Abstract
We computed by a modified tight binding approximation, the total electronic energy of three different hybrid polymers: H-Sio(2), CH3-SiO2 and C6H5-SiO2. We made the hypothesis that the structures of these polymers are amorphous. Computational results regarding the total electronic energy and experimental data [1] on the toughness of these three hybrid polymers were compared. A good qualitative agreement was found between computations and experiments