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Schueller, A

Publications and source records attributed to Schueller, A.

3 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2011

Classical And Quantum Rainbow Scattering From Surfaces

The structure of clean and adsorbate covered surfaces as well as of ultrathin films can be investigated by grazing scattering of fast atoms. We present two recent experimental techniques which allow one to study the structure of ordered arrangements of surface atoms in detail. (1) Rainbow scattering under axial surface channeling conditions, and (2) fast atom diffraction. Our examples demonstrate the attractive features of grazing fast atom scattering as a powerful analytical tool in studies on the structure of surfaces. We will concentrate our discussion on the structure of ultrathin silica films on a Mo(112) surface and of adsorbed oxygen atoms on a Fe(110) surface.

36 MATERIALS SCIENCE↗
DOE OSTI2010

Rumpling of LiF(001) surface from fast atom diffraction

Quantum diffraction of fast atoms scattered from the topmost layer of surfaces under grazing angles of incidence can be employed for the analysis of detailed structural properties of insulator surfaces. From comparison of measured and calculated diffraction patterns we deduce the rumpling of the topmost surface layer of LiF(001) (i.e., an inward shift of Li{sup +} ions with respect to F{sup -} ions). The effect of thermal vibrations on the measurement of rumpling is accounted for by ab initio calculations of the mean-square vibrational amplitudes of surface ions. At room temperature this leads to a reduction of the apparent rumpling by 0.008 A. We then obtain a rumpling of (0.05{+-}0.04) A, which improves its accuracy achieved in previous work.

36 MATERIALS SCIENCE↗