Publication: Structural and magnetic properties of Pr<inf>3</inf>(Fe<inf>1-x</inf>Co<inf>x</inf>)<inf>27.5</inf>Ti-<inf>1.5</inf> (x = 0.0, 0.1, 0.2, 0.3)
Date
15-12-1998
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Abstract
A novel class of Co-substituted 3 : 29 materials, Pr3(Fe1-xCox)27.5Ti1.5 (x = 0, 0.1, 0.2, 0.3) have been synthesized. Rietveld analysis of X-ray powder diffraction patterns for the x = 0,0.1 and 0.2 compositions showed that nearly all of the compounds are formed in monoclinic symmetry, with A2/m space group with traces of α-Fe, whereas, in x = 0.3, additional traces of a (Co/Fe)-Ti (1: 12) phase are also seen. The saturation magnetization increases with Co concentration both at 5 and 300 K and is explained on the basis of a rigid band model. A magnetic transition is observed for x = 0.1 near 240 K. A large increase in Curie temperature, of about 180 K for x = 0.1 and about 110 K for the other concentrations, is discussed on the basis of the strengthening of TM-TM exchange by the preferential occupation of Co in some of the Fe sites originally participating in antiferromagnetic bonds. © 1998 Elsevier Science B.V. All rights reserved.
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3 : 29 compounds, Antiferromagnetic bonds, R-TM intermetallics, Rietveld analysis, TM-TM exchange