The motivation of this work is to apply a new model, which we had called the Global Reactions Model (GRM), for the theoretical study of the optical and electronics properties of Silicon Rich Oxides (SRO) structures regardless of the technique used to fabricate such structures. Recently we published the Global Reactions Model (GRM) to describe a set of chemical reactions that could hypothetically occur during the process of obtaining silicon rich oxide (SRO) films, notwithstanding of the technique used to grow such films. Particularly, chemical reactions that occur during the process of growing of SRO films by Low Pressure Chemical Vapor Deposition (LPCVD) and Hot Filament Chemical Vapor Deposition (HFCVD) techniques were emphasized in these models. We suggest and evaluate either some types of molecules or resulting nanostructures and we have predicted theoretically, by applying the density functional theory (DFT), the contribution that they may have to the phenomenon of luminescence. We calculated the luminescent spectra of the as grown and the annealed structures. In this work we focused in siloxanes species presumably found in SRO.