“…9, we have recently employed the Poelsema and Comsa formalism to model the effects of various types of surface defects on the Cu (110) 2.1 eV RAS feature, including adsorbates such as CH 3 SH, Si, Na, and CO, and irradiation and thermally generated adatoms. 10 The simulation, which incorporates (i) changes in the associated surfaces states with temperature, and (ii) the assumption that the defects exist in a randomly distributed "lattice-gas," indicates that all the defects investigated 10 quench the 2.1 eV RAS peak with a similar effective cross section with area equivalent to a circular patch with radius R D in the range 0.5 R D 1.0 nm.…”