Network transformation processes during oxidation of silicon

Using density functional calculations in the generalized gradient approxima tion, the energetics of competing atomic processes occuring during the oxid ation of silicon are evaluated. Simple molecular systems are used to model the breaking of Si-Si and Si-O bonds in the oxide. These calculations sugge st that the breaking of Si-Si bonds and the formation of threefold coordina ted O atoms are the most favourable transformation pathways of the bonding network of the oxide, in accord with the atomic processes observed during a recent first-principle molecular dynamics simulation.