Mössbauer study of the relationship between magnetic properties and Jahn–Teller distortion in La1–xBax(Mn,Fe)O3 perovskites

Abstract

AbstractThe local structural distortion and its effect on the magnetic and magnetotransport properties of the Fe‐doped La1–xBaxMnO3 (0.00 ≤ x ≤ 0.35) compounds were investigated by means of X‐ray diffraction, Mössbauer spectroscopy, and magnetization measurements. The Mössbauer spectra show clear evidence of the local structural distortion of the Mn(Fe)O6 octahedron on the basis of non‐zero nuclear quadrupole interactions for high‐spin Fe3+ ions. It was found that the local structural distortion decreases significantly with the introduction of a few per cent of Ba, reaches a minimum around x = 0.13, and then increases slightly on further increasing the Ba concentration. The Ba‐concentration dependence of the Jahn–Teller coupling strength estimated from the Mössbauer results was found to be consistent with the magnetic properties. Consequently, the connection between this local structural distortion and the colossal magnetoresistive behavior of this family of materials can be well explained. (© 2005 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)