Thermal roughening of an SOS-model with elastic interaction

We analyze the effects of a long-ranged step-step interaction on thermal roughening within the framework of a solid-on-solid model of a crystal surface by means of Monte Carlo simulation. A repulsive step-step interaction is modeled by elastic dipoles located on sites adjacent to the steps. In order to reduce the computational effort involved in calculating interaction energy based on long-ranged potentials, we employ a multi-grid scheme. As a result of the long-range character of the step interaction, the roughening temperature increases drastically compared to a system with short-range cutoff as a consequence of anti-correlations between surface defects

First-principles step- and kink-formation energies on Cu(111)

In rough agreement with experimental values derived from Cu island shapes vs. temperature, ab-initio calculations yield formation energies of 0.27 and 0.26 eV/ step-edge-atom for (100)- and (111)-micro facet steps on Cu(lll), and 0.09 and 0.12 eV per kink in those steps. Comparison to ab-initio results for Al and Pt shows that as a rule, the average formation energy of straight steps on a close-packed metal surface equals -7% of the metal's cohesive energy