Jump rates for surface diffusion of large molecules from first principles
Abstract
We apply a recently developed stochastic model for the surface diffusion of large molecules to calculate jump rates for 9,10-dithioanthracene on a Cu(111) surface. The necessary input parameters for the stochastic model are calculated from first principles using density functional theory (DFT). We find that the inclusion of van der Waals corrections to the DFT energies is critical to obtain good agreement with experimental results for the adsorption geometry and energy barrier for diffusion. The predictions for jump rates in our model are in excellent agreement with measured values and show a marked improvement over transition state theory (TST). We find that the jump rate prefactor is reduced by an order of magnitude from the TST estimate due to frictional damping resulting from energy exchange with surface phonons, as well as a rotational mode of the diffusing molecule.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Apr 16, 2015
- Source ID
- 10.1063/1.4917484
Entities
People
- Hans Jürgen Kreuzer
- Patrick Shea
Organizations
- Dalhousie University
- Natural Sciences and Engineering Research Council
- Office of Naval Research