Structural and electrical resistivity study of Mn-doped LaFe_1-xMn_xO₃ (x ≤ 0.5) crystals

¹ Department of Physics, Department of Higher Education, Govt. Degree College, Handwara, Jammu & Kashmir, India
² Department of Physics, National Institute of Technology, Hazratbal, Srinagar 190006, Jammu & Kashmir, India

^a e-mail: arfat2phy@gmail.com

Received: 20 August 2011
Revised: 1 February 2012
Accepted: 8 February 2012
Published online: 23 March 2012

Abstract

LaFe_1-xMn_xO₃ (x ≤ 0.5) polycrystals have been prepared using solid-state reaction technique and characterized by X-ray diffraction and electrical transport. XRD data suggest orthorhombic structure for both pure and Mn-doped compositions with space group Pbnma. However, unit cell dimensions are found to decrease with increase in Mn concentration. Resistivity data have been fitted with variable range hopping (VRH) model, from which different parameters like density of state at Fermi level N(E_f), hopping energy (E_h), and hopping distance (R_h) were estimated. It was observed that substitution of Mn in the series leads to the increase in conductivity of the samples with conduction being controlled by the disorder-induced localization of charge carriers.