J. Phys. IV France 123 (2005) 413-418
The effect of cation radii on structural, magnetic and electrical properties of doped manganites La0.6-xPrxSr0.4MnO3S. Zemni1, Ja. Dhahri1, J. Dhahri1, M. Oumezzine1 and H. Vincent2
1 Laboratoire de Physico-Chimie des Matériaux, Faculté des Sciences de Monastir, Département de Physique, 5019 Monastir, Tunisie
2 Laboratoire des Matériaux et de Génie Physique, ENSPG, BP. 46, 38402 Saint-Martin d'Hères Cedex, France
The effect of trivalent substitution into rare earth sites in La PrSr0.4MnO3 oxides has been studied. The structural, and magnetic properties of these compounds with a fixed Mn3+/Mn4+ ratio of 3/2 are studied. X-ray diffraction patterns show that these compounds are rhombohedral (R c) below x = 0.42 and become orthorhombic (Pbnm) above x = 0.42. The paramagnetic to ferromagnetic transition temperature T decrease from 374K to 310K when < r > decreases. The ionic radii variance decreases with the increase of < r >. The resistivity transition temperature T decreases from 350 K to 280 K as Pr content increases.
Key words: Perovskite, Manganite, Cation size.
© EDP Sciences 2005