title: Two-membered silicon rings on the dehydroxylated surface of silica
abstract: We present extensive modeling of the amorphous silica surface, aimed at connecting its structural and chemical features. beta-cristobalite surfaces are initially studied to model the hydroxylated surfaces. A model reconstruction of the (111) surface is used to define a path leading to the formation of two-membered silicon rings upon dehydroxylation. Subsequently, a realistic model of the amorphous dehydroxylated (dry) surface is produced, by full ab initio annealing of an initial model generated by classical simulation. The presence of surface two-membered silicon rings emerges naturally. A calculation of IR activity yields an associated peak doublet in agreement with experimental data.
authors.affiliation: Istituto Nazionale per la Fisica della Materia and Dipartimento di Scienza dei Materiali, Universita di Milano-Bicocca, Via Cozzi 53, I-20125 Milano, Italy.
authors.initials: D
authors.lastname: Ceresoli
authors.initials: M
authors.lastname: Bernasconi
authors.initials: S
authors.lastname: Iarlori
authors.initials: M
authors.lastname: Parrinello
authors.initials: E
authors.lastname: Tosatti