Open AccessThe construction of a photoabsorption spectrum using the FEFF 9 package: a detailed procedure
Author(s) -
Gildardo Rivas Valles
Publication year - 2021
Publication title -
acta universitaria
Language(s) - English
Resource type - Journals
eISSN - 2007-9621
pISSN - 0188-6266
DOI - 10.15174/au.2021.3214
Subject(s) - spectrum (functional analysis) , spectroscopy , absorption spectroscopy , materials science , electromagnetic spectrum , atomic physics , absorption (acoustics) , computational physics , physics , optics , quantum mechanics
A procedure to obtain a photoabsorption spectrum assembled from first-principles calculations made with the FEFF 9 spectroscopy package is presented. The calculation consists of obtaining the absorption cross-section of electromagnetic radiation for each electronic shell of an atom inside a solid; the total value is obtained by the sum of the contributions of all shells. A complete spectrum is shown for metallic copper as an example, covering values from ultraviolet above 10 eV (approximately) to x-rays. The spectrum is compared selectively with values from frequently used tables and with results taken from the literature. The advantages of the FEFF 9 package and its limitations are compared; as well, the preliminary nature of the presented results and the need for convergence studies are highlighted, suggesting future work.