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arXiv · 0901.3135

Charge Density Refinement of the Si (111) 7x7 Surface

J. Ciston·A. Subramanian·I. K. Robinson·L. D. Marks
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Abstract

We report an experimental refinement of the local charge density at the Si (111) 7x7 surface utilizing a combination of x-ray and high energy electron diffraction. By perturbing about a bond-centered pseudoatom model, we find experimentally that the adatoms are in an anti-bonding state with the atoms directly below. We are also able to experimentally refine a charge transfer of 0.26(4) e- from each adatom site to the underlying layers. These results are compared with a full-potential all-electron density functional DFT calculation.

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J. Ciston, A. Subramanian, I. K. Robinson, L. D. Marks. 2009-01-20. Charge Density Refinement of the Si (111) 7x7 Surface. https://doi.org/10.1103/physrevb.79.193302

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