Simulation studies for surfaces and materials strength

Abstract

The progress report for the period May 1, 1992 to October 31, 1992 is presented. During this period investigations were carried out in three areas. Binding energies and high energy binding sites were calculated for carbon atoms deposited on a (2 x 1) dimerized Si(100) surface. Structure- and energy-related properties of defects formed on relaxed diamond surfaces were investigated. Tersoff-type model functions for Si were employed to investigate the energetics of the following processes: (1) neutral monovacancy and divacancy formation and migration energies; (2) neutral bond-centered, site sharing, tetrahedral, and hexagonal self-interstitial formation and migration energies; and (3) the variation of these energies with distance from a bulk site of Frenkel defect formation and from (100) and (111) surfaces. Calculations are included in the appendices.