Self-consistent calculation of the surface electronic structure of the (1 x 2) reconstructed Au(110) surface

The stability of the Au(1 1 0)-(1 × 3) surface reconstruction in electrochemical environments

Changes in the reflection anisotropy (RAS) profile of the Au(1 1 0)-(1  ×  3)/Na2SO4 interface over 25 h are attributed to the slow accumulation of impurities on the Au(1 1 0) surface which reduce the intensity of a transition involving a surface state that makes a positive contribution to the RAS profile at 1.8 eV. The growth in the intensity of a feature that makes a negative contribution to the RAS profile at 2.6 eV and the reduction in the intensity of contributions to higher energy is attributed to shifts in the energy of the surface band structure relative to the Fermi level caused by the accumulation of impurities. There is no clear explanation of the subsequent decay of the 2.6 eV feature or the long term reduction in intensity to high energy of the RAS profile.

The reflection anisotropy spectroscopy of the Au(1 1 0) surface structures in liquid environments

The reflection anisotropy (RAS) profiles of the Au(1 1 0)-(1  ×  1), (1  ×  2) and (1  ×  3) surface structures in electrochemical environments are shown to arise mainly from surface dipole transitions directed along the principal axes of the Au(1 1 0) surface. There are weak contributions to the RAS profiles of the Au(1 1 0)-(1  ×  1) and (1  ×  3) surfaces in the region of 4.0 eV which probably arise from (1 1 1) facets that are either intrinsic to the surface structures or are associated with steps. A transition involving a surface state just above the Fermi level, E F, contributes to the RAS profiles of the (1  ×  2) and (1  ×  3) surfaces but not to the RAS profile of the (1  ×  1) surface. A strong feature at 2.5 eV in the RAS profiles of the Au(1 1 0)-(1  ×  1) and (1  ×  2) surfaces is attributed to a transition in the vicinity of the L point of the Brillouin zone between the 5d band and the [Formula: see text] band at E F. It is argued that the applied potential of  -0.6 V, which creates the Au(1 1 0)-(1  ×  3) surface, lifts E F above the [Formula: see text] band causing it to become occupied and quenching this contribution to the RAS profile.

Color view of atomic highs and lows in tunneling induced light emission

Based on a detailed experimental study of light emission stimulated with a scanning tunneling microscope, we put forward a consistent picture for the atomic-scale contrasts observed to date on noble metal surfaces. Divergent contrasts near various atomic steps and conflicting interpretations of light emission from a model atomic grating, (2 x 1) reconstructed Au(110), are accounted for. The light intensity modulation results from different spatial distributions of the local density of final states in the elastic and inelastic tunneling channels.

Reflection anisotropy spectroscopy: A new probe for the solid-liquid interface

Introducing reflection anisotropy spectroscopy (RAS) as a new probe for solid-liquid interfaces, we present results for the Au(110)/electrolyte interface which serves as a model system. We demonstrate that RAS is sensitive to surface phase transitions, step morphology, and electronic surface states. Using an empirical approach, the RA spectra are reproduced and features are identified which reflect the known character of the bias voltage driven (2x1) to (1x1) phase transition. RAS is established as an experimental technique to probe the electronic structure of solid-liquid interfaces in real time to study a wide range of interface properties.