Local scale ordering in LaMnO3 under pressure: X-ray absorption study

A.Y. RAMOS; H.C.N. TOLENTINO; M.M. SOUZA NETO; A. CANEIRO; Y. YOLY; J.P. ITIÉ; A.M. FLANK; P. LAGARDE

Journal of Physics. conference Series

IOP Publishing

Año: 2009 vol. 190 p. 1 - 6

1742-6588

The present study aims, by using X-ray Absorption Spectroscopy, to describe thelocal process towards the pressure-induced abrupt changes in the resistivity in the Jahn-Tellerdistorted LaMnO3 doped compounds. Local environment of manganese atoms under pressureup to 37 GPa has been studied by X-ray absorption spectroscopy. We identify successive stepstowards the pressure-induced abrupt changes in the resistivity. These steps are associatedto local processes such as the opening of the inter-octahedra tilt angles and the averagesymmetrization of the Mn local environment. All modifications present a hysteretic behaviorwhen the pressure is released, pointing to the coexistence of MnO6 distorted and undistortedunits.