The temperature dependent hyperfine interactions of the Fe-57 nuclei in the hexagonal rare earth intermetallic compounds of the form RFe3 have been studied using the Mossbauer effect. The resultant spectra have been investigated using a model which takes into account(1) the local point symmetry of the three distinct iron sites and (2) the differing local dipolar fields in these compounds. From this analysis it is possible to conclude that (1) YFe3,GdFe2.9 TbFe3 and DyFe3 magnetize along the b-axis;(2) HoFe3 changes its direction of magnetization from an a-axis to a b-axis at 87oK;(3) ErFe3 magnetizes along the c-axis. In addition Mossbauer studies on the pseudo-binary compounds R(Fe1-xCoX3) and R(Fe1-xNix3) where O < X < 0.7 have also been carried out. It is found that the replacement of Fe by Co or Ni leads to pronounced effects in th FE-57 Mossbauer spectra, the lattice parameters and the ordering temperatures of these compounds. Similarities between the pure Fe-Co and Fe-Ni binary alloys and the pseudo-binary R(Fe1-xMx2) and R2(Fe1-xMx17) compounds, where M= Co or Ni, are also noted.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:601472 |
| Date | January 1974 |
| Creators | Arif, Sherif Kamel |
| Publisher | University of Manchester |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
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