Polaron hopping conduction mechanism and magnetic properties of Pb‐doped LaMnO₃

Abstract

For the last several years, ABO 3 -type perovskites (A is either a rare earth metal or an alkaline earth metal cation and B is a 3d transition metal cation) have fascinated global concern owing to their strong association among spin, charge, lattice, and orbital degrees of freedom and remarkable assets such as electrical, mechanical, optical, magnetic, catalytic, ferroelectric, colossal magnetoresistance (CMR), high T c superconductivity, non-volatile memory phenomena, etc. [1][2][3] In this class, manganites are materials with great technological value in several device applications, including CMR. 2 One of the key features of manganites as compared to other oxides families is the broad range of

The Structural and Magnetic Transition Behaviour Analysis of La0.7Pb0.3MnO3 Perovskite-Type Manganites

“…Other relevant information, such as lattice parameters and unit volume, were also determined through the Rietveld refinement software, where a = b = 5.5333, c = 13.3943 and V = 355.167 A 3 . These findings are consistent with the conclusions of a previous study [8]. The structure of La0.7Pb0.3MnO3 was constructed using visualisation for electronic and structural analysis (VESTA) software.…”

“…Electron hopping from Mn 3+ to Mn 4+ improves significantly with the increase of the bond angle. The Mn ̶ O ̶ Mn bond angle and the Mn ̶ Mn bond are highly correlated with the tilting of the neighbouring MnO6 octahedron [8].…”

“…Previous studies on magnetic properties of La1−xPbxMnO3 (x = 0-0.2) showed that properties are remarkably influenced by the compound structure. Magnetic hysteresis studies at room temperature (T = 300 K) demonstrated that the compound is paramagnetic for x = 0-0.1 compositions and ferromagnetic for x = 0.15-0.2 compositions, with maximum magnetisation values of 16.97 and 30.45 emu/g, respectively [8]. The transition can be attributed to the MnO6 octahedral distortion, which can be improved with the increase of Pb doping and subsequently increase the tolerance value τ from 0.851 for x =0 to 0.862 for x = 0.2.…”