Extended Appearance-Potential Fine-Structure Analysis: Oxygen on Al(100)

M. L. den Boer; T. L. Einstein; W. T. Elam; Robert L. Park; L. D. Roelofs; G. E. Laramore

doi:10.1103/PhysRevLett.44.496

Extended Appearance-Potential Fine-Structure Analysis: Oxygen on Al(100)

M. L. den Boer, T. L. Einstein, W. T. Elam, Robert L. Park, L. D. Roelofs, and G. E. Laramore

Phys. Rev. Lett. 44, 496 – Published 18 February 1980

Abstract

To measure O-Al separation at Al(100) surfaces disordered (low-energy electron-diffraction beams extinguished) by reaction with oxygen, the extended appearance-potential fine structure was analyzed above the threshold for electron-bombardment excitation of the O $1 s$ core. Calculation shows that the outgoing electron has angular momentum $l = 0$ , allowing simple Fourier inversion of the fine structure. The separation, 1.98±0.05 Å, suggests that oxygen lies under the top layer, a result undetectable in extended-x-ray-absorption fine-structure measurements on thicker films.

Received 18 July 1979

DOI:https://doi.org/10.1103/PhysRevLett.44.496

Authors & Affiliations

M. L. den Boer^*, T. L. Einstein^†, W. T. Elam^‡, Robert L. Park, and L. D. Roelofs

Department of Physics and Astronomy, University of Maryland, College Park, Maryland 20742

G. E. Laramore

Department of Radiation Oncology, University of Washington, Seattle, Washington 98195

^*Present address: Division of Physics, National Research Council, Ottawa, Ontario K1A 0R6, Canada.
^†To whom correspondence should be addressed.
^‡Present address: Department of Physics, FM15, University of Washington, Seattle, Washington 98195.