It was recalled that the hydrolytic weakening of quartz required the diffusion of H2O to dislocation cores, while the oxidation of Si required the diffusion of O and/or H2O through amorphous silica. Perfect α-quartz channels and larger dislocation channels were used to model diffusion in α-quartz and amorphous SiO2 by using a classical interatomic potential for SiO2. The results showed that H2O and O molecules were heavily compressed in perfect channels, but much less so in the dislocation channels. The diffusion of these molecules through enlarged channels involved much lower activation energies, and therefore such channels were preferred to the perfect ones.

M.I.Heggie, R.Jones, C.D.Latham, S.C.P.Maynard, P.Tole: Philosophical Magazine B, 1992, 65[3], 463-71. See also: Philosophical Magazine Letters, 1992, 65[3], 155-8