STM study of hydroxyl formation at O/Ag(110)

We report here on a low temperature scanning tunneling microscopy study of the hydroxylation of oxygen precovered Ag(110) at a crystal temperature of 250 K. For water doses comparable with the oxygen coverage, we observe complete removal of the O-Ag added rows and the formation of an OH-induced superstructure in the perpendicular (< 1 (1) over bar0 >) direction, in accord with previous results. OH sits in the channels of the unreconstructed surface, in agreement with the adsorption at threefold hollow sites proposed by K. Bange [Surf. Sci. 183, 334 (1987)]. The OH layer disorders upon localized voltage pulses. The damage extends along the < 1 (1) over bar0 > direction, suggesting a strong interaction among neighboring OH groups.