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X-Ray Standing-Wave Investigations of Valence Electronic Structure
Published
Author(s)
Joseph C. Woicik, E J. Nelson, D Heskett, J Warner, L E. Berman, B A. Karlin, I A. Vartanyants, M Z. Hasan, T Kendelewicz, Z -. Shen, P Pianetta
Abstract
We have examined the valance-electron emission from Cu, Ge, GaAs, InP, and NiO single crystals under the condition of strong x-ray Bragg reflection; i.e., in the presence of the spatially modulated x-ray standing-wave interference field that is produced by the superposition of the incident and reflected x-ray beams. These crystals span the entire metallic, covalent, and ionic range of solid-state bonding. It is demonstrated that the valence-electron emission is closely coupled to the atomic cores, even for electron states close to a metallic Fermi edge. Using the bond-orbital approximation, the x-ray standing-wave structure factor for valence-electron emission is derived in terms of the bond polarities and photoionization cross sections of the atoms within the crystalline-unit cell and compared to experiment. Additionally, we demonstrate that by exploiting the spatial dependence of the electric-field intensity under Bragg condition, site-specific valance-electronic structure may be obtained. The technique is demonstrated for GaAs and NiO.
Citation
Physical Review B (Condensed Matter and Materials Physics)
Woicik, J.
, Nelson, E.
, Heskett, D.
, Warner, J.
, Berman, L.
, Karlin, B.
, Vartanyants, I.
, Hasan, M.
, Kendelewicz, T.
, Shen, Z.
and Pianetta, P.
(2001),
X-Ray Standing-Wave Investigations of Valence Electronic Structure, Physical Review B (Condensed Matter and Materials Physics)
(Accessed October 11, 2025)