Sparse Modeling analysis of Extended X-ray Absorption Fine Structure data using two-body expansion

Fabio Iesari; Hiroyuki Setoyama; Yasuhiko Igarashi; Masato Okada; Hiroyuki Kumazoe; Kazunori Iwamitsu; Ichiro Akai; Yoshiki Seno; Toshihiro Okajima

arXiv · 2104.01805

Sparse Modeling analysis of Extended X-ray Absorption Fine Structure data using two-body expansion

Fabio Iesari·Hiroyuki Setoyama·Yasuhiko Igarashi·Masato Okada·Hiroyuki Kumazoe·Kazunori Iwamitsu·Ichiro Akai·Yoshiki Seno·Toshihiro Okajima

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Abstract

Analysis of extended X-ray absorption fine structure (EXAFS) data by the use of sparse modeling is presented. We consider the two-body term in the n-body expansion of the EXAFS signal to implement the method, together with calculations of amplitudes and phase shifts to distinguish between different back-scattering elements. Within this approach no a priori assumption about the structure is used, other than the elements present inside the material. We apply the method to the experimental EXAFS signal of metals and oxides, for which we were able to extract the radial distribution function peak positions, and the Debye-Waller factor for first neighbors.

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Fabio Iesari, Hiroyuki Setoyama, Yasuhiko Igarashi, Masato Okada, Hiroyuki Kumazoe, Kazunori Iwamitsu, Ichiro Akai, Yoshiki Seno, Toshihiro Okajima. 2021-04-05. Sparse Modeling analysis of Extended X-ray Absorption Fine Structure data using two-body expansion. https://arxiv.org/abs/2104.01805

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