Degree Type

Dissertation

Date of Award

1990

Degree Name

Doctor of Philosophy

Department

Chemistry

Abstract

The energetics and structures of clean and adsorbate covered surfaces are investigated in this dissertation. First, the formalism, within the Corrected Effective Medium (CEM) method, for calculating the surface energy of a clean surface is derived. The surface energies for many different metals and their low index surfaces are presented. The minimization of the surface energy is then used to predict the multilayer relaxation of the Al(111), (100), (110), Ni(100), (110) and Fe(100) surfaces. The driving forces behind surface relaxation is then examined within the CEM method;Extensions of the surface CEM formalism to calculate the binding energies of ordered adsorbates on metals surfaces are also derived. The minimization of the binding energy allowed determination of the binding heights, sites and the extent of induced multilayer relaxation for H and N atoms on the Fe(110), (100) and W(110) surfaces;The last topic deals with the dynamics of the epitaxial growth of metals on metal surfaces. The CEM method was first modified by making approximations to enable faster evaluations of the potential and its corresponding forces for molecular dynamics simulations. The goal of these simulations was to identify the important steps in the formation of equilibrium epitaxial structures. Molecular dynamics simulation results are presented for the Rh on Ag(100) and Au on Cu(100) systems. Static calculations for Au on Ag(110) system are also presented.

DOI

https://doi.org/10.31274/rtd-180813-9407

Publisher

Digital Repository @ Iowa State University, http://lib.dr.iastate.edu/

Copyright Owner

Todd Joseph Raeker

Language

en

Proquest ID

AAI9110554

File Format

application/pdf

File Size

182 pages

Share

COinS