Classical molecular dynamics simulations of amorphous silica surfaces

Abstract

We have adapted classical molecular dynamics to study the structural and\ndynamical properties of amorphous silica surfaces. Concerning the structure,\nthe density profile exhibits oscillations perpendicularly to the surface as\nobserved in liquid metal surfaces and the pair correlation functions as well as\nthe angle distributions show features (absent in the interior of the films)\nthat can be attributed to the presence of 2-fold rings which are perpendicular\nto the surface. From the mean-squared displacement of the non bridging oxygen\natoms we find that in the interior region they move perpendicular to the\nsurface while they move parallel to it in the surface region.\n