We study the origin of the resonant x-ray signal in manganites and generalize the resonant cross-section to the band structure framework. With {\it ab initio} LSDA and LSDA+U calculations we determine the resonant x-ray spectrum of LaMnO3. The calculated spectrum and azimuthal angle dependence at the Mn K-edge reproduce the measured data without adjustable parameters. The intensity of this signal is directly related to the orthorhombicity of the lattice. We also predict a resonant x-ray signal at the La L-edge, caused by the tilting of the MnO6 octahedra. This shows that the resonant x-ray signal in the hard x-ray regime can be understood in terms of the band structure of a material and is sensitive to the fine details of crystal structure.
@article{arxiv.cond-mat/0012084,
title = {Ab initio calculation of resonant X-ray scattering in Manganites},
author = {Patrizia Benedetti and Jeroen van den Brink and Eva Pavarini and Assunta Vigliante and Peter Wochner},
journal= {arXiv preprint arXiv:cond-mat/0012084},
year = {2009}
}
Comments
4 pages, 4 figures, accepted for publication in Phys. Rev. B