Ab initio calculations of inelastic losses and optical constants

J. J. Rehr; J. J. Kas; M. P. Prange; F. D. Vila; A. L. Ankudinov; L. W. Campbell; A. P. Sorini

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Ab initio calculations of inelastic losses and optical constants

J. J. Rehr·J. J. Kas·M. P. Prange·F. D. Vila·A. L. Ankudinov·L. W. Campbell·A. P. Sorini

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Abstract

Ab initio approaches are introduced for calculations of inelastic losses and vibrational damping in core level x-ray and electron spectroscopies. From the dielectric response function we obtain system-dependent self-energies, inelastic mean free paths, and losses due to multiple-electron excitations, while from the dynamical matrix we obtain phonon spectra and Debye-Waller factors. These developments yield various spectra and optical constants from the UV to x-ray energies in aperiodic materials, and significantly improve both the near edge and extended fine structure.

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J. J. Rehr, J. J. Kas, M. P. Prange, F. D. Vila, A. L. Ankudinov, L. W. Campbell, A. P. Sorini. 2006-01-11. Ab initio calculations of inelastic losses and optical constants. https://arxiv.org/abs/cond-mat/0601241

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