Identification of atoms on the Ni(110)–(2×1) O surface by scanning tunneling microscope (STM) light emission spectra

We have investigated the Ni(110)–(2×1) O surface by scanning tunneling microscope (STM) light emission spectroscopy. A mosaic of light and dark domains was seen in the STM image of the surface. The STM light emission spectra of both domains were measured to compare with that of the clean Ni(110)–(1×1) surface. We found that the dark domains are covered by the O atoms and the light domains correspond to the exposed Ni surface.