in the valence with metalloid substitution is the same using either the cerium L- or M-edge data. The cerium valencies also correlate linearly with the cerium Wigner-Seitz cell volumes, but with a positive slope for the silicon and a negative slope for the aluminum solid solutions. This difference results because of the more extensive cerium-silicon covalent bonding interaction in Ce₂Fe_17-xSi_x as compared to the cerium-aluminum interaction in Ce₂Fe_17-xAl_x. The iron L-edge magnetic circular dichroism spectra indicate that a non-zero iron orbital moment is coupled parallel to the iron spin moment. The orbital moments range from 0.0 to 0.2 µ_B and reveal that the orbital moments are probably independent of x and are ca. 0.07 µ_B for both series of solid solutions. The cerium M-edge magnetic circular dichroism spectra reveal no dependence upon the relative orientation of the magnetization or the photon helicity, indicating that there is no 4f magnetic moment associated with cerium in these solid solutions.

Recommended Citation

F. Grandjean et al., "Cerium M-Edge X-ray Absorption and an Iron L-Edge Magnetic Circular Dichroism Study of the Ce₂Fe₁₇₋ₓMₓ Solid Solutions, Where M Is Al and Si," Solid State Communications, vol. 109, no. 12, pp. 779 - 784, Elsevier Science Ltd, Mar 1999.

The definitive version is available at https://doi.org/10.1016/S0038-1098(98)00623-1

Department(s)

Chemistry

Second Department

Physics

Keywords and Phrases

Aluminum; Cerium Compounds; Magnetization; Silicon; Solid Solutions; X Ray Spectroscopy; L-edge Magnetic Circular Dichroism; Wigner-Seitz Cell Volumes; Magnetic Materials

International Standard Serial Number (ISSN)

0038-1098

Document Type

Article - Journal

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 1999 Elsevier Science Ltd, All rights reserved.

Publication Date

01 Mar 1999