Hyperfine Interaction Parameters in Fe_(28)Al_(72): ~(57)Fe Moessbauer Spectroscopy and Ab Initio Study

摘要

The paper discusses a theoretical model that associates the shape of the Mossbauer spectrum with the configuration of atoms in local surroundings of the Mossbauer nuclide. Using the model we analyse the Mossbauer spectra of Fe_(72)Al_(28) alloys after various heat treatments. Basing on the model calculations the hyperfine structure parameters describing an effect of an Al atom in the first and the second coordination shell of ~(57)Fe atom are evaluated. Using these parameters the values of hyperfine magnetic field and isomers shift for the atomic configurations present in stoichiometric Fe_3Al are estimated and compared with the results of ab initio calculations.