title: O2 diffusion in SiO2: triplet versus singlet.
abstract: We address the diffusion of the oxygen molecule in SiO2, using first-principles spin-polarized total-energy calculations. We find that the potential energy surfaces for the singlet and triplet states are very different in certain regions, and that the O2 molecule preserves its spin-triplet ground state not only at its most stable interstitial position inside the solid but also throughout its diffusion pathway. Therefore, the singlet state is not a good approximation to describe the behavior of O2 inside SiO2, and spin-polarization effects are fundamental to understand the properties of this system.
authors.affiliation: Instituto de Física, Universidade de São Paulo, CP 66318,05315-970, São Paulo SP, Brazil.
authors.forename: W
authors.initials: W
authors.lastname: Orellana
authors.forename: A J
authors.initials: AJ
authors.lastname: da Silva
authors.forename: A
authors.initials: A
authors.lastname: Fazzio