In situ second harmonic generation studies of underpotential deposition of Cu on Au(111) and Ag on Pt(111) were presented. Fast dynamics during repetitive step voltage application were studied in a millisecond range. Isotropic and onefold second harmonic generation terms transients, which were the measures of surface charge and surface reconstruction, respectively, revealed different time constants. A stable fast surface reconstruction was observed during Ag underpotential deposition on Pt(111) surface with a time constant of 35ms. Second harmonic generation measurements were consistent with atomic force microscopic images showing terrace-pattern formation during repetitive underpotential deposition on Pt surface. A √3 x √3 surface reconstruction at Cu on Au(111) surface was shown to be frozen within a millisecond range, and a → 1 x 1 phase transition did not take place.

Dynamics of Surface Reconstruction and Electrodeposition Studied in situ by Second Harmonic Generation. E.D.Mishina, N.Ohta, Q.K.Yu, S.Nakabayashi: Surface Science, 2001, 494[1], L748-54