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arXiv · 0912.0792

Effect of vibrations on the pre-edge features of x-ray absorption spectra

Christian Brouder·Delphine Cabaret·Amélie Juhin·Philippe Sainctavit
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Abstract

The influence of atomic vibrations on x-ray absorption near edge structure (XANES) is calculated by assuming that vibrational energies are small with respect to the instrumental resolution. The resulting expression shows that, at the K-edge, vibrations enable electric dipole transitions to 3s and 3d final states. The theory is applied to the K-edge of Al in Al2O3 corundum and of Ti in TiO2 rutile and compared with experiment. At the Al K-edge, sizeable transitions towards 3s final states are obtained, leading to a clear improvement of the agreement with experimental spectra. At the Ti K-edge, electric dipole transitions towards 3d final states explain the temperature dependence of the pre-edge features.

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Christian Brouder, Delphine Cabaret, Amélie Juhin, Philippe Sainctavit. 2009-12-04. Effect of vibrations on the pre-edge features of x-ray absorption spectra. https://doi.org/10.1103/physrevb.81.115125

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