Collective jumps of a Pt adatom on fcc-Pt (001): Nudged Elastic Band Calculation
Description: calculate the energy barrier for the self-diffusion (of a Pt-adatom) on Pt (001): The most stable adsorption site of the adatom is the hollow (h) position. Simple models of the diffusion of the adatom from h to the neighboring h site include two diffusion paths: hollow-top-hollow (hth, eg along [1-10]) or hollow-bridge-hollow (hbh, eg along [100]). A collective jump mechanism involving 2 Pt atoms diffusing along [1-10] is proposed to be the diffusion mechanism with the lowest energy barrier [1]
The calculation of the barrier heights involves the following steps:
1. calculation of the bulk a0 of Pt for the chosen functional
2. a clean Pt (001) surface, with a 2D supercell of -at minimum- (2x2) reconstruction
3. the energies of the surface including the Pt-adatom in h, b, and t position
4. a Nudged Elastic Band (NEB) calculation [2] for the proposed collective jump mechanism
steps 1-3 are straightforward, therefore only the files and the procedure for the NEB calculation are given here:
1. consider how many intermediate geometries (N) should be chosen between the initial and the final state of the jump in INCAR, this corresponds to the tag
References
- ↑ a b G.L.Kellogg and Peter J.Feibelman, Phys. Rev. Lett. 64 (26), 3143 (1990)
- ↑ a b G. Mills, H. Jonsson and G. K. Schenter, Surface Science, 324, 305 (1995); H. Jonsson, G. Mills and K. W. Jacobsen, `Nudged Elastic Band Method for Finding Minimum Energy Paths of Transitions', in `Classical and Quantum Dynamics in Condensed Phase Simulations', ed. B. J. Berne, G. Ciccotti and D. F. Coker (World Scientific, 1998)