| Abstract
| - The adsorption of l-lysine on a Cu(110) surface has been investigated under UHV conditions from the sublimationof a crystalline phase. The adsorption was characterized by Fourier transform reflection absorption infrared spectroscopy(FT-RAIRS) during exposure and Auger electron spectroscopy (AES). At room temperature, the lysine molecules'adsorption geometry varies as a function of the exposure. At low coverage, the molecules are adsorbed via the oxygenatoms of the deprotonated carboxylate group and the nitrogen atom of the amino group. At high coverage, close tothe monolayer, the molecules reorient to be anchored to the surface via one oxygen of a sideways-tilted carboxylatemoiety. This first step is followed by the growth of multilayers of nonoriented molecules. In contrast, adsorption onan oxygen-modified copper surface leads to a rather disordered layer. The results are compared with the adsorptioncarried out on a polycrystalline copper surface after immersion in solutions of lysine at various pH values. Theadsorption was monitored by polarization modulation infrared spectroscopy (PM-IRRAS). The chemistry of theadsorbed molecules is function of the starting chemical form of the lysine molecules imposed by the pH of the solution.The combination of the two techniques and various sets of adsorption conditions will give important insight into theadsorption of biomolecules on metal surfaces and the influence of water and surface oxygen.
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