GRAZING-INCIDENCE MOSSBAUER-SPECTROSCOPY - NEW METHOD FOR SURFACE-LAYERS ANALYSIS .2. THEORY OF GRAZING-INCIDENCE MOSSBAUER-SPECTRA

A general theory of grazing incidence Mossbauer spectroscopy (GIMS) spectra for an inhomogeneous layered medium is presented. The computer simulation based on this theory shows that the shape of the resonant spectrum of the reflected wave intensity, in the case of a resonant film, differs considerably from the case of a semiinfinite resonant mirror. This shape strongly depends on the thickness and the properties of the film and of the nonresonant substrate. The proposed theory of the lineshape of Mossbauer secondary radiation spectra from resonant films takes into account the influence of different types of photo- and conversion electrons on the resulting spectrum. It is shown that the fitting of grazing incidence Mossbauer spectra can be done only by means of numerical simulations.