We present extensive modeling of the amorphous silica surface, aimed at connecting its structural and chemical features. β-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.
Ceresoli, D., Bernasconi, M., Iarlori, S., Parrinello, M., Tosatti, E. (2000). Two-Membered Silicon Rings on the Dehydroxylated Surface of Silica. PHYSICAL REVIEW LETTERS, 84(17), 3887-3890 [10.1103/PhysRevLett.84.3887].
Two-Membered Silicon Rings on the Dehydroxylated Surface of Silica
BERNASCONI, MARCO;
2000
Abstract
We present extensive modeling of the amorphous silica surface, aimed at connecting its structural and chemical features. β-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.
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