Figures from "Chlorine-Induced Restructuring of Ag(111) Films Observed by Scanning Tunneling Microscopy", by E.R. Frank and R.J. Hamers, Journal of Catalysis, vol. 172, pp. 406-413 (1997)

© 1997 Academic Press

Note: All the figures shown here have been published and copyrighted. If you use or reproduce any of these figures in any way, you must indicate the original source of the image. For electronic or paper publication, you must receive written permission from Robert Hamers and the Academic Press.

Figure 1

Real-time monitoring of Cl2 exposure on Ag(111) at room temperature. Dose started after (A). Time between images is 6 min. Steps are seen to initially roughen then bunch into two distinct periodicities. Dosing pressure, 2 x 10-9 Torr. Image size, 4000 x 4000 Å.

Figure 2

Higher resolution image of the two step bunches. Steps running along the "A" direction have a separation of 6 lattice constants, while those running along the "B" direction have a separation of 15 lattice constants. Image size, 1000 x 1000 Å.

Figure 3

Auger spectrum of the room temperature dosed Ag(111) film. Cl/Ag peak height ratio is 0.30. Total exposure of 0.32 L. Saturation (ØCl=0.52) Cl/Ag height ratio is 0.41; absolute ØCl=0.38 for the facetted surface.

Figure 4

Height profile scans across a room temperature Cl-exposed Ag(111) film and the same film annealed to 220°C. The height of the spacing between the microfacets increases with annealing.

Figure 5

STM image of room temperature Cl dosed Ag(111) film annealed to 530°C. The reconstruction induced by the Cl adsorption is lifted and the surface resembles a clean annealed Ag(111) film. Image size, 800 x 800 Å.

Figure 6

Step distance probability distribution function for clean and Cl-exposed Ag(111). The function represents the probability that a reactive molecule will diffuse a given distance before encountering a step. While the absolute number of steps remains constant, the spatial distribution of steps along the surface changes dramatically, all surface sites being within 350 Å of a step edge in the undosed sample, while a significant number of surface sites are greater than 350 Å from steps on the chlorine-dosed film.

Last updated February 2, 1998