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تسجيل مستخدم جديدCorrelation between the tolerance factor and phase transition in Ln4-xLnxNi3O10 (Ln and Ln = La, Pr and Nd; x = 0, 1, 2 and 3)
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We have synthesized a series of the Ruddlesden-Popper nickelate solid solution Ln4-xLnxNi3O10 (Ln and Ln = La, Pr and Nd; x = 0, 1, 2 and 3) via the citrate precursor method at different reacting atmospheres. Both the electronic-transport and magnetization measurements on these samples show well-defined phase transitions at temperatures between 135 K and 165 K. These transition temperatures, the room-temperature resistivities, as well as the changes of the Pauli-paramagnetic susceptibilities at the respective phase transitions, strongly correlate with the Goldschmidt tolerance factor t, irrespective of the combination of the magnetic rare-earth ions with unmagnetic La3+. We conclude that these changes of the electronic properties are mostly related to the distortion of the NiO6 octahedra at the phase transition which is strongly correlated with the tolerance factor t, but are rather insensitive to the magnetism of the rare-earth ions Ln3+ and Ln3+.
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