Open AccessTemperature/magnetization‐induced distortions in the local structure of substituted LaMnO 3
Author(s) -
Bridges F.,
Cao D.,
Anderson M.,
Booth C.,
Neumeier J. J.,
Snyder J.
Publication year - 1999
Publication title -
journal of synchrotron radiation
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.172
H-Index - 99
ISSN - 1600-5775
DOI - 10.1107/s0909049598016008
Subject(s) - magnetization , materials science , condensed matter physics , physics , magnetic field , quantum mechanics
Much of the work carried out on the Colossal Magnetoresistive (CMR) materials has been interpreted using the double exchange (DE) model which assumes Mn +a and Mn +4 sites exist. In addition, to explain the large MR in films, it has recently been suggested that local distortions in the form of polarons, must also be present above the ferromagnetic transition temperature Tc; such distortions have now been observed. We present XAFS data which illustrate the magnitude of these distortions and show that the change in the Mn-O distortions correlates well with the magnetization. However the absorption edge is sharp and shows no structure indicative of two valence states, Mn +3 and Mn +4, in either the polaron regime or in the charge-ordered material.