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Ab initio calculation of resonant X-ray scattering in Manganites

Patrizia Benedetti·Jeroen van den Brink·Eva Pavarini·Assunta Vigliante·Peter Wochner
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Abstract

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 LaMnO$_3$. 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 MnO$_6$ 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.

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Patrizia Benedetti, Jeroen van den Brink, Eva Pavarini, Assunta Vigliante, Peter Wochner. 2000-12-06. Ab initio calculation of resonant X-ray scattering in Manganites. https://doi.org/10.1103/physrevb.63.060408

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