Mössbauer and Magnetometric Studies of Spin Reorientations in Er2-xThxFe14B |
| A. Wojciechowska, B.F. Bogac and A.T. Pędziwiatr
M. Smoluchowski Institute of Physics, Jagiellonian University, Reymonta 4, 30-059 Kraków, Poland |
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| Received: 2005 20 05; |
| The Er2-xThxFe14B (x=0.5, 1.0, 1.5) polycrystalline compounds have been investigated with 57Fe Mössbauer spectroscopy in the 50-330 K temperature range and magnetometry in the temperature range of 4.2-340 K. Initial magnetization vs. temperature measurements allowed us to establish the temperature regions of reorientations and also the Curie temperatures of the compounds. The spin reorientation phenomena (changes from planar to axial spin arrangements) have been studied extensively by a narrow step temperature Mössbauer scanning in the vicinity of the spin reorientation temperatures. From the analysis of the obtained Mössbauer spectra it was deduced that in the region of transition each subspectrum was split into two Zeeman sextets, which were characterised by different hyperfine magnetic fields and quadrupole splittings. A consistent way of describing the Mössbauer spectra in the wide range of temperatures was proposed. The composition and temperature dependences of hyperfine interaction parameters and subspectra contributions were derived from experimental spectra. The transition temperatures were determined for all the compounds studied and the spin phase diagram was constructed. |
| DOI: 10.12693/APhysPolA.109.427 PACS numbers: 76.80.+y, 75.25.+z |