FitIt is graphical software to fit X-ray absorption near edge structure (
XANES
X-ray absorption near edge structure (XANES), also known as near edge X-ray absorption fine structure (NEXAFS), is a type of absorption spectroscopy that indicates the features in the X-ray absorption spectra ( XAS) of condensed matter due to the ...
). It can be used to determine the values of local atomic structure parameters on the basis of minimization between theoretical and experimental spectra. It is the program for the fitting and therefore it always uses external programs, for example
FEFF8 FEFF is a software program used in x-ray absorption spectroscopy. It contains self-consistent real space multiple-scattering code for simultaneous calculations of x-ray-absorption spectra and electronic structure. Output includes extended x-ray-abs ...
or
FDMNES, for fixed geometry calculations of XANES. In order to minimize the number of such calculations, which can be very time-consuming, multidimensional interpolation algorithm is implemented into the FitIt. Such approach has allowed also to develop visual control of the fitting procedure and it is possible to vary structural parameters by sliders and immediately see the theoretical spectrum corresponding to these structural parameters.
[C. Battocchio, F. D’Acapito, G. Smolentsev, A.V. Soldatov, I. Fratoddi, G. Contini, I. Davoli, G. Polzonetti and S. Mobilio, ''XAS study of a Pt-containing rod-like organometallic polymer'']
Chem. Phys. 325, 422 (2006)
/ref>
The program is free of charge for non-commercial research and educational purposes.
PyFitIt python implementation of FitIt software was extended with additional features: Machine learning
Machine learning (ML) is a field of study in artificial intelligence concerned with the development and study of Computational statistics, statistical algorithms that can learn from data and generalise to unseen data, and thus perform Task ( ...
, automatic component analysis, direct geometry prediction and others. It uses ipywidgets to construct the portable GUI, supports different types of interpolation point generation (grid, random, IHS).
References
External links
FitIt home page
FitIt at xafs.org
{{Webarchive, url=https://web.archive.org/web/20110107095042/http://www.xafs.org/Software/FitIt , date=2011-01-07
PyFitIt home page
Physics software