This web-page is the home for a simulation-based approach for the analysis of extended X-ray absorption fine structure (EXAFS) spectra. The method is based on reverse Monte Carlo modeling of the material's 3D structure. It is developed to probe the local structural and thermal disorder in crystalline and nanocrystalline materials. We believe that the proposed method improves the accuracy of currently available approaches for EXAFS analysis, especially in the case of strongly distorted local environment, and for the analysis of the contributions of distant coordination shells. The method is implemented in freely available EvAX code (see Downloads section).
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Distant shells, Multiple-scattering To benefit from the structural information, hidden in the contribution of multiple-scattering effects and of distant coordination shells, EvAX code provides great flexibility for treating all important scattering paths with user-specified precision.
Evolutionary algorithm for optimization The optimization process that employs the power of evolutionary algorithm allows much more efficient exploration of the possible configuration space and makes feasible advanced analysis of complex compounds with low symmetry even with only decent computational resources available.
Wavelet transform for spectra comparison The representation of EXAFS spectra in k- and R-spaces simultaneously using Morlet wavelet transform allows one to obtain more information from the same data and to have better control over the difference between the experimental and calculated EXAFS spectra.
Analysis of EXAFS at several edges EvAX code allows one to construct an unambiguous single structure model, consistent with EXAFS data, acquired at several absorption edges.