IDENTIFICATION OF 2ND LAYER ADSORBATES - WATER AND CHLOROETHANE ON PT(111)

We show temperature-programmed desorption (TPD) evidence of (1) resolvable adsorbate structure within water bilayers and (2) a second layer peak for C2H5Cl on Pt(111) that is distinguishable both from the first layer and from thicker multilayers. The sticking probability of water was independent of the surface temperature between 55 and 150 K, but was significantly (30%) smaller at low coverage than on a multilayer-covered surface. The TPD of C2H5Cl is quite sensitive to the nature of preadsorbed water.