Electronic-Structure Modification and the Adsorption Site of Oxygen on Alkali (Cs) Covered Surfaces Studied by Normal Exit <span class="aps-inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><mrow><msup><mrow><mi>Li</mi></mrow><mrow><mo>−</mo></mrow></msup></mrow></math></span> Ion Spectroscopy

Q. B. Lu; R. Souda; D. J. O'Connor; B. V. King

doi:10.1103/PhysRevLett.77.3236

Electronic-Structure Modification and the Adsorption Site of Oxygen on Alkali (Cs) Covered Surfaces Studied by Normal Exit ${Li}^{-}$ Ion Spectroscopy

Q. B. Lu, R. Souda, D. J. O'Connor, and B. V. King

Phys. Rev. Lett. 77, 3236 – Published 7 October 1996

Abstract

Electronic-structure change of Ni(111) surfaces with low and high Cs precoverages upon exposure to oxygen has been studied by normal exit ${Li}^{-}$ ion spectroscopy. It is shown that for low Cs coverages the ${Li}^{-}$ yield from Ni sites decreases more rapidly than from Cs; while for Cs coverages near 1 monolayer (ML), both the yields show a maximum at low O exposures, which is explained as the extension of alkali valence-electron wave functions further towards the vacuum. The results also provide the first direct evidence that oxygen atoms lie above the Cs sites for Cs coverages near 1 ML and low O exposures.

Received 18 June 1996

DOI:https://doi.org/10.1103/PhysRevLett.77.3236

Authors & Affiliations

Q. B. Lu¹, R. Souda², D. J. O'Connor¹, and B. V. King¹

¹Department of Physics, The University of Newcastle, Callaghan, New South Wales 2308, Australia
²National Institute for Research in Inorganic Materials, 1-1 Namiki, Tsukuba, Ibaraki 305, Japan