We report simulations of a theoretical model describing the formation of holographic diffraction gratings in multicomponent materials. The concentration of the chemical species in the initial mixture plays a fundamental role in determining the final features of the realized sample; our investigation is devoted to determine the best initial mixture realizing good holographic gratings. Along with the model, that is valid for any initial the multicomponent mixture, we report a complete characterization of the numerical solution of the model for two well known cases: H-PDLC and POLICRYPS grating. Obtained results are in good agreement with experimental observation, showing that our model represent a necessary reference for fabrication and the characterization of holographic diffraction gratings in multicomponent materials.