ISSN:
1089-7550
Source:
AIP Digital Archive
Topics:
Physics
Notes:
The structural and magnetic properties of the Dy2Fe17Hx 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.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.1287599
