From the classical point of view the structure of the amorphous materials might be done by the Radial Distribution Function and Pair Distribution Function analyses. In fact the presence of the short-range order in the amorphouse state points to the possibilities of applying the "semi" crystalline model of structure with the crystalline size up to ~10-20 nm. Than it is possible to use the Rietveld method to refining the "hypothetical unit cell" of the amorphous meterial. In this paper there are tested different models of unit cells characteristic for Fe-B-X alloys. The refinement results are compared to the RDF results (coordination radii and numbers). Thanks to applying the Rietveld method to describing the diffusion scattering there is possible to calculate parameters characterizing the searching material as crystallite size, lattice strain, changes of order in material, etc.