The effect of Fe substitution on magnetic and transport properties of LaMnO3

Single phases of LaMn1-xFexO3 (0less than or equal toxless than or equal to0.60) have been prepared by using chemical route to study the effect of Fe substitution on magnetic and transport properties of LaMnO3. Slightly non-stoichiometric oxygen concentration is expected for these samples. Mossbauer study indicates that Fe in these compounds is in the trivalent high-spin state. The absolute value of the resistivity decreases initially at x = 0.15 and then increases rapidly with the further increase of x. The temperature dependence, p(T), is semiconducting for all the Compounds and explained well by the variable range hopping rather than the adiabatic small polaron hopping. The compounds with x less than or equal to 0.15 show ferromagnetic characters while those for x = 0.30 and greater than or equal to0.50 exhibit typical cluster glass-like and complicated glassy features, respectively. (C) 2004 Elsevier B.V. All rights reserved.