The structural and magneto-transport properties of electron-doped manganites (La1_xPrx)0.85Zr0.15MnO3 (Pr-doped LZMO) with x ? 0, 0.05, 0.10, 0.15, and 0.20 have been investigated. X-ray diffraction (XRD) patterns show that the Pr-doped LZMO has rhombohedral lattice structure with R¯3C space group. The Mn–O–Mn bond angle of the system refined by Rietveld technique decreases with increasing Pr content ranging from 165.381 for x ? 0 to 163.641 for x ? 0:20. A significant distortion of the MnO6 octahedra caused by the distinctively small Mn–O–Mn bond angle weakens the strength of Mn2+–O–Mn3+ double exchange (DE) interaction. The Curie temperature TC increases with increasing average A-site ionic radius, /rAS, and the magnetoresistance (MR) ratio decreases with increasing /rAS, strongly suggesting that the DE mechanism plays an important role in the charge transport property of the Pr-doped LZMO.
關聯:
Journal of Magnetism and Magnetic Materials 304, pp.e340-e342
