Abstract

The structural and magnetic properties of the [formula omitted] compounds, where x is 0, 1, 2, 3, and 3.8, have been investigated by means of powder x-ray diffraction, thermomagnetic and ac magnetic susceptibility measurements, and iron-57 Mössbauer spectroscopy. The Dy2Fe17Hx compounds crystallize in a hexagonal Th2Ni17 -like structure which has both an iron-rich stoichiometry and disorder of the Dy and Fe–Fe dumbbell sites. The increase in the lattice parameters, the magnetic ordering temperature, the saturation magnetization, and the dependence of the Mössbauer hyperfine parameters upon hydrogen content support a two-step filling by hydrogen of the interstitial sites with hydrogen first filling the octahedral 6h sites for x < 3 and then partially filling the tetrahedral 12i sites for x = 3 and 3.8. Neither the Mössbauer spectra nor the ac magnetic susceptibility measurements reveal any spin reorientation in any of the compounds. The extent of the excess iron and the disorder observed in all the compounds is confirmed by the Mössbauer spectra and the hyperfine parameters of the iron 4e sites are reported herein for the first time. Finally, the Mössbauer spectra indicate that the interstitial hydrogen atoms partially occupying the tetrahedral 12i sites are jumping between these sites on the Mössbauer time scale. © 2000, American Institute of Physics. All rights reserved.

Department(s)

Chemistry

Publication Status

Available Access

Comments

National Science Foundation, Grant DMR95-21739

International Standard Serial Number (ISSN)

1089-7550; 0021-8979

Document Type

Article - Journal

Document Version

Final Version

File Type

text

Language(s)

English

Rights

© 2024 American Institute of Physics, All rights reserved.

Publication Date

01 Sep 2000

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