Ab initio generation of amorphous carbon structures

Abstract

Using a new thermal process and an ab initio molecular dynamics method based on the Harris functional on original crystalline, periodically continued 64-atom diamond-like cells, we generated amorphous carbon for two different densities: 1.8 and 2.6 g/cm(3), with a 4.0-fs time step. The radial distribution functions (RDF) show the four characteristic experimental peaks. Bond angle distributions are also obtained, as well as the number of n-atom rings. The low-density sample has a larger quantity of sp(2) bonds but the high-density sample agrees better with experiment. (C) 2002 Elsevier Science B.V. All rights reserved.