Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
7902595 | Journal of Non-Crystalline Solids | 2014 | 5 Pages |
Abstract
The network bonding, electron states and optical excitation of a larger continuous random network (CRN) model of amorphous SiO2 (a-SiO2) glass with 432 SiO2 molecules (1296 atoms) are studied by first-principles methods. A previously constructed model with perfect Si and O coordination and periodic boundary condition is first relaxed by Vienna ab initio simulation package (VASP) with high accuracy. The final model with a density 2.202 gm/c.c. and very small bond length and bond angle distortions is obtained. The calculated electronic structure and optical properties of this CRN a-SiO2 glass are in very good agreement with experimental data. This model can serve as a base-line model for silica glass for further research on models containing defects, intentional doping or under high pressure. Comparison with crystalline α-quartz (α-SiO2) yields much insight on the subtle differences between a non-crystalline solid with no long range order and its crystalline counterpart with the same short range order.
Related Topics
Physical Sciences and Engineering
Materials Science
Ceramics and Composites
Authors
Neng Li, Wai-Yim Ching,