Spatial and Temporal Dynamics of Individual Step Merging Events on Ni(977) Measured by Scanning Tunneling Microscopy
| Autor: | Steven J. Sibener, T. P. Pearl |
|---|---|
| Rok vydání: | 2001 |
| Předmět: |
Scattering
Chemistry Analytical chemistry chemistry.chemical_element Molecular physics Oxygen Surfaces Coatings and Films law.invention Nickel Chemisorption law Materials Chemistry Limiting oxygen concentration Physical and Theoretical Chemistry Scanning tunneling microscope Vicinal Surface reconstruction |
| Zdroj: | The Journal of Physical Chemistry B. 105:6300-6306 |
| ISSN: | 1520-5207 1520-6106 |
| DOI: | 10.1021/jp011165c |
| Popis: | Step dynamics induced by the chemisorption of oxygen on Ni(977) at low coverages and elevated temperatures have been studied using scanning tunneling microscopy (STM). Previous experiments using both local probe and scattering techniques have assessed the surface reconstruction behavior and structural transformations for this vicinal system. At temperatures above 390 K, the surface is capable of undergoing step doubling or merging if exposed to small amounts of oxygen. These double steps exist up to 565 K, where step-adsorbed oxygen dissolves into the nickel lattice destabilizing this morphology. Real-time STM measurements have been made on the behavior of individual merging events as a function of local step density, and hence local oxygen concentration at step edges, at 465 K. Results indicate that there is an optimal oxygen coverage, corresponding to complete titration of the single step density, that enables fast step merging to occur. An areal sweep rate of ∼60 A2 s-1 was found for step doubling unde... |
| Databáze: | OpenAIRE |
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