Chirality at surfaces has become a strong focus within the surface science community. A particular motivation is the prospect of using heterogeneous catalysis over chiral solid surfaces for asymmetric synthesis, a prospect which has clear relevance to the pharmaceutical industry. Small amino acids adsorbed on Cu surfaces have emerged as important model systems for studying the interaction of chiral molecules with metal surfaces. In this article, we review the current state of knowledge of these systems, and present the results of new experimental studies of alanine overlayers on Cu{311} and {531} surfaces. Our work on Cu{311} helps us to understand the interplay between different manifestations of chirality, especially ''footprint chirality'', in the overlayers. Cu{531} is an intrinsically chiral surface orientation; our data reveal strongly enantiospecific alanine-induced restructuring of this surface. This points the way towards a promising route for obtaining strongly enantiospecific interactions with chiral adsorbates.

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The spatial and velocity distributions of desorbing product CO 2 were studied in the steady-state CO oxidation on Pt͑110͒ by cross-correlation time-of-flight techniques. The surface structure transformation was monitored by LEED in the course of the catalyzed reaction. In the active region, where the surface was highly reconstructed into the missing-row form, CO 2 desorption split into two directional lobes collimated along 25°from the surface normal in the plane including the ͓001͔ direction, indicating the CO 2 formation on inclined ͑111͒ terraces. The translational temperature was maximized at the collimation angle, reaching about 1900 K. On the other hand, CO 2 desorption sharply collimated along the surface normal at CO pressures where ͑1ϫ2͒ domains disappeared. The distribution change from an inclined desorption to a normally directed one was abrupt at the CO pressure where the half-order LEED spot already disappeared. This switching point was more sensitive than LEED towards the complete transformation from ͑1ϫ2͒ to ͑1ϫ1͒ and was then used to construct a surface phase diagram for working reaction sites in the pressure range from 1ϫ10 Ϫ7 Torr to 1ϫ10 Ϫ4 Torr of oxygen. The turnover frequency of CO 2 formation was enhanced on ͑1ϫ2͒ domains with increasing CO pressure.

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