FitIt FitIt is a free software to fit spectra using multidimensional interpolation approximation. It works under 32-bit Microsoft Windows operation systems. The main field of applications is quantitative determination of the local atomic structure parameters on the basis of fitting of X-ray absorption near edge structure (XANES). The algorithm of multidimensional interpolation of the spectrum as a function of structural parameters allows to minimize the number of time-consuming calculations required to find optimal values of the parameters.

The main program FitIt.exe has visual interface and consist of two main parts:
Tool to construct multidimensional interpolation of the spectrum as a function of a few parameters.
Subroutine for multidimensional fitting of the spectrum. It allows to find the set of parameters which corresponds to the minimal discrepancy between interpolated and experimental spectra
The program allows to use any external program for calculations of the spectrum and only small converters are needed to generate input files and read output files of any program of the user. At the moment converters for compatibility with FEFF8 and FDMNES are distributed in the FitIt package.

Also you can use any program for transformation of the geometry of your cluster. In the FitIt distributive you will find program Prot2005, which allows to perform lots of types of geometry transformations.

Using multidimensional interpolation approximation you can vary parameters by sliders and see immediately theoretical spectrum, which corresponds to this geometry. Fitting can be performed on the basis of visual comparison with experiment or using automatic procedure and quantitative criteria.

Please Cite:
G. Smolentsev, A. Soldatov “Quantitative local structure refinement from XANES: multidimensional interpolation approach” Journal of Synchrotron Radiation 2006, 13, 19-29
G. Smolentsev and A.V. Soldatov "FitIt: new software to extract structural information on the basis of XANES fitting" Comp. Matter. Science (2006)

If you would like to use FitIt please fill in form of license agreement and send it back to one of our addresses specified in this form. You can download FitIt from our site.

You can download form of license agreement in Microsoft Word or Adobe Acrobat formats.

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