Both silica (SiO2 ) and water are ubiquitous in our environment and our technologies. They come together in two important processes: the oxidation of silicon by steam, which is a process step in integrated circuit fabrication, and the hydrolytic weakening of quartz, which helps us understand plate tectonics. In the former process water molecules must diffuse through an amorphous silica layer and in the latter they must diffuse through quartz to reach dislocations and bubbles to promote plasticity.
We have taken a molecular fragment of SiO2 based on an a quartz c channel, with a hydrogenated external surface and with an internal water molecule. Ab initio, local density, total energy calculations, relaxing the water molecule and the atoms lining the channel, have been applied to discover the insertion energy of water in quartz. In addition, this quantity has been examined in a c axis dislocation core, in order to evaluate the ease of pipe diffusion in the case of hydrolytic weakening and to better simulate amorphous SiO2 in the case of silicon oxidation.