Self-Diffusion on Au(100): A Density Functional Theory Study

Institut für Theoretische Chemie, Universität Ulm, D-89081 Ulm, Germany.
ChemPhysChem (Impact Factor: 3.36). 05/2010; 11(7):1395-404. DOI: 10.1002/cphc.200900807
Source: PubMed

ABSTRACT We used density functional theory to detail new self-diffusion mechanisms on perfect and imperfect Au(100) surfaces. Herein, we report binding energies of stable intermediates and transition states lying on the potential energy surface for these systems. We report migration pathways in the presence of a variety of surface defects and along different step edges, explaining their energetics in terms of chemical bonding. Furthermore, diffusion rate constants are deduced, which are useful for both experimental verification and for implementation into large-scale kinetic Monte Carlo simulations.

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