Magnetic and structural properties of Lu2(Fe, Mn)17Hy hydrides
The Lu2Fe17−xMnxHy, x = 0–2, y = 0–3, hydrides with the Th2Ni17-type crystal structure were prepared and their structural and magnetic parameters were studied. The lattice parameters measured at room temperature increase smoothly with H content. The magnetic measurements indicate that the Lu2Fe17Hy hydrides (with y up to 1.77) are antiferromagnets at high temperatures and ferromagnets at low temperatures. The Lu2Fe16.5Mn0.5 compound also has a high temperature antiferromagnetic state, but its hydrides are ferromagnets only. The Lu2Fe17−xMnxHy hydrides, with x = 0.7 and 2, are ferromagnets with Tc monotonically increasing with H content. The saturation magnetization measured for Lu2Fe17−xMnxHy, (x = 0,0.5,0.7,2 and 0
Magnetic properties of Lu2Fe17 crystals
Abstract We present the results of crystal structure and magnetization studies of three single crystals grown from melts of different nominal compositions in the vicinity of the Lu2Fe17 stoichiometry. The ferromagnetic state of the crystals is strongly dependent on the real sample composition and the local atomic ordering. A drastic difference is observed in the behaviour of the ferro–antiferromagnetic transition, even in crystals for which almost identical composition and crystal parameters were determined by microprobe and X-ray analysis.
Magnetic and structural properties of Nd2Fe17−xMnx solid solutions
A series of Nd2Fe17−xMnx solid solutions with x values between 0 and 6 were prepared and analyzed using magnetic measurements, neutron diffraction, and Mossbauer spectroscopy. All of the Nd2Fe17−xMnx samples crystallized in the Th2Zn17−x-type rhombohedral structure. The lattice parameters and unit cell volumes decrease with increasing manganese content up to ∼x equal to 2, and then increase for higher manganese content. The magnetizations of Nd2Fe17−xMnx decrease with increasing manganese content and Nd2Fe17−xMnx is paramagnetic at room temperature for x greater than 3. The Curie temperature in Nd2Fe17−xMnx solid solutions is maximum for x equal to 0.5 and decreases at a rate of ∼10° per substituted manganese up to x equal to 3, after which it drops sharply. These results are discussed in terms of the manganese site occupancies in Nd2Fe17−xMnx.