Bond-Energy and Surface-Energy Calculations in Metals

A simple technique appropriate for introductory materials science courses is outlined for the calculation of bond energies in metals from lattice energies. The approach is applied to body-centered cubic (bcc), face-centered cubic (fcc), and hexagonal-closest-packed (hcp) metals. The strength of these bonds is tabulated for a variety metals and is seen to be somewhat smaller than those typically found for the covalent bonds in molecular substances or polymers. The calculated bond energies are then combined with experimental lattice constants to illustrate the estimation of the surface energy of metals with these three crystal structures. The agreement with experiment is reasonably good, given the difficulties inherent in measuring the surface tension of metals and the considerable extrapolation required for surface-energy calculation. © 2010 The American Chemical Society and Division of Chemical Education, Inc.