Résumé
Bridged silsesquioxane nanomaterials exhibit original mechanical properties thanks to the association of non-covalent and covalent interactions. Thanks to in situ high pressure spectroscopic studies, achieved in diamond anvil cells, the mechanical behavior of these materials was followed as a function of pressure. Vibrational studies coupled to ab-initio simulations show that mechanical constrains are absorbed by the modulation of H bond interactions. We thus show that the rigidity yielded by the inorganic polymerization is counterbalanced by the presence of the intermolecular H bond network. In a large range of pressures, these hybrid materials have a reversible behavior, and thus behave as molecular springs. In a second time, we demonstrate that the pressure behavior of these molecular spring is sensitive to the conformation of H bonds (cyclic versus linear) and to the constraints imposed the covalent inorganic network.