A study of the influence of aluminum on the magnetic interactions in Tb{sub 2}Fe{sub 17-x}Al{sub x}
- Univ. of Missouri, Rolla, MO (United States); and others
The magnetic properties of the rhombohedral Tb{sub 2}Fe{sub 17-x}Al{sub x} solid solutions with x between 2 and 8 have been studied by neutron diffraction and Mossbauer spectroscopy. Aluminum shows no site preference for x{<=}6 but a pronounced preference for the 6c and 18f Fe sites for x>6. Because of the presence of diamagnetic Al, the Mossbauer spectra have been fit with a distribution of near-neighbor environments at the Fe sites. The maximum hyperfine fields, H{sub max}, are in the order 6c>9d>l8f>18h. The average maximum hyperfine field decreases by 10kOe/Al at 85K for x{<=}7 and by 7kOe/Al at 295K for x=2, 3, and 4. Paramagnetic behavior is observed at 295K for x>4. The average reduction in the hyperfine field per Al near neighbor decreases by ca. 2kOe/Al for x{<=}7 at 85K and for x{<=}5 at 295K. The average isomer shift increases with Al content because of both the increase in the unit cell volume and the screening of the Fe 4s electrons by the additional 3d conduction band electrons resulting from electron transfer from the Al atoms. These transferred electrons fill a hole in the 3d band, and, as a result, lower the hyperfine field and the magnetic moment for x{>=}4. Apparently the Al does not act as a simple magnetic hole but rather produces an accumulative decrease in the hyperfine field.
- OSTI ID:
- 214966
- Report Number(s):
- CONF-950801-; TRN: 96:000922-0457
- Resource Relation:
- Conference: 210. national meeting of the American Chemical Society (ACS), Chicago, IL (United States), 20-25 Aug 1995; Other Information: PBD: 1995; Related Information: Is Part Of 210th ACS national meeting. Part 1 and 2; PB: 1866 p.
- Country of Publication:
- United States
- Language:
- English
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