SURFACE STRUCTURAL TRANSITION OF ADSORPTION OF OXYGEN ON AG(100)

High resolution electron energy loss spectroscopy (HREELS) and low energy electron diffraction (LEED) were used to study the oxygen adsorption on Ag(100). An ordered c(2 × 2) superstructure occurs after low temperature adsorption, in which the stretching mode at 37 meV was observed. The energy loss at 30 meV is attributed to the ordered p(1 × 1) structure after the adsorption at room temperature. The structure transition from the c(2 × 2) to the p(1 × 1) has been observed when heating the adsorbed surface from low temperature to room temperature. Cooling of the adsorbed surface at room temperature down to 180 K results in the surface transition from the p(1 × 1) structure to the coexistence of the p(1 × 1) and c(2 × 2) structures. © 1990.