Structural Magnetic and Electrical Properties in Nd-Doped Manganites (La0.70−x Nd x )Sr0.30Mn0.70Ti0.30O3 with 0 ≤ x ≤ 0.30

Abstract

International audienceThe structural, magnetic and electrical properties of (La0.70−xNdx)Sr0.30Mn0.70Ti0.30 O 3 perovskites (0 ≤ x ≤ 0.30) prepared by the usual ceramic procedure were investigated. Structural Rietveld refinements of the X-ray powder diffraction revealed that for x = 0 the compound crystallizes in a rhombohedral (R 3¯ c) perovskite structure, while for x = 0.10, 0.20 and 0.30 the structure becomes orthorhombic (Pbnm). The field-cooled, zero-field-cooled and M(H) measurements lead to conclude that the samples with x≥0.10 behave like spin-glass systems. The temperature dependence of the resistivity exhibits two transitions at two temperatures T p1 and T p2, with the same width for the two peaks. T P1 results from the competition between double-exchange and super-exchange mechanisms inside the grain (intrinsic effects) whereas T P2 arises due to the grain boundary effects (extrinsic effect). The resistivity of this system seems to be related to the competition between antiferromagnetic insulating (AFI) phases, ferromagnetic insulating (FMI) phases and ferromagnetic metal (FMM) phases, which is induced by Nd doping effect

The Polar/Antipolar Phase Boundary of BiMnO3–BiFeO3–PbTiO3: Interplay among Crystal Structure, Point Defects, and Multiferroism

“…Manganese oxides and doped manganese oxides can be easily found having mixed valence states, for which spin‐glass behavior has been reported . This has been described as a low‐temperature electronic phase separation, in which large ferromagnetic domains are present within an antiferromagnetic matrix.…”

Study of the electrical and dielectric measurements of a rare-earth doped perovskite La0.6Nd0.1Sr0.3Mn0.7Ti0.3O3

“…mentioning that the deviation of tolerance factor t from the ideal value (t = 1) can be used as a measure of the internal strain in ABO 3 perovskite. However, in our sample (t \ 1), the strain is accompanied by a tilt and rotation of oxygen octahedra, resulting in a deviation of (Mn/Ti)-O-(Mn/Ti) bond angles to 163°away from the ideal value of 180° [23]. A simple consequence of the deviation of the bond angle from 180°is a decrease in the hopping amplitude since the electron transfer between the (Mn/Ti) sites occurs via the O2p states.…”

“…and Sr 2? occupy the A-site and Mn and Ti occupy the B-site [23]. IR absorption spectrum exhibits two strong absorption peaks.…”

“…The structure refinement is carried out by Rietveld analysis [28] of X-ray powder diffraction data using the FullProf software (version January 2006-LLB-LCSIM). Our sample crystallizes in orthorhombic structure with Pbnm space group [23]. mentioning that the deviation of tolerance factor t from the ideal value (t = 1) can be used as a measure of the internal strain in ABO 3 perovskite.…”

Influence of Al-doping on the structural, magnetic, and electrical properties of La0.8Ba0.2Mn1−Al O3 (0 ⩽ x ⩽ 0.25) manganites

“…One of these compounds is La 1−x Ba x MnO 3 (LBMO) manganite. [15][16][17][18][19] . As trivalent La 3+ ions are replaced with a divalent Ba 2+ in LaM nO 3 manganite, some of the manganese ion valence changed from M n 3+ (with the electronic configuration 3d 4 , t 3 2g e 1 g , S=2) to M n 4+ (with the electronic configuration 3d 4 , t 3 2g e 0 g , S=3/2) due to introducing holes into the this material.…”