Strain-induced Formation of Surface Defects in Amorphous Silica: A Theoretical Prediction
Resource
Physical Review Letter.
Journal
Physical Review Letters
Pages
76104
Date Issued
2008-11
Date
2008-11
Author(s)
Abstract
We present a prediction for the formation of surface defects in a thin amorphous silica layer during relaxation of externally imposed stresses and strains, based on extensive ab initio molecular dynamics calculations. Our calculations show that the application of a biaxial compressive stress leads to the creation of edge-sharing tetrahedron and/or silanone defects at the silica surface, which turns out to facilitate strain relief with irreversible structural changes in the silica layer. We also discuss a possible correlation between the predicted formation of surface defects and the observed enhanced surface reactivity of amorphous silica under compressive strain conditions.
Type
journal article