How Atomic Steps Modify Diffusion and Inter-adsorbate Forces: Empirical Evidence From Hopping Dynamics in Na/Cu(115)
The Journal of Physical Chemistry Letters
MetadataShow full item record
Godsi, O., Corem, G., Kravchuk, T., Bertram, C., Morgenstern, K., Hedgeland, H., Jardine, A., et al. (2015). How Atomic Steps Modify Diffusion and Inter-adsorbate Forces: Empirical Evidence From Hopping Dynamics in Na/Cu(115). The Journal of Physical Chemistry Letters, 6 4165-4170. https://doi.org/10.1021/acs.jpclett.5b01939
We followed the collective atomic-scale motion of Na atoms on a vicinal Cu(115) surface within a time scale of pico- to nanoseconds using helium spin echo spectroscopy. The well-defined stepped structure of Cu(115) allows us to study the effect that atomic steps have on the adsorption properties, the rate for motion parallel and perpendicular to the step edge, and the interaction between the Na atoms. With the support of a molecular dynamics simulation we show that the Na atoms perform strongly anisotropic 1D hopping motion parallel to the step edges. Furthermore, we observe that the spatial and temporal correlations between the Na atoms that lead to collective motion are also anisotropic, suggesting the steps efficiently screen the lateral interaction between Na atoms residing on different terraces.
This work was supported by the German-Israeli Foundation for Scientific Research and Development, the Israeli Science Foundation (Grant No. 2011185), the German Science Foundation (DFG) through contract MO 960/18-1, the Cluster of Excellence RESOLV (EXC 1069), and the European Research Council under the European Union’s seventh framework program (FP/2007-2013)/ERC Grant 307267.
External DOI: https://doi.org/10.1021/acs.jpclett.5b01939
This record's URL: https://www.repository.cam.ac.uk/handle/1810/252402