A Comparative Study of Oxygen Vacancy Migration Pathways in Crystalline Polymorphs of Silica
نویسندگان
چکیده
The migration pathway and energy of an oxygen vacancy were calculated in quartz, stishovite and cristobolite using an empirical potential. For comparison the minimum energy pathway in quartz was calculated using density functional theory. The differences between the two methods show that although the energies of both approaches are similar, the pathways go through different intermediate states and, hence, the mechanisms of diffusion would appear to be different.
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