The onset of disorder in Al(110) surfaces below the melting point

Molecular dynamics simulations of the disordering of Al(110) surfaces below the melting point are presented. Effective medium theory has been used to calculate the inter-atomic many-body interactions of the metallic system. The origin of the anisotropy of the disordering with respect to the direction along the surface deduced from LEED experiments is suggested to be mainly a consequence of the g² dependence of the Debye-Waller factor even for non-harmonic interactions. Further evidence is presented showing that the disordering of the first layers coincides with the onset of surface vacancy formation.