Local structural aspects of the orthorhombic to pseudo-cubic phase transformation in La1-xCaxMnO3

Autor: Bozin, ES, Qiu, X, Schmidt, M, Paglia, G, Mitchell, JF, Radaelli, PG, Proffen, T, Billinge, SJL
Rok vydání: 2016
DOI: 10.1016/j.physb.2006.05.137
Popis: The local and intermediate structure of La1 - x Cax MnO3 has been studied in the orthorhombic (O) and pseudo-cubic (O′) phases, both as a function of temperature (x = 0.00), and as a function of Ca content (at 310 K). Neutron powder diffraction-based high real space resolution atomic pair distribution function (PDF) analysis shows that the Jahn Teller distortion of the MnO6 octahedra persists locally deep in the O′ phase in both cases studied, contrary to the average crystallographic view. The O to O′ structural phase transformation does have a local structural signature evidenced as a dramatic change in a PDF peak at 10.3 Å sensitive to the rotations of the MnO6 octahedra, providing further evidence that the nature of the transformation is orbital order to disorder regardless of whether the phase boundary is crossed as a function of T or x. © 2006 Elsevier B.V. All rights reserved.
Databáze: OpenAIRE