FLUCTUATION KINETICS OF AN ISOLATED AG(110) STEP

We study the equilibrium thermal fluctuations of a Ag(110) step at roo m temperature with scanning tunneling microscopy. By employing a Lange vin analysis, step fluctuations are shown to be determined by adatoms exchanging between terraces and steps, and the room-temperature detach ment rate from steps is estimated to be 3 atoms/s per step site. The m ass transport mechanism at steps and the efficiency of the step as an adatom source bear directly on the kinetics of surface reactions that involve the participation of substrate atoms. We will briefly discuss the O/Ag(110) system as an example.